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kernel/signal.c
94.9 KB
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/* * linux/kernel/signal.c * * Copyright (C) 1991, 1992 Linus Torvalds * * 1997-11-02 Modified for POSIX.1b signals by Richard Henderson * * 2003-06-02 Jim Houston - Concurrent Computer Corp. * Changes to use preallocated sigqueue structures * to allow signals to be sent reliably. */ |
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#include <linux/slab.h> |
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#include <linux/export.h> |
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#include <linux/init.h> #include <linux/sched.h> #include <linux/fs.h> #include <linux/tty.h> #include <linux/binfmts.h> |
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#include <linux/coredump.h> |
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#include <linux/security.h> #include <linux/syscalls.h> #include <linux/ptrace.h> |
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#include <linux/signal.h> |
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#include <linux/signalfd.h> |
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#include <linux/ratelimit.h> |
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#include <linux/tracehook.h> |
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#include <linux/capability.h> |
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#include <linux/freezer.h> |
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#include <linux/pid_namespace.h> #include <linux/nsproxy.h> |
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#include <linux/user_namespace.h> |
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#include <linux/uprobes.h> |
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#include <linux/compat.h> |
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#define CREATE_TRACE_POINTS #include <trace/events/signal.h> |
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|
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#include <asm/param.h> #include <asm/uaccess.h> #include <asm/unistd.h> #include <asm/siginfo.h> |
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#include <asm/cacheflush.h> |
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#include "audit.h" /* audit_signal_info() */ |
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/* * SLAB caches for signal bits. */ |
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static struct kmem_cache *sigqueue_cachep; |
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|
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int print_fatal_signals __read_mostly; |
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static void __user *sig_handler(struct task_struct *t, int sig) |
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{ |
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return t->sighand->action[sig - 1].sa.sa_handler; } |
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|
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static int sig_handler_ignored(void __user *handler, int sig) { |
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/* Is it explicitly or implicitly ignored? */ |
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return handler == SIG_IGN || (handler == SIG_DFL && sig_kernel_ignore(sig)); } |
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|
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static int sig_task_ignored(struct task_struct *t, int sig, bool force) |
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{ |
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void __user *handler; |
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|
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handler = sig_handler(t, sig); if (unlikely(t->signal->flags & SIGNAL_UNKILLABLE) && |
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handler == SIG_DFL && !force) |
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return 1; return sig_handler_ignored(handler, sig); } |
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static int sig_ignored(struct task_struct *t, int sig, bool force) |
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{ |
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/* * Blocked signals are never ignored, since the * signal handler may change by the time it is * unblocked. */ |
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if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig)) |
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return 0; |
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if (!sig_task_ignored(t, sig, force)) |
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return 0; /* * Tracers may want to know about even ignored signals. */ |
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return !t->ptrace; |
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} /* * Re-calculate pending state from the set of locally pending * signals, globally pending signals, and blocked signals. */ static inline int has_pending_signals(sigset_t *signal, sigset_t *blocked) { unsigned long ready; long i; switch (_NSIG_WORDS) { default: for (i = _NSIG_WORDS, ready = 0; --i >= 0 ;) ready |= signal->sig[i] &~ blocked->sig[i]; break; case 4: ready = signal->sig[3] &~ blocked->sig[3]; ready |= signal->sig[2] &~ blocked->sig[2]; ready |= signal->sig[1] &~ blocked->sig[1]; ready |= signal->sig[0] &~ blocked->sig[0]; break; case 2: ready = signal->sig[1] &~ blocked->sig[1]; ready |= signal->sig[0] &~ blocked->sig[0]; break; case 1: ready = signal->sig[0] &~ blocked->sig[0]; } return ready != 0; } #define PENDING(p,b) has_pending_signals(&(p)->signal, (b)) |
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static int recalc_sigpending_tsk(struct task_struct *t) |
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{ |
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if ((t->jobctl & JOBCTL_PENDING_MASK) || |
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PENDING(&t->pending, &t->blocked) || |
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PENDING(&t->signal->shared_pending, &t->blocked)) { |
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set_tsk_thread_flag(t, TIF_SIGPENDING); |
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return 1; } |
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/* * We must never clear the flag in another thread, or in current * when it's possible the current syscall is returning -ERESTART*. * So we don't clear it here, and only callers who know they should do. */ |
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return 0; } /* * After recalculating TIF_SIGPENDING, we need to make sure the task wakes up. * This is superfluous when called on current, the wakeup is a harmless no-op. */ void recalc_sigpending_and_wake(struct task_struct *t) { if (recalc_sigpending_tsk(t)) signal_wake_up(t, 0); |
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} void recalc_sigpending(void) { |
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if (!recalc_sigpending_tsk(current) && !freezing(current)) |
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clear_thread_flag(TIF_SIGPENDING); |
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} /* Given the mask, find the first available signal that should be serviced. */ |
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#define SYNCHRONOUS_MASK \ (sigmask(SIGSEGV) | sigmask(SIGBUS) | sigmask(SIGILL) | \ |
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sigmask(SIGTRAP) | sigmask(SIGFPE) | sigmask(SIGSYS)) |
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|
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int next_signal(struct sigpending *pending, sigset_t *mask) |
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{ unsigned long i, *s, *m, x; int sig = 0; |
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|
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s = pending->signal.sig; m = mask->sig; |
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/* * Handle the first word specially: it contains the * synchronous signals that need to be dequeued first. */ x = *s &~ *m; if (x) { if (x & SYNCHRONOUS_MASK) x &= SYNCHRONOUS_MASK; sig = ffz(~x) + 1; return sig; } |
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switch (_NSIG_WORDS) { default: |
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for (i = 1; i < _NSIG_WORDS; ++i) { x = *++s &~ *++m; if (!x) continue; sig = ffz(~x) + i*_NSIG_BPW + 1; break; } |
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break; |
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case 2: x = s[1] &~ m[1]; if (!x) |
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break; |
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sig = ffz(~x) + _NSIG_BPW + 1; |
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break; |
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case 1: /* Nothing to do */ |
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break; } |
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|
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return sig; } |
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static inline void print_dropped_signal(int sig) { static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10); if (!print_fatal_signals) return; if (!__ratelimit(&ratelimit_state)) return; printk(KERN_INFO "%s/%d: reached RLIMIT_SIGPENDING, dropped signal %d ", current->comm, current->pid, sig); } |
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/** |
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* task_set_jobctl_pending - set jobctl pending bits |
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* @task: target task |
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* @mask: pending bits to set |
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* |
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* Clear @mask from @task->jobctl. @mask must be subset of * %JOBCTL_PENDING_MASK | %JOBCTL_STOP_CONSUME | %JOBCTL_STOP_SIGMASK | * %JOBCTL_TRAPPING. If stop signo is being set, the existing signo is * cleared. If @task is already being killed or exiting, this function * becomes noop. * * CONTEXT: * Must be called with @task->sighand->siglock held. * * RETURNS: * %true if @mask is set, %false if made noop because @task was dying. */ bool task_set_jobctl_pending(struct task_struct *task, unsigned int mask) { BUG_ON(mask & ~(JOBCTL_PENDING_MASK | JOBCTL_STOP_CONSUME | JOBCTL_STOP_SIGMASK | JOBCTL_TRAPPING)); BUG_ON((mask & JOBCTL_TRAPPING) && !(mask & JOBCTL_PENDING_MASK)); if (unlikely(fatal_signal_pending(task) || (task->flags & PF_EXITING))) return false; if (mask & JOBCTL_STOP_SIGMASK) task->jobctl &= ~JOBCTL_STOP_SIGMASK; task->jobctl |= mask; return true; } /** |
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* task_clear_jobctl_trapping - clear jobctl trapping bit |
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* @task: target task * |
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* If JOBCTL_TRAPPING is set, a ptracer is waiting for us to enter TRACED. * Clear it and wake up the ptracer. Note that we don't need any further * locking. @task->siglock guarantees that @task->parent points to the * ptracer. |
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* * CONTEXT: * Must be called with @task->sighand->siglock held. */ |
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void task_clear_jobctl_trapping(struct task_struct *task) |
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{ |
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if (unlikely(task->jobctl & JOBCTL_TRAPPING)) { task->jobctl &= ~JOBCTL_TRAPPING; |
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wake_up_bit(&task->jobctl, JOBCTL_TRAPPING_BIT); |
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} } /** |
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* task_clear_jobctl_pending - clear jobctl pending bits |
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* @task: target task |
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* @mask: pending bits to clear |
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* |
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* Clear @mask from @task->jobctl. @mask must be subset of * %JOBCTL_PENDING_MASK. If %JOBCTL_STOP_PENDING is being cleared, other * STOP bits are cleared together. |
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* |
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* If clearing of @mask leaves no stop or trap pending, this function calls * task_clear_jobctl_trapping(). |
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* * CONTEXT: * Must be called with @task->sighand->siglock held. */ |
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void task_clear_jobctl_pending(struct task_struct *task, unsigned int mask) |
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{ |
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BUG_ON(mask & ~JOBCTL_PENDING_MASK); if (mask & JOBCTL_STOP_PENDING) mask |= JOBCTL_STOP_CONSUME | JOBCTL_STOP_DEQUEUED; task->jobctl &= ~mask; |
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if (!(task->jobctl & JOBCTL_PENDING_MASK)) task_clear_jobctl_trapping(task); |
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} /** * task_participate_group_stop - participate in a group stop * @task: task participating in a group stop * |
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* @task has %JOBCTL_STOP_PENDING set and is participating in a group stop. |
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* Group stop states are cleared and the group stop count is consumed if |
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* %JOBCTL_STOP_CONSUME was set. If the consumption completes the group |
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* stop, the appropriate %SIGNAL_* flags are set. |
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* * CONTEXT: * Must be called with @task->sighand->siglock held. |
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* * RETURNS: * %true if group stop completion should be notified to the parent, %false * otherwise. |
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*/ static bool task_participate_group_stop(struct task_struct *task) { struct signal_struct *sig = task->signal; |
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bool consume = task->jobctl & JOBCTL_STOP_CONSUME; |
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|
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WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING)); |
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|
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task_clear_jobctl_pending(task, JOBCTL_STOP_PENDING); |
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if (!consume) return false; if (!WARN_ON_ONCE(sig->group_stop_count == 0)) sig->group_stop_count--; |
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/* * Tell the caller to notify completion iff we are entering into a * fresh group stop. Read comment in do_signal_stop() for details. */ if (!sig->group_stop_count && !(sig->flags & SIGNAL_STOP_STOPPED)) { |
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sig->flags = SIGNAL_STOP_STOPPED; return true; } return false; } |
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/* * allocate a new signal queue record * - this may be called without locks if and only if t == current, otherwise an |
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* appropriate lock must be held to stop the target task from exiting |
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*/ |
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static struct sigqueue * __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit) |
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{ struct sigqueue *q = NULL; |
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struct user_struct *user; |
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|
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/* |
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* Protect access to @t credentials. This can go away when all * callers hold rcu read lock. |
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*/ |
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rcu_read_lock(); |
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user = get_uid(__task_cred(t)->user); |
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atomic_inc(&user->sigpending); |
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rcu_read_unlock(); |
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|
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if (override_rlimit || |
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atomic_read(&user->sigpending) <= |
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task_rlimit(t, RLIMIT_SIGPENDING)) { |
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q = kmem_cache_alloc(sigqueue_cachep, flags); |
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} else { print_dropped_signal(sig); } |
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if (unlikely(q == NULL)) { |
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atomic_dec(&user->sigpending); |
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free_uid(user); |
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} else { INIT_LIST_HEAD(&q->list); q->flags = 0; |
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q->user = user; |
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} |
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return q; |
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} |
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static void __sigqueue_free(struct sigqueue *q) |
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{ if (q->flags & SIGQUEUE_PREALLOC) return; atomic_dec(&q->user->sigpending); free_uid(q->user); kmem_cache_free(sigqueue_cachep, q); } |
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void flush_sigqueue(struct sigpending *queue) |
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{ struct sigqueue *q; sigemptyset(&queue->signal); while (!list_empty(&queue->list)) { q = list_entry(queue->list.next, struct sigqueue , list); list_del_init(&q->list); __sigqueue_free(q); } } /* * Flush all pending signals for a task. */ |
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void __flush_signals(struct task_struct *t) { clear_tsk_thread_flag(t, TIF_SIGPENDING); flush_sigqueue(&t->pending); flush_sigqueue(&t->signal->shared_pending); } |
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void flush_signals(struct task_struct *t) |
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{ unsigned long flags; spin_lock_irqsave(&t->sighand->siglock, flags); |
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__flush_signals(t); |
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spin_unlock_irqrestore(&t->sighand->siglock, flags); } |
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static void __flush_itimer_signals(struct sigpending *pending) { sigset_t signal, retain; struct sigqueue *q, *n; signal = pending->signal; sigemptyset(&retain); list_for_each_entry_safe(q, n, &pending->list, list) { int sig = q->info.si_signo; if (likely(q->info.si_code != SI_TIMER)) { sigaddset(&retain, sig); } else { sigdelset(&signal, sig); list_del_init(&q->list); __sigqueue_free(q); } } sigorsets(&pending->signal, &signal, &retain); } void flush_itimer_signals(void) { struct task_struct *tsk = current; unsigned long flags; spin_lock_irqsave(&tsk->sighand->siglock, flags); __flush_itimer_signals(&tsk->pending); __flush_itimer_signals(&tsk->signal->shared_pending); spin_unlock_irqrestore(&tsk->sighand->siglock, flags); } |
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void ignore_signals(struct task_struct *t) { int i; for (i = 0; i < _NSIG; ++i) t->sighand->action[i].sa.sa_handler = SIG_IGN; flush_signals(t); } |
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/* |
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* Flush all handlers for a task. */ void flush_signal_handlers(struct task_struct *t, int force_default) { int i; struct k_sigaction *ka = &t->sighand->action[0]; for (i = _NSIG ; i != 0 ; i--) { if (force_default || ka->sa.sa_handler != SIG_IGN) ka->sa.sa_handler = SIG_DFL; ka->sa.sa_flags = 0; |
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#ifdef __ARCH_HAS_SA_RESTORER |
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ka->sa.sa_restorer = NULL; #endif |
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sigemptyset(&ka->sa.sa_mask); ka++; } } |
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int unhandled_signal(struct task_struct *tsk, int sig) { |
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void __user *handler = tsk->sighand->action[sig-1].sa.sa_handler; |
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if (is_global_init(tsk)) |
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return 1; |
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if (handler != SIG_IGN && handler != SIG_DFL) |
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return 0; |
a288eecce ptrace: kill triv... |
481 482 |
/* if ptraced, let the tracer determine */ return !tsk->ptrace; |
abd4f7505 x86: i386-show-un... |
483 |
} |
5aba085ed kernel/signal.c: ... |
484 485 |
/* * Notify the system that a driver wants to block all signals for this |
1da177e4c Linux-2.6.12-rc2 |
486 487 488 489 490 |
* process, and wants to be notified if any signals at all were to be * sent/acted upon. If the notifier routine returns non-zero, then the * signal will be acted upon after all. If the notifier routine returns 0, * then then signal will be blocked. Only one block per process is * allowed. priv is a pointer to private data that the notifier routine |
5aba085ed kernel/signal.c: ... |
491 492 |
* can use to determine if the signal should be blocked or not. */ |
1da177e4c Linux-2.6.12-rc2 |
493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 |
void block_all_signals(int (*notifier)(void *priv), void *priv, sigset_t *mask) { unsigned long flags; spin_lock_irqsave(¤t->sighand->siglock, flags); current->notifier_mask = mask; current->notifier_data = priv; current->notifier = notifier; spin_unlock_irqrestore(¤t->sighand->siglock, flags); } /* Notify the system that blocking has ended. */ void unblock_all_signals(void) { unsigned long flags; spin_lock_irqsave(¤t->sighand->siglock, flags); current->notifier = NULL; current->notifier_data = NULL; recalc_sigpending(); spin_unlock_irqrestore(¤t->sighand->siglock, flags); } |
100360f03 signals: change c... |
518 |
static void collect_signal(int sig, struct sigpending *list, siginfo_t *info) |
1da177e4c Linux-2.6.12-rc2 |
519 520 |
{ struct sigqueue *q, *first = NULL; |
1da177e4c Linux-2.6.12-rc2 |
521 |
|
1da177e4c Linux-2.6.12-rc2 |
522 523 524 525 526 527 |
/* * Collect the siginfo appropriate to this signal. Check if * there is another siginfo for the same signal. */ list_for_each_entry(q, &list->list, list) { if (q->info.si_signo == sig) { |
d44342076 signals: collect_... |
528 529 |
if (first) goto still_pending; |
1da177e4c Linux-2.6.12-rc2 |
530 531 532 |
first = q; } } |
d44342076 signals: collect_... |
533 534 |
sigdelset(&list->signal, sig); |
1da177e4c Linux-2.6.12-rc2 |
535 |
if (first) { |
d44342076 signals: collect_... |
536 |
still_pending: |
1da177e4c Linux-2.6.12-rc2 |
537 538 539 |
list_del_init(&first->list); copy_siginfo(info, &first->info); __sigqueue_free(first); |
1da177e4c Linux-2.6.12-rc2 |
540 |
} else { |
5aba085ed kernel/signal.c: ... |
541 542 543 544 |
/* * Ok, it wasn't in the queue. This must be * a fast-pathed signal or we must have been * out of queue space. So zero out the info. |
1da177e4c Linux-2.6.12-rc2 |
545 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
546 547 |
info->si_signo = sig; info->si_errno = 0; |
7486e5d9f signals: cosmetic... |
548 |
info->si_code = SI_USER; |
1da177e4c Linux-2.6.12-rc2 |
549 550 551 |
info->si_pid = 0; info->si_uid = 0; } |
1da177e4c Linux-2.6.12-rc2 |
552 553 554 555 556 |
} static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, siginfo_t *info) { |
27d91e07f [PATCH] __dequeue... |
557 |
int sig = next_signal(pending, mask); |
1da177e4c Linux-2.6.12-rc2 |
558 |
|
1da177e4c Linux-2.6.12-rc2 |
559 560 561 562 563 564 565 566 567 |
if (sig) { if (current->notifier) { if (sigismember(current->notifier_mask, sig)) { if (!(current->notifier)(current->notifier_data)) { clear_thread_flag(TIF_SIGPENDING); return 0; } } } |
100360f03 signals: change c... |
568 |
collect_signal(sig, pending, info); |
1da177e4c Linux-2.6.12-rc2 |
569 |
} |
1da177e4c Linux-2.6.12-rc2 |
570 571 572 573 574 |
return sig; } /* |
5aba085ed kernel/signal.c: ... |
575 |
* Dequeue a signal and return the element to the caller, which is |
1da177e4c Linux-2.6.12-rc2 |
576 577 578 579 580 581 |
* expected to free it. * * All callers have to hold the siglock. */ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) { |
c5363d036 signals: clean de... |
582 |
int signr; |
caec4e8dc Fix signalfd inte... |
583 584 585 586 |
/* We only dequeue private signals from ourselves, we don't let * signalfd steal them */ |
b8fceee17 signalfd simplifi... |
587 |
signr = __dequeue_signal(&tsk->pending, mask, info); |
8bfd9a7a2 [PATCH] hrtimers:... |
588 |
if (!signr) { |
1da177e4c Linux-2.6.12-rc2 |
589 590 |
signr = __dequeue_signal(&tsk->signal->shared_pending, mask, info); |
8bfd9a7a2 [PATCH] hrtimers:... |
591 592 593 594 595 596 |
/* * itimer signal ? * * itimers are process shared and we restart periodic * itimers in the signal delivery path to prevent DoS * attacks in the high resolution timer case. This is |
5aba085ed kernel/signal.c: ... |
597 |
* compliant with the old way of self-restarting |
8bfd9a7a2 [PATCH] hrtimers:... |
598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 |
* itimers, as the SIGALRM is a legacy signal and only * queued once. Changing the restart behaviour to * restart the timer in the signal dequeue path is * reducing the timer noise on heavy loaded !highres * systems too. */ if (unlikely(signr == SIGALRM)) { struct hrtimer *tmr = &tsk->signal->real_timer; if (!hrtimer_is_queued(tmr) && tsk->signal->it_real_incr.tv64 != 0) { hrtimer_forward(tmr, tmr->base->get_time(), tsk->signal->it_real_incr); hrtimer_restart(tmr); } } } |
c5363d036 signals: clean de... |
615 |
|
b8fceee17 signalfd simplifi... |
616 |
recalc_sigpending(); |
c5363d036 signals: clean de... |
617 618 619 620 |
if (!signr) return 0; if (unlikely(sig_kernel_stop(signr))) { |
8bfd9a7a2 [PATCH] hrtimers:... |
621 622 623 624 625 626 627 628 629 630 631 632 |
/* * Set a marker that we have dequeued a stop signal. Our * caller might release the siglock and then the pending * stop signal it is about to process is no longer in the * pending bitmasks, but must still be cleared by a SIGCONT * (and overruled by a SIGKILL). So those cases clear this * shared flag after we've set it. Note that this flag may * remain set after the signal we return is ignored or * handled. That doesn't matter because its only purpose * is to alert stop-signal processing code when another * processor has come along and cleared the flag. */ |
a8f072c1d job control: rena... |
633 |
current->jobctl |= JOBCTL_STOP_DEQUEUED; |
8bfd9a7a2 [PATCH] hrtimers:... |
634 |
} |
c5363d036 signals: clean de... |
635 |
if ((info->si_code & __SI_MASK) == __SI_TIMER && info->si_sys_private) { |
1da177e4c Linux-2.6.12-rc2 |
636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 |
/* * Release the siglock to ensure proper locking order * of timer locks outside of siglocks. Note, we leave * irqs disabled here, since the posix-timers code is * about to disable them again anyway. */ spin_unlock(&tsk->sighand->siglock); do_schedule_next_timer(info); spin_lock(&tsk->sighand->siglock); } return signr; } /* * Tell a process that it has a new active signal.. * * NOTE! we rely on the previous spin_lock to * lock interrupts for us! We can only be called with * "siglock" held, and the local interrupt must * have been disabled when that got acquired! * * No need to set need_resched since signal event passing * goes through ->blocked */ |
910ffdb18 ptrace: introduce... |
660 |
void signal_wake_up_state(struct task_struct *t, unsigned int state) |
1da177e4c Linux-2.6.12-rc2 |
661 |
{ |
1da177e4c Linux-2.6.12-rc2 |
662 |
set_tsk_thread_flag(t, TIF_SIGPENDING); |
1da177e4c Linux-2.6.12-rc2 |
663 |
/* |
910ffdb18 ptrace: introduce... |
664 |
* TASK_WAKEKILL also means wake it up in the stopped/traced/killable |
f021a3c2b Add TASK_WAKEKILL |
665 |
* case. We don't check t->state here because there is a race with it |
1da177e4c Linux-2.6.12-rc2 |
666 667 668 669 |
* executing another processor and just now entering stopped state. * By using wake_up_state, we ensure the process will wake up and * handle its death signal. */ |
910ffdb18 ptrace: introduce... |
670 |
if (!wake_up_state(t, state | TASK_INTERRUPTIBLE)) |
1da177e4c Linux-2.6.12-rc2 |
671 672 673 674 675 676 677 678 |
kick_process(t); } /* * Remove signals in mask from the pending set and queue. * Returns 1 if any signals were found. * * All callers must be holding the siglock. |
71fabd5e4 [PATCH] sigaction... |
679 680 681 682 683 684 685 686 687 688 689 690 |
* * This version takes a sigset mask and looks at all signals, * not just those in the first mask word. */ static int rm_from_queue_full(sigset_t *mask, struct sigpending *s) { struct sigqueue *q, *n; sigset_t m; sigandsets(&m, mask, &s->signal); if (sigisemptyset(&m)) return 0; |
702a5073f signal: rename si... |
691 |
sigandnsets(&s->signal, &s->signal, mask); |
71fabd5e4 [PATCH] sigaction... |
692 693 694 695 696 697 698 699 700 701 702 703 704 |
list_for_each_entry_safe(q, n, &s->list, list) { if (sigismember(mask, q->info.si_signo)) { list_del_init(&q->list); __sigqueue_free(q); } } return 1; } /* * Remove signals in mask from the pending set and queue. * Returns 1 if any signals were found. * * All callers must be holding the siglock. |
1da177e4c Linux-2.6.12-rc2 |
705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 |
*/ static int rm_from_queue(unsigned long mask, struct sigpending *s) { struct sigqueue *q, *n; if (!sigtestsetmask(&s->signal, mask)) return 0; sigdelsetmask(&s->signal, mask); list_for_each_entry_safe(q, n, &s->list, list) { if (q->info.si_signo < SIGRTMIN && (mask & sigmask(q->info.si_signo))) { list_del_init(&q->list); __sigqueue_free(q); } } return 1; } |
614c517d7 signals: SEND_SIG... |
723 724 725 726 727 728 729 730 731 732 |
static inline int is_si_special(const struct siginfo *info) { return info <= SEND_SIG_FORCED; } static inline bool si_fromuser(const struct siginfo *info) { return info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info)); } |
1da177e4c Linux-2.6.12-rc2 |
733 |
/* |
39fd33933 userns: allow kil... |
734 735 736 737 738 739 |
* called with RCU read lock from check_kill_permission() */ static int kill_ok_by_cred(struct task_struct *t) { const struct cred *cred = current_cred(); const struct cred *tcred = __task_cred(t); |
5af662030 userns: Convert p... |
740 741 742 743 |
if (uid_eq(cred->euid, tcred->suid) || uid_eq(cred->euid, tcred->uid) || uid_eq(cred->uid, tcred->suid) || uid_eq(cred->uid, tcred->uid)) |
39fd33933 userns: allow kil... |
744 |
return 1; |
c4a4d6037 userns: Use cred-... |
745 |
if (ns_capable(tcred->user_ns, CAP_KILL)) |
39fd33933 userns: allow kil... |
746 747 748 749 750 751 |
return 1; return 0; } /* |
1da177e4c Linux-2.6.12-rc2 |
752 |
* Bad permissions for sending the signal |
694f690d2 CRED: Fix RCU war... |
753 |
* - the caller must hold the RCU read lock |
1da177e4c Linux-2.6.12-rc2 |
754 755 756 757 |
*/ static int check_kill_permission(int sig, struct siginfo *info, struct task_struct *t) { |
2e2ba22ea signals: check_ki... |
758 |
struct pid *sid; |
3b5e9e53c signals: cleanup ... |
759 |
int error; |
7ed20e1ad [PATCH] convert t... |
760 |
if (!valid_signal(sig)) |
3b5e9e53c signals: cleanup ... |
761 |
return -EINVAL; |
614c517d7 signals: SEND_SIG... |
762 |
if (!si_fromuser(info)) |
3b5e9e53c signals: cleanup ... |
763 |
return 0; |
e54dc2431 [PATCH] audit sig... |
764 |
|
3b5e9e53c signals: cleanup ... |
765 766 |
error = audit_signal_info(sig, t); /* Let audit system see the signal */ if (error) |
1da177e4c Linux-2.6.12-rc2 |
767 |
return error; |
3b5e9e53c signals: cleanup ... |
768 |
|
065add394 signals: check_ki... |
769 |
if (!same_thread_group(current, t) && |
39fd33933 userns: allow kil... |
770 |
!kill_ok_by_cred(t)) { |
2e2ba22ea signals: check_ki... |
771 772 |
switch (sig) { case SIGCONT: |
2e2ba22ea signals: check_ki... |
773 |
sid = task_session(t); |
2e2ba22ea signals: check_ki... |
774 775 776 777 778 779 780 781 782 783 |
/* * We don't return the error if sid == NULL. The * task was unhashed, the caller must notice this. */ if (!sid || sid == task_session(current)) break; default: return -EPERM; } } |
c2f0c7c35 The attached patc... |
784 |
|
e54dc2431 [PATCH] audit sig... |
785 |
return security_task_kill(t, info, sig, 0); |
1da177e4c Linux-2.6.12-rc2 |
786 |
} |
fb1d910c1 ptrace: implement... |
787 788 789 790 791 792 793 794 |
/** * ptrace_trap_notify - schedule trap to notify ptracer * @t: tracee wanting to notify tracer * * This function schedules sticky ptrace trap which is cleared on the next * TRAP_STOP to notify ptracer of an event. @t must have been seized by * ptracer. * |
544b2c91a ptrace: implement... |
795 796 797 798 799 |
* If @t is running, STOP trap will be taken. If trapped for STOP and * ptracer is listening for events, tracee is woken up so that it can * re-trap for the new event. If trapped otherwise, STOP trap will be * eventually taken without returning to userland after the existing traps * are finished by PTRACE_CONT. |
fb1d910c1 ptrace: implement... |
800 801 802 803 804 805 806 807 808 809 |
* * CONTEXT: * Must be called with @task->sighand->siglock held. */ static void ptrace_trap_notify(struct task_struct *t) { WARN_ON_ONCE(!(t->ptrace & PT_SEIZED)); assert_spin_locked(&t->sighand->siglock); task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY); |
910ffdb18 ptrace: introduce... |
810 |
ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING); |
fb1d910c1 ptrace: implement... |
811 |
} |
1da177e4c Linux-2.6.12-rc2 |
812 |
/* |
7e695a5ef signals: fold sig... |
813 814 |
* Handle magic process-wide effects of stop/continue signals. Unlike * the signal actions, these happen immediately at signal-generation |
1da177e4c Linux-2.6.12-rc2 |
815 816 |
* time regardless of blocking, ignoring, or handling. This does the * actual continuing for SIGCONT, but not the actual stopping for stop |
7e695a5ef signals: fold sig... |
817 818 819 820 |
* signals. The process stop is done as a signal action for SIG_DFL. * * Returns true if the signal should be actually delivered, otherwise * it should be dropped. |
1da177e4c Linux-2.6.12-rc2 |
821 |
*/ |
def8cf725 signal: cosmetic,... |
822 |
static int prepare_signal(int sig, struct task_struct *p, bool force) |
1da177e4c Linux-2.6.12-rc2 |
823 |
{ |
ad16a4606 handle_stop_signa... |
824 |
struct signal_struct *signal = p->signal; |
1da177e4c Linux-2.6.12-rc2 |
825 |
struct task_struct *t; |
7e695a5ef signals: fold sig... |
826 |
if (unlikely(signal->flags & SIGNAL_GROUP_EXIT)) { |
1da177e4c Linux-2.6.12-rc2 |
827 |
/* |
7e695a5ef signals: fold sig... |
828 |
* The process is in the middle of dying, nothing to do. |
1da177e4c Linux-2.6.12-rc2 |
829 |
*/ |
7e695a5ef signals: fold sig... |
830 |
} else if (sig_kernel_stop(sig)) { |
1da177e4c Linux-2.6.12-rc2 |
831 832 833 |
/* * This is a stop signal. Remove SIGCONT from all queues. */ |
ad16a4606 handle_stop_signa... |
834 |
rm_from_queue(sigmask(SIGCONT), &signal->shared_pending); |
1da177e4c Linux-2.6.12-rc2 |
835 836 837 |
t = p; do { rm_from_queue(sigmask(SIGCONT), &t->pending); |
ad16a4606 handle_stop_signa... |
838 |
} while_each_thread(p, t); |
1da177e4c Linux-2.6.12-rc2 |
839 |
} else if (sig == SIGCONT) { |
fc321d2e6 handle_stop_signa... |
840 |
unsigned int why; |
1da177e4c Linux-2.6.12-rc2 |
841 |
/* |
1deac632f signal: prepare_s... |
842 |
* Remove all stop signals from all queues, wake all threads. |
1da177e4c Linux-2.6.12-rc2 |
843 |
*/ |
ad16a4606 handle_stop_signa... |
844 |
rm_from_queue(SIG_KERNEL_STOP_MASK, &signal->shared_pending); |
1da177e4c Linux-2.6.12-rc2 |
845 846 |
t = p; do { |
3759a0d94 job control: intr... |
847 |
task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING); |
1da177e4c Linux-2.6.12-rc2 |
848 |
rm_from_queue(SIG_KERNEL_STOP_MASK, &t->pending); |
fb1d910c1 ptrace: implement... |
849 850 851 852 |
if (likely(!(t->ptrace & PT_SEIZED))) wake_up_state(t, __TASK_STOPPED); else ptrace_trap_notify(t); |
ad16a4606 handle_stop_signa... |
853 |
} while_each_thread(p, t); |
1da177e4c Linux-2.6.12-rc2 |
854 |
|
fc321d2e6 handle_stop_signa... |
855 856 857 858 859 860 861 862 863 |
/* * Notify the parent with CLD_CONTINUED if we were stopped. * * If we were in the middle of a group stop, we pretend it * was already finished, and then continued. Since SIGCHLD * doesn't queue we report only CLD_STOPPED, as if the next * CLD_CONTINUED was dropped. */ why = 0; |
ad16a4606 handle_stop_signa... |
864 |
if (signal->flags & SIGNAL_STOP_STOPPED) |
fc321d2e6 handle_stop_signa... |
865 |
why |= SIGNAL_CLD_CONTINUED; |
ad16a4606 handle_stop_signa... |
866 |
else if (signal->group_stop_count) |
fc321d2e6 handle_stop_signa... |
867 868 869 |
why |= SIGNAL_CLD_STOPPED; if (why) { |
021e1ae3d signals: document... |
870 |
/* |
ae6d2ed7b signals: tracehoo... |
871 |
* The first thread which returns from do_signal_stop() |
021e1ae3d signals: document... |
872 873 874 |
* will take ->siglock, notice SIGNAL_CLD_MASK, and * notify its parent. See get_signal_to_deliver(). */ |
ad16a4606 handle_stop_signa... |
875 876 877 |
signal->flags = why | SIGNAL_STOP_CONTINUED; signal->group_stop_count = 0; signal->group_exit_code = 0; |
1da177e4c Linux-2.6.12-rc2 |
878 |
} |
1da177e4c Linux-2.6.12-rc2 |
879 |
} |
7e695a5ef signals: fold sig... |
880 |
|
def8cf725 signal: cosmetic,... |
881 |
return !sig_ignored(p, sig, force); |
1da177e4c Linux-2.6.12-rc2 |
882 |
} |
71f11dc02 signals: move the... |
883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 |
/* * Test if P wants to take SIG. After we've checked all threads with this, * it's equivalent to finding no threads not blocking SIG. Any threads not * blocking SIG were ruled out because they are not running and already * have pending signals. Such threads will dequeue from the shared queue * as soon as they're available, so putting the signal on the shared queue * will be equivalent to sending it to one such thread. */ static inline int wants_signal(int sig, struct task_struct *p) { if (sigismember(&p->blocked, sig)) return 0; if (p->flags & PF_EXITING) return 0; if (sig == SIGKILL) return 1; if (task_is_stopped_or_traced(p)) return 0; return task_curr(p) || !signal_pending(p); } |
5fcd835bf signals: use __gr... |
903 |
static void complete_signal(int sig, struct task_struct *p, int group) |
71f11dc02 signals: move the... |
904 905 906 907 908 909 910 911 912 913 914 915 |
{ struct signal_struct *signal = p->signal; struct task_struct *t; /* * Now find a thread we can wake up to take the signal off the queue. * * If the main thread wants the signal, it gets first crack. * Probably the least surprising to the average bear. */ if (wants_signal(sig, p)) t = p; |
5fcd835bf signals: use __gr... |
916 |
else if (!group || thread_group_empty(p)) |
71f11dc02 signals: move the... |
917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 |
/* * There is just one thread and it does not need to be woken. * It will dequeue unblocked signals before it runs again. */ return; else { /* * Otherwise try to find a suitable thread. */ t = signal->curr_target; while (!wants_signal(sig, t)) { t = next_thread(t); if (t == signal->curr_target) /* * No thread needs to be woken. * Any eligible threads will see * the signal in the queue soon. */ return; } signal->curr_target = t; } /* * Found a killable thread. If the signal will be fatal, * then start taking the whole group down immediately. */ |
fae5fa44f signals: fix /sbi... |
944 945 |
if (sig_fatal(p, sig) && !(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) && |
71f11dc02 signals: move the... |
946 |
!sigismember(&t->real_blocked, sig) && |
a288eecce ptrace: kill triv... |
947 |
(sig == SIGKILL || !t->ptrace)) { |
71f11dc02 signals: move the... |
948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 |
/* * This signal will be fatal to the whole group. */ if (!sig_kernel_coredump(sig)) { /* * Start a group exit and wake everybody up. * This way we don't have other threads * running and doing things after a slower * thread has the fatal signal pending. */ signal->flags = SIGNAL_GROUP_EXIT; signal->group_exit_code = sig; signal->group_stop_count = 0; t = p; do { |
6dfca3298 job control: make... |
963 |
task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); |
71f11dc02 signals: move the... |
964 965 966 967 968 969 970 971 972 973 974 975 976 977 |
sigaddset(&t->pending.signal, SIGKILL); signal_wake_up(t, 1); } while_each_thread(p, t); return; } } /* * The signal is already in the shared-pending queue. * Tell the chosen thread to wake up and dequeue it. */ signal_wake_up(t, sig == SIGKILL); return; } |
af7fff9c1 signals: turn LEG... |
978 979 980 981 |
static inline int legacy_queue(struct sigpending *signals, int sig) { return (sig < SIGRTMIN) && sigismember(&signals->signal, sig); } |
6b550f949 user namespace: m... |
982 983 984 985 986 987 988 989 |
#ifdef CONFIG_USER_NS static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t) { if (current_user_ns() == task_cred_xxx(t, user_ns)) return; if (SI_FROMKERNEL(info)) return; |
078de5f70 userns: Store uid... |
990 991 992 993 |
rcu_read_lock(); info->si_uid = from_kuid_munged(task_cred_xxx(t, user_ns), make_kuid(current_user_ns(), info->si_uid)); rcu_read_unlock(); |
6b550f949 user namespace: m... |
994 995 996 997 998 999 1000 |
} #else static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t) { return; } #endif |
7978b567d signals: add from... |
1001 1002 |
static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, int group, int from_ancestor_ns) |
1da177e4c Linux-2.6.12-rc2 |
1003 |
{ |
2ca3515aa signals: change s... |
1004 |
struct sigpending *pending; |
6e65acba7 signals: move han... |
1005 |
struct sigqueue *q; |
7a0aeb14e signal: fix __sen... |
1006 |
int override_rlimit; |
6c303d3ab tracing: let trac... |
1007 |
int ret = 0, result; |
0a16b6075 tracing, sched: L... |
1008 |
|
6e65acba7 signals: move han... |
1009 |
assert_spin_locked(&t->sighand->siglock); |
921cf9f63 signals: protect ... |
1010 |
|
6c303d3ab tracing: let trac... |
1011 |
result = TRACE_SIGNAL_IGNORED; |
629d362b9 signal: give SEND... |
1012 1013 |
if (!prepare_signal(sig, t, from_ancestor_ns || (info == SEND_SIG_FORCED))) |
6c303d3ab tracing: let trac... |
1014 |
goto ret; |
2ca3515aa signals: change s... |
1015 1016 |
pending = group ? &t->signal->shared_pending : &t->pending; |
1da177e4c Linux-2.6.12-rc2 |
1017 |
/* |
2acb024d5 signals: consolid... |
1018 1019 1020 1021 |
* Short-circuit ignored signals and support queuing * exactly one non-rt signal, so that we can get more * detailed information about the cause of the signal. */ |
6c303d3ab tracing: let trac... |
1022 |
result = TRACE_SIGNAL_ALREADY_PENDING; |
7e695a5ef signals: fold sig... |
1023 |
if (legacy_queue(pending, sig)) |
6c303d3ab tracing: let trac... |
1024 1025 1026 |
goto ret; result = TRACE_SIGNAL_DELIVERED; |
fba2afaae signal/timer/even... |
1027 |
/* |
1da177e4c Linux-2.6.12-rc2 |
1028 1029 1030 |
* fast-pathed signals for kernel-internal things like SIGSTOP * or SIGKILL. */ |
b67a1b9e4 [PATCH] remove ha... |
1031 |
if (info == SEND_SIG_FORCED) |
1da177e4c Linux-2.6.12-rc2 |
1032 |
goto out_set; |
5aba085ed kernel/signal.c: ... |
1033 1034 1035 1036 1037 1038 1039 1040 1041 |
/* * Real-time signals must be queued if sent by sigqueue, or * some other real-time mechanism. It is implementation * defined whether kill() does so. We attempt to do so, on * the principle of least surprise, but since kill is not * allowed to fail with EAGAIN when low on memory we just * make sure at least one signal gets delivered and don't * pass on the info struct. */ |
7a0aeb14e signal: fix __sen... |
1042 1043 1044 1045 |
if (sig < SIGRTMIN) override_rlimit = (is_si_special(info) || info->si_code >= 0); else override_rlimit = 0; |
f84d49b21 signal: Print war... |
1046 |
q = __sigqueue_alloc(sig, t, GFP_ATOMIC | __GFP_NOTRACK_FALSE_POSITIVE, |
7a0aeb14e signal: fix __sen... |
1047 |
override_rlimit); |
1da177e4c Linux-2.6.12-rc2 |
1048 |
if (q) { |
2ca3515aa signals: change s... |
1049 |
list_add_tail(&q->list, &pending->list); |
1da177e4c Linux-2.6.12-rc2 |
1050 |
switch ((unsigned long) info) { |
b67a1b9e4 [PATCH] remove ha... |
1051 |
case (unsigned long) SEND_SIG_NOINFO: |
1da177e4c Linux-2.6.12-rc2 |
1052 1053 1054 |
q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_USER; |
9cd4fd104 SEND_SIG_NOINFO: ... |
1055 |
q->info.si_pid = task_tgid_nr_ns(current, |
09bca05c9 SEND_SIG_NOINFO: ... |
1056 |
task_active_pid_ns(t)); |
078de5f70 userns: Store uid... |
1057 |
q->info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); |
1da177e4c Linux-2.6.12-rc2 |
1058 |
break; |
b67a1b9e4 [PATCH] remove ha... |
1059 |
case (unsigned long) SEND_SIG_PRIV: |
1da177e4c Linux-2.6.12-rc2 |
1060 1061 1062 1063 1064 1065 1066 1067 |
q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_KERNEL; q->info.si_pid = 0; q->info.si_uid = 0; break; default: copy_siginfo(&q->info, info); |
6588c1e3f signals: SI_USER:... |
1068 1069 |
if (from_ancestor_ns) q->info.si_pid = 0; |
1da177e4c Linux-2.6.12-rc2 |
1070 1071 |
break; } |
6b550f949 user namespace: m... |
1072 1073 |
userns_fixup_signal_uid(&q->info, t); |
621d31219 [PATCH] cleanup t... |
1074 |
} else if (!is_si_special(info)) { |
ba005e1f4 tracepoint: Add s... |
1075 1076 1077 1078 1079 1080 |
if (sig >= SIGRTMIN && info->si_code != SI_USER) { /* * Queue overflow, abort. We may abort if the * signal was rt and sent by user using something * other than kill(). */ |
6c303d3ab tracing: let trac... |
1081 1082 1083 |
result = TRACE_SIGNAL_OVERFLOW_FAIL; ret = -EAGAIN; goto ret; |
ba005e1f4 tracepoint: Add s... |
1084 1085 1086 1087 1088 |
} else { /* * This is a silent loss of information. We still * send the signal, but the *info bits are lost. */ |
6c303d3ab tracing: let trac... |
1089 |
result = TRACE_SIGNAL_LOSE_INFO; |
ba005e1f4 tracepoint: Add s... |
1090 |
} |
1da177e4c Linux-2.6.12-rc2 |
1091 1092 1093 |
} out_set: |
53c30337f signals: send_sig... |
1094 |
signalfd_notify(t, sig); |
2ca3515aa signals: change s... |
1095 |
sigaddset(&pending->signal, sig); |
4cd4b6d4e signals: fold com... |
1096 |
complete_signal(sig, t, group); |
6c303d3ab tracing: let trac... |
1097 1098 1099 |
ret: trace_signal_generate(sig, info, t, group, result); return ret; |
1da177e4c Linux-2.6.12-rc2 |
1100 |
} |
7978b567d signals: add from... |
1101 1102 1103 |
static int send_signal(int sig, struct siginfo *info, struct task_struct *t, int group) { |
921cf9f63 signals: protect ... |
1104 1105 1106 |
int from_ancestor_ns = 0; #ifdef CONFIG_PID_NS |
dd34200ad signals: send_sig... |
1107 1108 |
from_ancestor_ns = si_fromuser(info) && !task_pid_nr_ns(current, task_active_pid_ns(t)); |
921cf9f63 signals: protect ... |
1109 1110 1111 |
#endif return __send_signal(sig, info, t, group, from_ancestor_ns); |
7978b567d signals: add from... |
1112 |
} |
4aaefee58 print_fatal_signa... |
1113 |
static void print_fatal_signal(int signr) |
45807a1df vdso: print fatal... |
1114 |
{ |
4aaefee58 print_fatal_signa... |
1115 |
struct pt_regs *regs = signal_pt_regs(); |
5d1fadc14 kernel/signal.c: ... |
1116 1117 |
printk(KERN_INFO "%s/%d: potentially unexpected fatal signal %d. ", |
ba25f9dcc Use helpers to ob... |
1118 |
current->comm, task_pid_nr(current), signr); |
45807a1df vdso: print fatal... |
1119 |
|
ca5cd877a x86 merge fallout... |
1120 |
#if defined(__i386__) && !defined(__arch_um__) |
5d1fadc14 kernel/signal.c: ... |
1121 |
printk(KERN_INFO "code at %08lx: ", regs->ip); |
45807a1df vdso: print fatal... |
1122 1123 1124 1125 |
{ int i; for (i = 0; i < 16; i++) { unsigned char insn; |
b45c6e76b kernel/signal.c: ... |
1126 1127 |
if (get_user(insn, (unsigned char *)(regs->ip + i))) break; |
5d1fadc14 kernel/signal.c: ... |
1128 |
printk(KERN_CONT "%02x ", insn); |
45807a1df vdso: print fatal... |
1129 1130 |
} } |
5d1fadc14 kernel/signal.c: ... |
1131 1132 |
printk(KERN_CONT " "); |
45807a1df vdso: print fatal... |
1133 |
#endif |
3a9f84d35 signals, debug: f... |
1134 |
preempt_disable(); |
45807a1df vdso: print fatal... |
1135 |
show_regs(regs); |
3a9f84d35 signals, debug: f... |
1136 |
preempt_enable(); |
45807a1df vdso: print fatal... |
1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 |
} static int __init setup_print_fatal_signals(char *str) { get_option (&str, &print_fatal_signals); return 1; } __setup("print-fatal-signals=", setup_print_fatal_signals); |
1da177e4c Linux-2.6.12-rc2 |
1147 |
|
4cd4b6d4e signals: fold com... |
1148 1149 1150 1151 1152 |
int __group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { return send_signal(sig, info, p, 1); } |
1da177e4c Linux-2.6.12-rc2 |
1153 1154 1155 |
static int specific_send_sig_info(int sig, struct siginfo *info, struct task_struct *t) { |
4cd4b6d4e signals: fold com... |
1156 |
return send_signal(sig, info, t, 0); |
1da177e4c Linux-2.6.12-rc2 |
1157 |
} |
4a30debfb signals: introduc... |
1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 |
int do_send_sig_info(int sig, struct siginfo *info, struct task_struct *p, bool group) { unsigned long flags; int ret = -ESRCH; if (lock_task_sighand(p, &flags)) { ret = send_signal(sig, info, p, group); unlock_task_sighand(p, &flags); } return ret; } |
1da177e4c Linux-2.6.12-rc2 |
1171 1172 1173 |
/* * Force a signal that the process can't ignore: if necessary * we unblock the signal and change any SIG_IGN to SIG_DFL. |
ae74c3b69 Fix force_sig_inf... |
1174 1175 1176 1177 1178 |
* * Note: If we unblock the signal, we always reset it to SIG_DFL, * since we do not want to have a signal handler that was blocked * be invoked when user space had explicitly blocked it. * |
80fe728d5 signals: allow th... |
1179 1180 |
* We don't want to have recursive SIGSEGV's etc, for example, * that is why we also clear SIGNAL_UNKILLABLE. |
1da177e4c Linux-2.6.12-rc2 |
1181 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
1182 1183 1184 1185 |
int force_sig_info(int sig, struct siginfo *info, struct task_struct *t) { unsigned long int flags; |
ae74c3b69 Fix force_sig_inf... |
1186 1187 |
int ret, blocked, ignored; struct k_sigaction *action; |
1da177e4c Linux-2.6.12-rc2 |
1188 1189 |
spin_lock_irqsave(&t->sighand->siglock, flags); |
ae74c3b69 Fix force_sig_inf... |
1190 1191 1192 1193 1194 1195 1196 |
action = &t->sighand->action[sig-1]; ignored = action->sa.sa_handler == SIG_IGN; blocked = sigismember(&t->blocked, sig); if (blocked || ignored) { action->sa.sa_handler = SIG_DFL; if (blocked) { sigdelset(&t->blocked, sig); |
7bb44adef recalc_sigpending... |
1197 |
recalc_sigpending_and_wake(t); |
ae74c3b69 Fix force_sig_inf... |
1198 |
} |
1da177e4c Linux-2.6.12-rc2 |
1199 |
} |
80fe728d5 signals: allow th... |
1200 1201 |
if (action->sa.sa_handler == SIG_DFL) t->signal->flags &= ~SIGNAL_UNKILLABLE; |
1da177e4c Linux-2.6.12-rc2 |
1202 1203 1204 1205 1206 |
ret = specific_send_sig_info(sig, info, t); spin_unlock_irqrestore(&t->sighand->siglock, flags); return ret; } |
1da177e4c Linux-2.6.12-rc2 |
1207 1208 1209 |
/* * Nuke all other threads in the group. */ |
09faef11d exit: change zap_... |
1210 |
int zap_other_threads(struct task_struct *p) |
1da177e4c Linux-2.6.12-rc2 |
1211 |
{ |
09faef11d exit: change zap_... |
1212 1213 |
struct task_struct *t = p; int count = 0; |
1da177e4c Linux-2.6.12-rc2 |
1214 |
|
1da177e4c Linux-2.6.12-rc2 |
1215 |
p->signal->group_stop_count = 0; |
09faef11d exit: change zap_... |
1216 |
while_each_thread(p, t) { |
6dfca3298 job control: make... |
1217 |
task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); |
09faef11d exit: change zap_... |
1218 1219 1220 |
count++; /* Don't bother with already dead threads */ |
1da177e4c Linux-2.6.12-rc2 |
1221 1222 |
if (t->exit_state) continue; |
1da177e4c Linux-2.6.12-rc2 |
1223 |
sigaddset(&t->pending.signal, SIGKILL); |
1da177e4c Linux-2.6.12-rc2 |
1224 1225 |
signal_wake_up(t, 1); } |
09faef11d exit: change zap_... |
1226 1227 |
return count; |
1da177e4c Linux-2.6.12-rc2 |
1228 |
} |
b8ed374e2 signals: annotate... |
1229 1230 |
struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, unsigned long *flags) |
f63ee72e0 [PATCH] introduce... |
1231 1232 1233 1234 |
{ struct sighand_struct *sighand; for (;;) { |
a841796f1 signal: align __l... |
1235 1236 |
local_irq_save(*flags); rcu_read_lock(); |
f63ee72e0 [PATCH] introduce... |
1237 |
sighand = rcu_dereference(tsk->sighand); |
a841796f1 signal: align __l... |
1238 1239 1240 |
if (unlikely(sighand == NULL)) { rcu_read_unlock(); local_irq_restore(*flags); |
f63ee72e0 [PATCH] introduce... |
1241 |
break; |
a841796f1 signal: align __l... |
1242 |
} |
f63ee72e0 [PATCH] introduce... |
1243 |
|
a841796f1 signal: align __l... |
1244 1245 1246 |
spin_lock(&sighand->siglock); if (likely(sighand == tsk->sighand)) { rcu_read_unlock(); |
f63ee72e0 [PATCH] introduce... |
1247 |
break; |
a841796f1 signal: align __l... |
1248 1249 1250 1251 |
} spin_unlock(&sighand->siglock); rcu_read_unlock(); local_irq_restore(*flags); |
f63ee72e0 [PATCH] introduce... |
1252 1253 1254 1255 |
} return sighand; } |
c69e8d9c0 CRED: Use RCU to ... |
1256 1257 |
/* * send signal info to all the members of a group |
c69e8d9c0 CRED: Use RCU to ... |
1258 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
1259 1260 |
int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { |
694f690d2 CRED: Fix RCU war... |
1261 1262 1263 1264 1265 |
int ret; rcu_read_lock(); ret = check_kill_permission(sig, info, p); rcu_read_unlock(); |
f63ee72e0 [PATCH] introduce... |
1266 |
|
4a30debfb signals: introduc... |
1267 1268 |
if (!ret && sig) ret = do_send_sig_info(sig, info, p, true); |
1da177e4c Linux-2.6.12-rc2 |
1269 1270 1271 1272 1273 |
return ret; } /* |
146a505d4 Get rid of the ki... |
1274 |
* __kill_pgrp_info() sends a signal to a process group: this is what the tty |
1da177e4c Linux-2.6.12-rc2 |
1275 |
* control characters do (^C, ^Z etc) |
c69e8d9c0 CRED: Use RCU to ... |
1276 |
* - the caller must hold at least a readlock on tasklist_lock |
1da177e4c Linux-2.6.12-rc2 |
1277 |
*/ |
c4b92fc11 [PATCH] pid: impl... |
1278 |
int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp) |
1da177e4c Linux-2.6.12-rc2 |
1279 1280 1281 |
{ struct task_struct *p = NULL; int retval, success; |
1da177e4c Linux-2.6.12-rc2 |
1282 1283 |
success = 0; retval = -ESRCH; |
c4b92fc11 [PATCH] pid: impl... |
1284 |
do_each_pid_task(pgrp, PIDTYPE_PGID, p) { |
1da177e4c Linux-2.6.12-rc2 |
1285 1286 1287 |
int err = group_send_sig_info(sig, info, p); success |= !err; retval = err; |
c4b92fc11 [PATCH] pid: impl... |
1288 |
} while_each_pid_task(pgrp, PIDTYPE_PGID, p); |
1da177e4c Linux-2.6.12-rc2 |
1289 1290 |
return success ? 0 : retval; } |
c4b92fc11 [PATCH] pid: impl... |
1291 |
int kill_pid_info(int sig, struct siginfo *info, struct pid *pid) |
1da177e4c Linux-2.6.12-rc2 |
1292 |
{ |
d36174bc2 uglify kill_pid_i... |
1293 |
int error = -ESRCH; |
1da177e4c Linux-2.6.12-rc2 |
1294 |
struct task_struct *p; |
e56d09031 [PATCH] RCU signa... |
1295 |
rcu_read_lock(); |
d36174bc2 uglify kill_pid_i... |
1296 |
retry: |
c4b92fc11 [PATCH] pid: impl... |
1297 |
p = pid_task(pid, PIDTYPE_PID); |
d36174bc2 uglify kill_pid_i... |
1298 |
if (p) { |
1da177e4c Linux-2.6.12-rc2 |
1299 |
error = group_send_sig_info(sig, info, p); |
d36174bc2 uglify kill_pid_i... |
1300 1301 1302 1303 1304 1305 1306 1307 1308 |
if (unlikely(error == -ESRCH)) /* * The task was unhashed in between, try again. * If it is dead, pid_task() will return NULL, * if we race with de_thread() it will find the * new leader. */ goto retry; } |
e56d09031 [PATCH] RCU signa... |
1309 |
rcu_read_unlock(); |
6ca25b551 kill_pid_info: do... |
1310 |
|
1da177e4c Linux-2.6.12-rc2 |
1311 1312 |
return error; } |
5aba085ed kernel/signal.c: ... |
1313 |
int kill_proc_info(int sig, struct siginfo *info, pid_t pid) |
c4b92fc11 [PATCH] pid: impl... |
1314 1315 1316 |
{ int error; rcu_read_lock(); |
b488893a3 pid namespaces: c... |
1317 |
error = kill_pid_info(sig, info, find_vpid(pid)); |
c4b92fc11 [PATCH] pid: impl... |
1318 1319 1320 |
rcu_read_unlock(); return error; } |
d178bc3a7 user namespace: u... |
1321 1322 1323 1324 |
static int kill_as_cred_perm(const struct cred *cred, struct task_struct *target) { const struct cred *pcred = __task_cred(target); |
5af662030 userns: Convert p... |
1325 1326 |
if (!uid_eq(cred->euid, pcred->suid) && !uid_eq(cred->euid, pcred->uid) && !uid_eq(cred->uid, pcred->suid) && !uid_eq(cred->uid, pcred->uid)) |
d178bc3a7 user namespace: u... |
1327 1328 1329 |
return 0; return 1; } |
2425c08b3 [PATCH] usb: fixu... |
1330 |
/* like kill_pid_info(), but doesn't use uid/euid of "current" */ |
d178bc3a7 user namespace: u... |
1331 1332 |
int kill_pid_info_as_cred(int sig, struct siginfo *info, struct pid *pid, const struct cred *cred, u32 secid) |
46113830a [PATCH] Fix signa... |
1333 1334 1335 |
{ int ret = -EINVAL; struct task_struct *p; |
14d8c9f3c signal: Fix racy ... |
1336 |
unsigned long flags; |
46113830a [PATCH] Fix signa... |
1337 1338 1339 |
if (!valid_signal(sig)) return ret; |
14d8c9f3c signal: Fix racy ... |
1340 |
rcu_read_lock(); |
2425c08b3 [PATCH] usb: fixu... |
1341 |
p = pid_task(pid, PIDTYPE_PID); |
46113830a [PATCH] Fix signa... |
1342 1343 1344 1345 |
if (!p) { ret = -ESRCH; goto out_unlock; } |
d178bc3a7 user namespace: u... |
1346 |
if (si_fromuser(info) && !kill_as_cred_perm(cred, p)) { |
46113830a [PATCH] Fix signa... |
1347 1348 1349 |
ret = -EPERM; goto out_unlock; } |
8f95dc58d [PATCH] SELinux: ... |
1350 1351 1352 |
ret = security_task_kill(p, info, sig, secid); if (ret) goto out_unlock; |
14d8c9f3c signal: Fix racy ... |
1353 1354 1355 1356 1357 1358 1359 |
if (sig) { if (lock_task_sighand(p, &flags)) { ret = __send_signal(sig, info, p, 1, 0); unlock_task_sighand(p, &flags); } else ret = -ESRCH; |
46113830a [PATCH] Fix signa... |
1360 1361 |
} out_unlock: |
14d8c9f3c signal: Fix racy ... |
1362 |
rcu_read_unlock(); |
46113830a [PATCH] Fix signa... |
1363 1364 |
return ret; } |
d178bc3a7 user namespace: u... |
1365 |
EXPORT_SYMBOL_GPL(kill_pid_info_as_cred); |
1da177e4c Linux-2.6.12-rc2 |
1366 1367 1368 1369 1370 1371 1372 |
/* * kill_something_info() interprets pid in interesting ways just like kill(2). * * POSIX specifies that kill(-1,sig) is unspecified, but what we have * is probably wrong. Should make it like BSD or SYSV. */ |
bc64efd22 kernel/signal.c: ... |
1373 |
static int kill_something_info(int sig, struct siginfo *info, pid_t pid) |
1da177e4c Linux-2.6.12-rc2 |
1374 |
{ |
8d42db189 [PATCH] signal: r... |
1375 |
int ret; |
d5df763b8 Clean up the kill... |
1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 |
if (pid > 0) { rcu_read_lock(); ret = kill_pid_info(sig, info, find_vpid(pid)); rcu_read_unlock(); return ret; } read_lock(&tasklist_lock); if (pid != -1) { ret = __kill_pgrp_info(sig, info, pid ? find_vpid(-pid) : task_pgrp(current)); } else { |
1da177e4c Linux-2.6.12-rc2 |
1389 1390 |
int retval = 0, count = 0; struct task_struct * p; |
1da177e4c Linux-2.6.12-rc2 |
1391 |
for_each_process(p) { |
d25141a81 'kill sig -1' mus... |
1392 1393 |
if (task_pid_vnr(p) > 1 && !same_thread_group(p, current)) { |
1da177e4c Linux-2.6.12-rc2 |
1394 1395 1396 1397 1398 1399 |
int err = group_send_sig_info(sig, info, p); ++count; if (err != -EPERM) retval = err; } } |
8d42db189 [PATCH] signal: r... |
1400 |
ret = count ? retval : -ESRCH; |
1da177e4c Linux-2.6.12-rc2 |
1401 |
} |
d5df763b8 Clean up the kill... |
1402 |
read_unlock(&tasklist_lock); |
8d42db189 [PATCH] signal: r... |
1403 |
return ret; |
1da177e4c Linux-2.6.12-rc2 |
1404 1405 1406 1407 1408 |
} /* * These are for backward compatibility with the rest of the kernel source. */ |
5aba085ed kernel/signal.c: ... |
1409 |
int send_sig_info(int sig, struct siginfo *info, struct task_struct *p) |
1da177e4c Linux-2.6.12-rc2 |
1410 |
{ |
1da177e4c Linux-2.6.12-rc2 |
1411 1412 1413 1414 |
/* * Make sure legacy kernel users don't send in bad values * (normal paths check this in check_kill_permission). */ |
7ed20e1ad [PATCH] convert t... |
1415 |
if (!valid_signal(sig)) |
1da177e4c Linux-2.6.12-rc2 |
1416 |
return -EINVAL; |
4a30debfb signals: introduc... |
1417 |
return do_send_sig_info(sig, info, p, false); |
1da177e4c Linux-2.6.12-rc2 |
1418 |
} |
b67a1b9e4 [PATCH] remove ha... |
1419 1420 |
#define __si_special(priv) \ ((priv) ? SEND_SIG_PRIV : SEND_SIG_NOINFO) |
1da177e4c Linux-2.6.12-rc2 |
1421 1422 1423 |
int send_sig(int sig, struct task_struct *p, int priv) { |
b67a1b9e4 [PATCH] remove ha... |
1424 |
return send_sig_info(sig, __si_special(priv), p); |
1da177e4c Linux-2.6.12-rc2 |
1425 |
} |
1da177e4c Linux-2.6.12-rc2 |
1426 1427 1428 |
void force_sig(int sig, struct task_struct *p) { |
b67a1b9e4 [PATCH] remove ha... |
1429 |
force_sig_info(sig, SEND_SIG_PRIV, p); |
1da177e4c Linux-2.6.12-rc2 |
1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 |
} /* * When things go south during signal handling, we * will force a SIGSEGV. And if the signal that caused * the problem was already a SIGSEGV, we'll want to * make sure we don't even try to deliver the signal.. */ int force_sigsegv(int sig, struct task_struct *p) { if (sig == SIGSEGV) { unsigned long flags; spin_lock_irqsave(&p->sighand->siglock, flags); p->sighand->action[sig - 1].sa.sa_handler = SIG_DFL; spin_unlock_irqrestore(&p->sighand->siglock, flags); } force_sig(SIGSEGV, p); return 0; } |
c4b92fc11 [PATCH] pid: impl... |
1450 1451 |
int kill_pgrp(struct pid *pid, int sig, int priv) { |
146a505d4 Get rid of the ki... |
1452 1453 1454 1455 1456 1457 1458 |
int ret; read_lock(&tasklist_lock); ret = __kill_pgrp_info(sig, __si_special(priv), pid); read_unlock(&tasklist_lock); return ret; |
c4b92fc11 [PATCH] pid: impl... |
1459 1460 1461 1462 1463 1464 1465 1466 |
} EXPORT_SYMBOL(kill_pgrp); int kill_pid(struct pid *pid, int sig, int priv) { return kill_pid_info(sig, __si_special(priv), pid); } EXPORT_SYMBOL(kill_pid); |
1da177e4c Linux-2.6.12-rc2 |
1467 1468 1469 1470 |
/* * These functions support sending signals using preallocated sigqueue * structures. This is needed "because realtime applications cannot * afford to lose notifications of asynchronous events, like timer |
5aba085ed kernel/signal.c: ... |
1471 |
* expirations or I/O completions". In the case of POSIX Timers |
1da177e4c Linux-2.6.12-rc2 |
1472 1473 1474 1475 |
* we allocate the sigqueue structure from the timer_create. If this * allocation fails we are able to report the failure to the application * with an EAGAIN error. */ |
1da177e4c Linux-2.6.12-rc2 |
1476 1477 |
struct sigqueue *sigqueue_alloc(void) { |
f84d49b21 signal: Print war... |
1478 |
struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0); |
1da177e4c Linux-2.6.12-rc2 |
1479 |
|
f84d49b21 signal: Print war... |
1480 |
if (q) |
1da177e4c Linux-2.6.12-rc2 |
1481 |
q->flags |= SIGQUEUE_PREALLOC; |
f84d49b21 signal: Print war... |
1482 1483 |
return q; |
1da177e4c Linux-2.6.12-rc2 |
1484 1485 1486 1487 1488 |
} void sigqueue_free(struct sigqueue *q) { unsigned long flags; |
60187d270 sigqueue_free: fi... |
1489 |
spinlock_t *lock = ¤t->sighand->siglock; |
1da177e4c Linux-2.6.12-rc2 |
1490 1491 |
BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); /* |
c8e85b4f4 posix timers: sig... |
1492 1493 |
* We must hold ->siglock while testing q->list * to serialize with collect_signal() or with |
da7978b03 signals: fix sigq... |
1494 |
* __exit_signal()->flush_sigqueue(). |
1da177e4c Linux-2.6.12-rc2 |
1495 |
*/ |
60187d270 sigqueue_free: fi... |
1496 |
spin_lock_irqsave(lock, flags); |
c8e85b4f4 posix timers: sig... |
1497 1498 1499 1500 1501 |
q->flags &= ~SIGQUEUE_PREALLOC; /* * If it is queued it will be freed when dequeued, * like the "regular" sigqueue. */ |
60187d270 sigqueue_free: fi... |
1502 |
if (!list_empty(&q->list)) |
c8e85b4f4 posix timers: sig... |
1503 |
q = NULL; |
60187d270 sigqueue_free: fi... |
1504 |
spin_unlock_irqrestore(lock, flags); |
c8e85b4f4 posix timers: sig... |
1505 1506 |
if (q) __sigqueue_free(q); |
1da177e4c Linux-2.6.12-rc2 |
1507 |
} |
ac5c21538 signals: join sen... |
1508 |
int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group) |
9e3bd6c3f signals: consolid... |
1509 |
{ |
e62e6650e signals: unify se... |
1510 |
int sig = q->info.si_signo; |
2ca3515aa signals: change s... |
1511 |
struct sigpending *pending; |
e62e6650e signals: unify se... |
1512 |
unsigned long flags; |
163566f60 tracing: send_sig... |
1513 |
int ret, result; |
2ca3515aa signals: change s... |
1514 |
|
4cd4b6d4e signals: fold com... |
1515 |
BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); |
e62e6650e signals: unify se... |
1516 1517 1518 1519 |
ret = -1; if (!likely(lock_task_sighand(t, &flags))) goto ret; |
7e695a5ef signals: fold sig... |
1520 |
ret = 1; /* the signal is ignored */ |
163566f60 tracing: send_sig... |
1521 |
result = TRACE_SIGNAL_IGNORED; |
def8cf725 signal: cosmetic,... |
1522 |
if (!prepare_signal(sig, t, false)) |
e62e6650e signals: unify se... |
1523 1524 1525 |
goto out; ret = 0; |
9e3bd6c3f signals: consolid... |
1526 1527 1528 1529 1530 |
if (unlikely(!list_empty(&q->list))) { /* * If an SI_TIMER entry is already queue just increment * the overrun count. */ |
9e3bd6c3f signals: consolid... |
1531 1532 |
BUG_ON(q->info.si_code != SI_TIMER); q->info.si_overrun++; |
163566f60 tracing: send_sig... |
1533 |
result = TRACE_SIGNAL_ALREADY_PENDING; |
e62e6650e signals: unify se... |
1534 |
goto out; |
9e3bd6c3f signals: consolid... |
1535 |
} |
ba661292a posix-timers: fix... |
1536 |
q->info.si_overrun = 0; |
9e3bd6c3f signals: consolid... |
1537 |
|
9e3bd6c3f signals: consolid... |
1538 |
signalfd_notify(t, sig); |
2ca3515aa signals: change s... |
1539 |
pending = group ? &t->signal->shared_pending : &t->pending; |
9e3bd6c3f signals: consolid... |
1540 1541 |
list_add_tail(&q->list, &pending->list); sigaddset(&pending->signal, sig); |
4cd4b6d4e signals: fold com... |
1542 |
complete_signal(sig, t, group); |
163566f60 tracing: send_sig... |
1543 |
result = TRACE_SIGNAL_DELIVERED; |
e62e6650e signals: unify se... |
1544 |
out: |
163566f60 tracing: send_sig... |
1545 |
trace_signal_generate(sig, &q->info, t, group, result); |
e62e6650e signals: unify se... |
1546 1547 1548 |
unlock_task_sighand(t, &flags); ret: return ret; |
9e3bd6c3f signals: consolid... |
1549 |
} |
1da177e4c Linux-2.6.12-rc2 |
1550 |
/* |
1da177e4c Linux-2.6.12-rc2 |
1551 1552 |
* Let a parent know about the death of a child. * For a stopped/continued status change, use do_notify_parent_cldstop instead. |
2b2a1ff64 tracehook: death |
1553 |
* |
53c8f9f19 make do_notify_pa... |
1554 1555 |
* Returns true if our parent ignored us and so we've switched to * self-reaping. |
1da177e4c Linux-2.6.12-rc2 |
1556 |
*/ |
53c8f9f19 make do_notify_pa... |
1557 |
bool do_notify_parent(struct task_struct *tsk, int sig) |
1da177e4c Linux-2.6.12-rc2 |
1558 1559 1560 1561 |
{ struct siginfo info; unsigned long flags; struct sighand_struct *psig; |
53c8f9f19 make do_notify_pa... |
1562 |
bool autoreap = false; |
6fac4829c cputime: Use acce... |
1563 |
cputime_t utime, stime; |
1da177e4c Linux-2.6.12-rc2 |
1564 1565 1566 1567 |
BUG_ON(sig == -1); /* do_notify_parent_cldstop should have been called instead. */ |
e1abb39c6 signal: Use task_... |
1568 |
BUG_ON(task_is_stopped_or_traced(tsk)); |
1da177e4c Linux-2.6.12-rc2 |
1569 |
|
d21142ece ptrace: kill task... |
1570 |
BUG_ON(!tsk->ptrace && |
1da177e4c Linux-2.6.12-rc2 |
1571 |
(tsk->group_leader != tsk || !thread_group_empty(tsk))); |
b6e238dce exit_signal: fix ... |
1572 1573 1574 1575 1576 1577 1578 1579 |
if (sig != SIGCHLD) { /* * This is only possible if parent == real_parent. * Check if it has changed security domain. */ if (tsk->parent_exec_id != tsk->parent->self_exec_id) sig = SIGCHLD; } |
1da177e4c Linux-2.6.12-rc2 |
1580 1581 |
info.si_signo = sig; info.si_errno = 0; |
b488893a3 pid namespaces: c... |
1582 |
/* |
320845048 pidns: use task_a... |
1583 1584 |
* We are under tasklist_lock here so our parent is tied to * us and cannot change. |
b488893a3 pid namespaces: c... |
1585 |
* |
320845048 pidns: use task_a... |
1586 1587 |
* task_active_pid_ns will always return the same pid namespace * until a task passes through release_task. |
b488893a3 pid namespaces: c... |
1588 1589 1590 1591 1592 1593 |
* * write_lock() currently calls preempt_disable() which is the * same as rcu_read_lock(), but according to Oleg, this is not * correct to rely on this */ rcu_read_lock(); |
320845048 pidns: use task_a... |
1594 |
info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(tsk->parent)); |
54ba47eda userns: signal re... |
1595 1596 |
info.si_uid = from_kuid_munged(task_cred_xxx(tsk->parent, user_ns), task_uid(tsk)); |
b488893a3 pid namespaces: c... |
1597 |
rcu_read_unlock(); |
6fac4829c cputime: Use acce... |
1598 1599 1600 |
task_cputime(tsk, &utime, &stime); info.si_utime = cputime_to_clock_t(utime + tsk->signal->utime); info.si_stime = cputime_to_clock_t(stime + tsk->signal->stime); |
1da177e4c Linux-2.6.12-rc2 |
1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 |
info.si_status = tsk->exit_code & 0x7f; if (tsk->exit_code & 0x80) info.si_code = CLD_DUMPED; else if (tsk->exit_code & 0x7f) info.si_code = CLD_KILLED; else { info.si_code = CLD_EXITED; info.si_status = tsk->exit_code >> 8; } psig = tsk->parent->sighand; spin_lock_irqsave(&psig->siglock, flags); |
d21142ece ptrace: kill task... |
1614 |
if (!tsk->ptrace && sig == SIGCHLD && |
1da177e4c Linux-2.6.12-rc2 |
1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 |
(psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN || (psig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT))) { /* * We are exiting and our parent doesn't care. POSIX.1 * defines special semantics for setting SIGCHLD to SIG_IGN * or setting the SA_NOCLDWAIT flag: we should be reaped * automatically and not left for our parent's wait4 call. * Rather than having the parent do it as a magic kind of * signal handler, we just set this to tell do_exit that we * can be cleaned up without becoming a zombie. Note that * we still call __wake_up_parent in this case, because a * blocked sys_wait4 might now return -ECHILD. * * Whether we send SIGCHLD or not for SA_NOCLDWAIT * is implementation-defined: we do (if you don't want * it, just use SIG_IGN instead). */ |
53c8f9f19 make do_notify_pa... |
1632 |
autoreap = true; |
1da177e4c Linux-2.6.12-rc2 |
1633 |
if (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) |
53c8f9f19 make do_notify_pa... |
1634 |
sig = 0; |
1da177e4c Linux-2.6.12-rc2 |
1635 |
} |
53c8f9f19 make do_notify_pa... |
1636 |
if (valid_signal(sig) && sig) |
1da177e4c Linux-2.6.12-rc2 |
1637 1638 1639 |
__group_send_sig_info(sig, &info, tsk->parent); __wake_up_parent(tsk, tsk->parent); spin_unlock_irqrestore(&psig->siglock, flags); |
2b2a1ff64 tracehook: death |
1640 |
|
53c8f9f19 make do_notify_pa... |
1641 |
return autoreap; |
1da177e4c Linux-2.6.12-rc2 |
1642 |
} |
75b95953a job control: Add ... |
1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 |
/** * do_notify_parent_cldstop - notify parent of stopped/continued state change * @tsk: task reporting the state change * @for_ptracer: the notification is for ptracer * @why: CLD_{CONTINUED|STOPPED|TRAPPED} to report * * Notify @tsk's parent that the stopped/continued state has changed. If * @for_ptracer is %false, @tsk's group leader notifies to its real parent. * If %true, @tsk reports to @tsk->parent which should be the ptracer. * * CONTEXT: * Must be called with tasklist_lock at least read locked. */ static void do_notify_parent_cldstop(struct task_struct *tsk, bool for_ptracer, int why) |
1da177e4c Linux-2.6.12-rc2 |
1658 1659 1660 |
{ struct siginfo info; unsigned long flags; |
bc505a478 [PATCH] do_notify... |
1661 |
struct task_struct *parent; |
1da177e4c Linux-2.6.12-rc2 |
1662 |
struct sighand_struct *sighand; |
6fac4829c cputime: Use acce... |
1663 |
cputime_t utime, stime; |
1da177e4c Linux-2.6.12-rc2 |
1664 |
|
75b95953a job control: Add ... |
1665 |
if (for_ptracer) { |
bc505a478 [PATCH] do_notify... |
1666 |
parent = tsk->parent; |
75b95953a job control: Add ... |
1667 |
} else { |
bc505a478 [PATCH] do_notify... |
1668 1669 1670 |
tsk = tsk->group_leader; parent = tsk->real_parent; } |
1da177e4c Linux-2.6.12-rc2 |
1671 1672 |
info.si_signo = SIGCHLD; info.si_errno = 0; |
b488893a3 pid namespaces: c... |
1673 |
/* |
5aba085ed kernel/signal.c: ... |
1674 |
* see comment in do_notify_parent() about the following 4 lines |
b488893a3 pid namespaces: c... |
1675 1676 |
*/ rcu_read_lock(); |
17cf22c33 pidns: Use task_a... |
1677 |
info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(parent)); |
54ba47eda userns: signal re... |
1678 |
info.si_uid = from_kuid_munged(task_cred_xxx(parent, user_ns), task_uid(tsk)); |
b488893a3 pid namespaces: c... |
1679 |
rcu_read_unlock(); |
6fac4829c cputime: Use acce... |
1680 1681 1682 |
task_cputime(tsk, &utime, &stime); info.si_utime = cputime_to_clock_t(utime); info.si_stime = cputime_to_clock_t(stime); |
1da177e4c Linux-2.6.12-rc2 |
1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 |
info.si_code = why; switch (why) { case CLD_CONTINUED: info.si_status = SIGCONT; break; case CLD_STOPPED: info.si_status = tsk->signal->group_exit_code & 0x7f; break; case CLD_TRAPPED: info.si_status = tsk->exit_code & 0x7f; break; default: BUG(); } sighand = parent->sighand; spin_lock_irqsave(&sighand->siglock, flags); if (sighand->action[SIGCHLD-1].sa.sa_handler != SIG_IGN && !(sighand->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDSTOP)) __group_send_sig_info(SIGCHLD, &info, parent); /* * Even if SIGCHLD is not generated, we must wake up wait4 calls. */ __wake_up_parent(tsk, parent); spin_unlock_irqrestore(&sighand->siglock, flags); } |
d5f70c00a [PATCH] coredump:... |
1710 1711 |
static inline int may_ptrace_stop(void) { |
d21142ece ptrace: kill task... |
1712 |
if (!likely(current->ptrace)) |
d5f70c00a [PATCH] coredump:... |
1713 |
return 0; |
d5f70c00a [PATCH] coredump:... |
1714 1715 1716 1717 1718 1719 |
/* * Are we in the middle of do_coredump? * If so and our tracer is also part of the coredump stopping * is a deadlock situation, and pointless because our tracer * is dead so don't allow us to stop. * If SIGKILL was already sent before the caller unlocked |
999d9fc16 coredump: move mm... |
1720 |
* ->siglock we must see ->core_state != NULL. Otherwise it |
d5f70c00a [PATCH] coredump:... |
1721 |
* is safe to enter schedule(). |
9899d11f6 ptrace: ensure ar... |
1722 1723 1724 1725 |
* * This is almost outdated, a task with the pending SIGKILL can't * block in TASK_TRACED. But PTRACE_EVENT_EXIT can be reported * after SIGKILL was already dequeued. |
d5f70c00a [PATCH] coredump:... |
1726 |
*/ |
999d9fc16 coredump: move mm... |
1727 |
if (unlikely(current->mm->core_state) && |
d5f70c00a [PATCH] coredump:... |
1728 1729 1730 1731 1732 |
unlikely(current->mm == current->parent->mm)) return 0; return 1; } |
1da177e4c Linux-2.6.12-rc2 |
1733 |
/* |
5aba085ed kernel/signal.c: ... |
1734 |
* Return non-zero if there is a SIGKILL that should be waking us up. |
1a669c2f1 Add arch_ptrace_stop |
1735 1736 1737 1738 |
* Called with the siglock held. */ static int sigkill_pending(struct task_struct *tsk) { |
3d749b9e6 ptrace: simplify ... |
1739 1740 |
return sigismember(&tsk->pending.signal, SIGKILL) || sigismember(&tsk->signal->shared_pending.signal, SIGKILL); |
1a669c2f1 Add arch_ptrace_stop |
1741 1742 1743 |
} /* |
1da177e4c Linux-2.6.12-rc2 |
1744 1745 1746 1747 1748 1749 1750 |
* This must be called with current->sighand->siglock held. * * This should be the path for all ptrace stops. * We always set current->last_siginfo while stopped here. * That makes it a way to test a stopped process for * being ptrace-stopped vs being job-control-stopped. * |
20686a309 ptrace_stop: fix ... |
1751 1752 |
* If we actually decide not to stop at all because the tracer * is gone, we keep current->exit_code unless clear_code. |
1da177e4c Linux-2.6.12-rc2 |
1753 |
*/ |
fe1bc6a09 ptrace: Add @why ... |
1754 |
static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info) |
b84011508 signals: annotate... |
1755 1756 |
__releases(¤t->sighand->siglock) __acquires(¤t->sighand->siglock) |
1da177e4c Linux-2.6.12-rc2 |
1757 |
{ |
ceb6bd67f job control: Noti... |
1758 |
bool gstop_done = false; |
1a669c2f1 Add arch_ptrace_stop |
1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 |
if (arch_ptrace_stop_needed(exit_code, info)) { /* * The arch code has something special to do before a * ptrace stop. This is allowed to block, e.g. for faults * on user stack pages. We can't keep the siglock while * calling arch_ptrace_stop, so we must release it now. * To preserve proper semantics, we must do this before * any signal bookkeeping like checking group_stop_count. * Meanwhile, a SIGKILL could come in before we retake the * siglock. That must prevent us from sleeping in TASK_TRACED. * So after regaining the lock, we must check for SIGKILL. */ spin_unlock_irq(¤t->sighand->siglock); arch_ptrace_stop(exit_code, info); spin_lock_irq(¤t->sighand->siglock); |
3d749b9e6 ptrace: simplify ... |
1774 1775 |
if (sigkill_pending(current)) return; |
1a669c2f1 Add arch_ptrace_stop |
1776 |
} |
1da177e4c Linux-2.6.12-rc2 |
1777 |
/* |
81be24b8c ptrace: relocate ... |
1778 1779 1780 1781 1782 |
* We're committing to trapping. TRACED should be visible before * TRAPPING is cleared; otherwise, the tracer might fail do_wait(). * Also, transition to TRACED and updates to ->jobctl should be * atomic with respect to siglock and should be done after the arch * hook as siglock is released and regrabbed across it. |
1da177e4c Linux-2.6.12-rc2 |
1783 |
*/ |
81be24b8c ptrace: relocate ... |
1784 |
set_current_state(TASK_TRACED); |
1da177e4c Linux-2.6.12-rc2 |
1785 1786 1787 |
current->last_siginfo = info; current->exit_code = exit_code; |
d79fdd6d9 ptrace: Clean tra... |
1788 |
/* |
0ae8ce1c8 ptrace: Participa... |
1789 1790 |
* If @why is CLD_STOPPED, we're trapping to participate in a group * stop. Do the bookkeeping. Note that if SIGCONT was delievered |
73ddff2be job control: intr... |
1791 1792 1793 |
* across siglock relocks since INTERRUPT was scheduled, PENDING * could be clear now. We act as if SIGCONT is received after * TASK_TRACED is entered - ignore it. |
d79fdd6d9 ptrace: Clean tra... |
1794 |
*/ |
a8f072c1d job control: rena... |
1795 |
if (why == CLD_STOPPED && (current->jobctl & JOBCTL_STOP_PENDING)) |
ceb6bd67f job control: Noti... |
1796 |
gstop_done = task_participate_group_stop(current); |
d79fdd6d9 ptrace: Clean tra... |
1797 |
|
fb1d910c1 ptrace: implement... |
1798 |
/* any trap clears pending STOP trap, STOP trap clears NOTIFY */ |
73ddff2be job control: intr... |
1799 |
task_clear_jobctl_pending(current, JOBCTL_TRAP_STOP); |
fb1d910c1 ptrace: implement... |
1800 1801 |
if (info && info->si_code >> 8 == PTRACE_EVENT_STOP) task_clear_jobctl_pending(current, JOBCTL_TRAP_NOTIFY); |
73ddff2be job control: intr... |
1802 |
|
81be24b8c ptrace: relocate ... |
1803 |
/* entering a trap, clear TRAPPING */ |
a8f072c1d job control: rena... |
1804 |
task_clear_jobctl_trapping(current); |
d79fdd6d9 ptrace: Clean tra... |
1805 |
|
1da177e4c Linux-2.6.12-rc2 |
1806 1807 |
spin_unlock_irq(¤t->sighand->siglock); read_lock(&tasklist_lock); |
3d749b9e6 ptrace: simplify ... |
1808 |
if (may_ptrace_stop()) { |
ceb6bd67f job control: Noti... |
1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 |
/* * Notify parents of the stop. * * While ptraced, there are two parents - the ptracer and * the real_parent of the group_leader. The ptracer should * know about every stop while the real parent is only * interested in the completion of group stop. The states * for the two don't interact with each other. Notify * separately unless they're gonna be duplicates. */ do_notify_parent_cldstop(current, true, why); |
bb3696da8 ptrace: kill real... |
1820 |
if (gstop_done && ptrace_reparented(current)) |
ceb6bd67f job control: Noti... |
1821 |
do_notify_parent_cldstop(current, false, why); |
53da1d945 fix ptrace slowness |
1822 1823 1824 1825 1826 1827 1828 |
/* * Don't want to allow preemption here, because * sys_ptrace() needs this task to be inactive. * * XXX: implement read_unlock_no_resched(). */ preempt_disable(); |
1da177e4c Linux-2.6.12-rc2 |
1829 |
read_unlock(&tasklist_lock); |
53da1d945 fix ptrace slowness |
1830 |
preempt_enable_no_resched(); |
5d8f72b55 freezer: change p... |
1831 |
freezable_schedule(); |
1da177e4c Linux-2.6.12-rc2 |
1832 1833 1834 |
} else { /* * By the time we got the lock, our tracer went away. |
6405f7f46 ptrace_stop: fix ... |
1835 |
* Don't drop the lock yet, another tracer may come. |
ceb6bd67f job control: Noti... |
1836 1837 1838 |
* * If @gstop_done, the ptracer went away between group stop * completion and here. During detach, it would have set |
a8f072c1d job control: rena... |
1839 1840 1841 |
* JOBCTL_STOP_PENDING on us and we'll re-enter * TASK_STOPPED in do_signal_stop() on return, so notifying * the real parent of the group stop completion is enough. |
1da177e4c Linux-2.6.12-rc2 |
1842 |
*/ |
ceb6bd67f job control: Noti... |
1843 1844 |
if (gstop_done) do_notify_parent_cldstop(current, false, why); |
9899d11f6 ptrace: ensure ar... |
1845 |
/* tasklist protects us from ptrace_freeze_traced() */ |
6405f7f46 ptrace_stop: fix ... |
1846 |
__set_current_state(TASK_RUNNING); |
20686a309 ptrace_stop: fix ... |
1847 1848 |
if (clear_code) current->exit_code = 0; |
6405f7f46 ptrace_stop: fix ... |
1849 |
read_unlock(&tasklist_lock); |
1da177e4c Linux-2.6.12-rc2 |
1850 1851 1852 1853 1854 1855 1856 1857 1858 |
} /* * We are back. Now reacquire the siglock before touching * last_siginfo, so that we are sure to have synchronized with * any signal-sending on another CPU that wants to examine it. */ spin_lock_irq(¤t->sighand->siglock); current->last_siginfo = NULL; |
544b2c91a ptrace: implement... |
1859 1860 |
/* LISTENING can be set only during STOP traps, clear it */ current->jobctl &= ~JOBCTL_LISTENING; |
1da177e4c Linux-2.6.12-rc2 |
1861 1862 1863 |
/* * Queued signals ignored us while we were stopped for tracing. * So check for any that we should take before resuming user mode. |
b74d0deb9 Restrict clearing... |
1864 |
* This sets TIF_SIGPENDING, but never clears it. |
1da177e4c Linux-2.6.12-rc2 |
1865 |
*/ |
b74d0deb9 Restrict clearing... |
1866 |
recalc_sigpending_tsk(current); |
1da177e4c Linux-2.6.12-rc2 |
1867 |
} |
3544d72a0 ptrace: implement... |
1868 |
static void ptrace_do_notify(int signr, int exit_code, int why) |
1da177e4c Linux-2.6.12-rc2 |
1869 1870 |
{ siginfo_t info; |
1da177e4c Linux-2.6.12-rc2 |
1871 |
memset(&info, 0, sizeof info); |
3544d72a0 ptrace: implement... |
1872 |
info.si_signo = signr; |
1da177e4c Linux-2.6.12-rc2 |
1873 |
info.si_code = exit_code; |
b488893a3 pid namespaces: c... |
1874 |
info.si_pid = task_pid_vnr(current); |
078de5f70 userns: Store uid... |
1875 |
info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); |
1da177e4c Linux-2.6.12-rc2 |
1876 1877 |
/* Let the debugger run. */ |
3544d72a0 ptrace: implement... |
1878 1879 1880 1881 1882 1883 |
ptrace_stop(exit_code, why, 1, &info); } void ptrace_notify(int exit_code) { BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP); |
f784e8a79 task_work: Simpli... |
1884 1885 |
if (unlikely(current->task_works)) task_work_run(); |
3544d72a0 ptrace: implement... |
1886 |
|
1da177e4c Linux-2.6.12-rc2 |
1887 |
spin_lock_irq(¤t->sighand->siglock); |
3544d72a0 ptrace: implement... |
1888 |
ptrace_do_notify(SIGTRAP, exit_code, CLD_TRAPPED); |
1da177e4c Linux-2.6.12-rc2 |
1889 1890 |
spin_unlock_irq(¤t->sighand->siglock); } |
73ddff2be job control: intr... |
1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 |
/** * do_signal_stop - handle group stop for SIGSTOP and other stop signals * @signr: signr causing group stop if initiating * * If %JOBCTL_STOP_PENDING is not set yet, initiate group stop with @signr * and participate in it. If already set, participate in the existing * group stop. If participated in a group stop (and thus slept), %true is * returned with siglock released. * * If ptraced, this function doesn't handle stop itself. Instead, * %JOBCTL_TRAP_STOP is scheduled and %false is returned with siglock * untouched. The caller must ensure that INTERRUPT trap handling takes * places afterwards. * * CONTEXT: * Must be called with @current->sighand->siglock held, which is released * on %true return. * * RETURNS: * %false if group stop is already cancelled or ptrace trap is scheduled. * %true if participated in group stop. |
1da177e4c Linux-2.6.12-rc2 |
1912 |
*/ |
73ddff2be job control: intr... |
1913 1914 |
static bool do_signal_stop(int signr) __releases(¤t->sighand->siglock) |
1da177e4c Linux-2.6.12-rc2 |
1915 1916 |
{ struct signal_struct *sig = current->signal; |
1da177e4c Linux-2.6.12-rc2 |
1917 |
|
a8f072c1d job control: rena... |
1918 1919 |
if (!(current->jobctl & JOBCTL_STOP_PENDING)) { unsigned int gstop = JOBCTL_STOP_PENDING | JOBCTL_STOP_CONSUME; |
f558b7e40 remove handle_gro... |
1920 |
struct task_struct *t; |
a8f072c1d job control: rena... |
1921 1922 |
/* signr will be recorded in task->jobctl for retries */ WARN_ON_ONCE(signr & ~JOBCTL_STOP_SIGMASK); |
d79fdd6d9 ptrace: Clean tra... |
1923 |
|
a8f072c1d job control: rena... |
1924 |
if (!likely(current->jobctl & JOBCTL_STOP_DEQUEUED) || |
573cf9ad7 signals: do_signa... |
1925 |
unlikely(signal_group_exit(sig))) |
73ddff2be job control: intr... |
1926 |
return false; |
1da177e4c Linux-2.6.12-rc2 |
1927 |
/* |
408a37de6 job control: Don'... |
1928 1929 1930 1931 1932 1933 1934 |
* There is no group stop already in progress. We must * initiate one now. * * While ptraced, a task may be resumed while group stop is * still in effect and then receive a stop signal and * initiate another group stop. This deviates from the * usual behavior as two consecutive stop signals can't |
780006eac signal: do_signal... |
1935 1936 |
* cause two group stops when !ptraced. That is why we * also check !task_is_stopped(t) below. |
408a37de6 job control: Don'... |
1937 1938 1939 1940 1941 1942 1943 1944 |
* * The condition can be distinguished by testing whether * SIGNAL_STOP_STOPPED is already set. Don't generate * group_exit_code in such case. * * This is not necessary for SIGNAL_STOP_CONTINUED because * an intervening stop signal is required to cause two * continued events regardless of ptrace. |
1da177e4c Linux-2.6.12-rc2 |
1945 |
*/ |
408a37de6 job control: Don'... |
1946 1947 |
if (!(sig->flags & SIGNAL_STOP_STOPPED)) sig->group_exit_code = signr; |
1da177e4c Linux-2.6.12-rc2 |
1948 |
|
7dd3db54e job control: intr... |
1949 1950 1951 1952 |
sig->group_stop_count = 0; if (task_set_jobctl_pending(current, signr | gstop)) sig->group_stop_count++; |
1da177e4c Linux-2.6.12-rc2 |
1953 |
|
d79fdd6d9 ptrace: Clean tra... |
1954 1955 |
for (t = next_thread(current); t != current; t = next_thread(t)) { |
1da177e4c Linux-2.6.12-rc2 |
1956 |
/* |
a122b341b [PATCH] do_signal... |
1957 1958 1959 |
* Setting state to TASK_STOPPED for a group * stop is always done with the siglock held, * so this check has no races. |
1da177e4c Linux-2.6.12-rc2 |
1960 |
*/ |
7dd3db54e job control: intr... |
1961 1962 |
if (!task_is_stopped(t) && task_set_jobctl_pending(t, signr | gstop)) { |
ae6d2ed7b signals: tracehoo... |
1963 |
sig->group_stop_count++; |
fb1d910c1 ptrace: implement... |
1964 1965 1966 1967 |
if (likely(!(t->ptrace & PT_SEIZED))) signal_wake_up(t, 0); else ptrace_trap_notify(t); |
a122b341b [PATCH] do_signal... |
1968 |
} |
d79fdd6d9 ptrace: Clean tra... |
1969 |
} |
1da177e4c Linux-2.6.12-rc2 |
1970 |
} |
73ddff2be job control: intr... |
1971 |
|
d21142ece ptrace: kill task... |
1972 |
if (likely(!current->ptrace)) { |
5224fa366 ptrace: Make do_s... |
1973 |
int notify = 0; |
1da177e4c Linux-2.6.12-rc2 |
1974 |
|
5224fa366 ptrace: Make do_s... |
1975 1976 1977 1978 1979 1980 1981 |
/* * If there are no other threads in the group, or if there * is a group stop in progress and we are the last to stop, * report to the parent. */ if (task_participate_group_stop(current)) notify = CLD_STOPPED; |
ae6d2ed7b signals: tracehoo... |
1982 |
__set_current_state(TASK_STOPPED); |
5224fa366 ptrace: Make do_s... |
1983 |
spin_unlock_irq(¤t->sighand->siglock); |
62bcf9d99 job control: Job ... |
1984 1985 1986 1987 1988 1989 1990 1991 1992 |
/* * Notify the parent of the group stop completion. Because * we're not holding either the siglock or tasklist_lock * here, ptracer may attach inbetween; however, this is for * group stop and should always be delivered to the real * parent of the group leader. The new ptracer will get * its notification when this task transitions into * TASK_TRACED. */ |
5224fa366 ptrace: Make do_s... |
1993 1994 |
if (notify) { read_lock(&tasklist_lock); |
62bcf9d99 job control: Job ... |
1995 |
do_notify_parent_cldstop(current, false, notify); |
5224fa366 ptrace: Make do_s... |
1996 1997 1998 1999 |
read_unlock(&tasklist_lock); } /* Now we don't run again until woken by SIGCONT or SIGKILL */ |
5d8f72b55 freezer: change p... |
2000 |
freezable_schedule(); |
73ddff2be job control: intr... |
2001 |
return true; |
d79fdd6d9 ptrace: Clean tra... |
2002 |
} else { |
73ddff2be job control: intr... |
2003 2004 2005 2006 2007 2008 |
/* * While ptraced, group stop is handled by STOP trap. * Schedule it and let the caller deal with it. */ task_set_jobctl_pending(current, JOBCTL_TRAP_STOP); return false; |
ae6d2ed7b signals: tracehoo... |
2009 |
} |
73ddff2be job control: intr... |
2010 |
} |
1da177e4c Linux-2.6.12-rc2 |
2011 |
|
73ddff2be job control: intr... |
2012 2013 2014 |
/** * do_jobctl_trap - take care of ptrace jobctl traps * |
3544d72a0 ptrace: implement... |
2015 2016 2017 2018 2019 2020 2021 |
* When PT_SEIZED, it's used for both group stop and explicit * SEIZE/INTERRUPT traps. Both generate PTRACE_EVENT_STOP trap with * accompanying siginfo. If stopped, lower eight bits of exit_code contain * the stop signal; otherwise, %SIGTRAP. * * When !PT_SEIZED, it's used only for group stop trap with stop signal * number as exit_code and no siginfo. |
73ddff2be job control: intr... |
2022 2023 2024 2025 2026 2027 2028 |
* * CONTEXT: * Must be called with @current->sighand->siglock held, which may be * released and re-acquired before returning with intervening sleep. */ static void do_jobctl_trap(void) { |
3544d72a0 ptrace: implement... |
2029 |
struct signal_struct *signal = current->signal; |
73ddff2be job control: intr... |
2030 |
int signr = current->jobctl & JOBCTL_STOP_SIGMASK; |
ae6d2ed7b signals: tracehoo... |
2031 |
|
3544d72a0 ptrace: implement... |
2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 |
if (current->ptrace & PT_SEIZED) { if (!signal->group_stop_count && !(signal->flags & SIGNAL_STOP_STOPPED)) signr = SIGTRAP; WARN_ON_ONCE(!signr); ptrace_do_notify(signr, signr | (PTRACE_EVENT_STOP << 8), CLD_STOPPED); } else { WARN_ON_ONCE(!signr); ptrace_stop(signr, CLD_STOPPED, 0, NULL); current->exit_code = 0; |
ae6d2ed7b signals: tracehoo... |
2043 |
} |
1da177e4c Linux-2.6.12-rc2 |
2044 |
} |
94eb22d50 ptrace_signal(): ... |
2045 |
static int ptrace_signal(int signr, siginfo_t *info) |
18c98b652 ptrace_signal sub... |
2046 |
{ |
b7f9591c4 get rid of ptrace... |
2047 |
ptrace_signal_deliver(); |
8a3524180 ptrace: fix ptrac... |
2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 |
/* * We do not check sig_kernel_stop(signr) but set this marker * unconditionally because we do not know whether debugger will * change signr. This flag has no meaning unless we are going * to stop after return from ptrace_stop(). In this case it will * be checked in do_signal_stop(), we should only stop if it was * not cleared by SIGCONT while we were sleeping. See also the * comment in dequeue_signal(). */ current->jobctl |= JOBCTL_STOP_DEQUEUED; |
fe1bc6a09 ptrace: Add @why ... |
2058 |
ptrace_stop(signr, CLD_TRAPPED, 0, info); |
18c98b652 ptrace_signal sub... |
2059 2060 2061 2062 2063 2064 2065 |
/* We're back. Did the debugger cancel the sig? */ signr = current->exit_code; if (signr == 0) return signr; current->exit_code = 0; |
5aba085ed kernel/signal.c: ... |
2066 2067 2068 2069 2070 2071 |
/* * Update the siginfo structure if the signal has * changed. If the debugger wanted something * specific in the siginfo structure then it should * have updated *info via PTRACE_SETSIGINFO. */ |
18c98b652 ptrace_signal sub... |
2072 2073 2074 2075 |
if (signr != info->si_signo) { info->si_signo = signr; info->si_errno = 0; info->si_code = SI_USER; |
6b550f949 user namespace: m... |
2076 |
rcu_read_lock(); |
18c98b652 ptrace_signal sub... |
2077 |
info->si_pid = task_pid_vnr(current->parent); |
54ba47eda userns: signal re... |
2078 2079 |
info->si_uid = from_kuid_munged(current_user_ns(), task_uid(current->parent)); |
6b550f949 user namespace: m... |
2080 |
rcu_read_unlock(); |
18c98b652 ptrace_signal sub... |
2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 |
} /* If the (new) signal is now blocked, requeue it. */ if (sigismember(¤t->blocked, signr)) { specific_send_sig_info(signr, info, current); signr = 0; } return signr; } |
1da177e4c Linux-2.6.12-rc2 |
2091 2092 2093 |
int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie) { |
f6b76d4fb get_signal_to_del... |
2094 2095 2096 |
struct sighand_struct *sighand = current->sighand; struct signal_struct *signal = current->signal; int signr; |
1da177e4c Linux-2.6.12-rc2 |
2097 |
|
f784e8a79 task_work: Simpli... |
2098 2099 |
if (unlikely(current->task_works)) task_work_run(); |
726670280 signal: make sure... |
2100 |
|
0326f5a94 uprobes/core: Han... |
2101 2102 |
if (unlikely(uprobe_deny_signal())) return 0; |
13b1c3d4b freezer vs stoppe... |
2103 |
/* |
5d8f72b55 freezer: change p... |
2104 2105 2106 |
* Do this once, we can't return to user-mode if freezing() == T. * do_signal_stop() and ptrace_stop() do freezable_schedule() and * thus do not need another check after return. |
13b1c3d4b freezer vs stoppe... |
2107 |
*/ |
fc558a749 [PATCH] swsusp: f... |
2108 |
try_to_freeze(); |
5d8f72b55 freezer: change p... |
2109 |
relock: |
f6b76d4fb get_signal_to_del... |
2110 |
spin_lock_irq(&sighand->siglock); |
021e1ae3d signals: document... |
2111 2112 2113 2114 2115 |
/* * Every stopped thread goes here after wakeup. Check to see if * we should notify the parent, prepare_signal(SIGCONT) encodes * the CLD_ si_code into SIGNAL_CLD_MASK bits. */ |
f6b76d4fb get_signal_to_del... |
2116 |
if (unlikely(signal->flags & SIGNAL_CLD_MASK)) { |
c672af35d signal: Fix SIGCO... |
2117 2118 2119 2120 2121 2122 |
int why; if (signal->flags & SIGNAL_CLD_CONTINUED) why = CLD_CONTINUED; else why = CLD_STOPPED; |
f6b76d4fb get_signal_to_del... |
2123 |
signal->flags &= ~SIGNAL_CLD_MASK; |
e44205519 signals: re-assig... |
2124 |
|
ae6d2ed7b signals: tracehoo... |
2125 |
spin_unlock_irq(&sighand->siglock); |
fa00b80b3 tracehook: job co... |
2126 |
|
ceb6bd67f job control: Noti... |
2127 2128 2129 2130 2131 2132 2133 2134 |
/* * Notify the parent that we're continuing. This event is * always per-process and doesn't make whole lot of sense * for ptracers, who shouldn't consume the state via * wait(2) either, but, for backward compatibility, notify * the ptracer of the group leader too unless it's gonna be * a duplicate. */ |
edf2ed153 ptrace: Kill trac... |
2135 |
read_lock(&tasklist_lock); |
ceb6bd67f job control: Noti... |
2136 |
do_notify_parent_cldstop(current, false, why); |
bb3696da8 ptrace: kill real... |
2137 2138 2139 |
if (ptrace_reparented(current->group_leader)) do_notify_parent_cldstop(current->group_leader, true, why); |
edf2ed153 ptrace: Kill trac... |
2140 |
read_unlock(&tasklist_lock); |
ceb6bd67f job control: Noti... |
2141 |
|
e44205519 signals: re-assig... |
2142 2143 |
goto relock; } |
1da177e4c Linux-2.6.12-rc2 |
2144 2145 |
for (;;) { struct k_sigaction *ka; |
1be53963b signals: check ->... |
2146 |
|
dd1d67726 signal: remove th... |
2147 2148 |
if (unlikely(current->jobctl & JOBCTL_STOP_PENDING) && do_signal_stop(0)) |
7bcf6a2ca tracehook: get_si... |
2149 |
goto relock; |
1be53963b signals: check ->... |
2150 |
|
73ddff2be job control: intr... |
2151 2152 2153 2154 2155 |
if (unlikely(current->jobctl & JOBCTL_TRAP_MASK)) { do_jobctl_trap(); spin_unlock_irq(&sighand->siglock); goto relock; } |
1da177e4c Linux-2.6.12-rc2 |
2156 |
|
dd1d67726 signal: remove th... |
2157 |
signr = dequeue_signal(current, ¤t->blocked, info); |
7bcf6a2ca tracehook: get_si... |
2158 |
|
dd1d67726 signal: remove th... |
2159 2160 |
if (!signr) break; /* will return 0 */ |
7bcf6a2ca tracehook: get_si... |
2161 |
|
8a3524180 ptrace: fix ptrac... |
2162 |
if (unlikely(current->ptrace) && signr != SIGKILL) { |
94eb22d50 ptrace_signal(): ... |
2163 |
signr = ptrace_signal(signr, info); |
dd1d67726 signal: remove th... |
2164 2165 |
if (!signr) continue; |
1da177e4c Linux-2.6.12-rc2 |
2166 |
} |
dd1d67726 signal: remove th... |
2167 |
ka = &sighand->action[signr-1]; |
f9d4257e0 tracepoint: Add s... |
2168 2169 |
/* Trace actually delivered signals. */ trace_signal_deliver(signr, info, ka); |
1da177e4c Linux-2.6.12-rc2 |
2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 |
if (ka->sa.sa_handler == SIG_IGN) /* Do nothing. */ continue; if (ka->sa.sa_handler != SIG_DFL) { /* Run the handler. */ *return_ka = *ka; if (ka->sa.sa_flags & SA_ONESHOT) ka->sa.sa_handler = SIG_DFL; break; /* will return non-zero "signr" value */ } /* * Now we are doing the default action for this signal. */ if (sig_kernel_ignore(signr)) /* Default is nothing. */ continue; |
84d737866 [PATCH] add child... |
2187 |
/* |
0fbc26a6c pid namespaces: a... |
2188 |
* Global init gets no signals it doesn't want. |
b3bfa0cba signals: protect ... |
2189 2190 2191 2192 2193 2194 2195 |
* Container-init gets no signals it doesn't want from same * container. * * Note that if global/container-init sees a sig_kernel_only() * signal here, the signal must have been generated internally * or must have come from an ancestor namespace. In either * case, the signal cannot be dropped. |
84d737866 [PATCH] add child... |
2196 |
*/ |
fae5fa44f signals: fix /sbi... |
2197 |
if (unlikely(signal->flags & SIGNAL_UNKILLABLE) && |
b3bfa0cba signals: protect ... |
2198 |
!sig_kernel_only(signr)) |
1da177e4c Linux-2.6.12-rc2 |
2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 |
continue; if (sig_kernel_stop(signr)) { /* * The default action is to stop all threads in * the thread group. The job control signals * do nothing in an orphaned pgrp, but SIGSTOP * always works. Note that siglock needs to be * dropped during the call to is_orphaned_pgrp() * because of lock ordering with tasklist_lock. * This allows an intervening SIGCONT to be posted. * We need to check for that and bail out if necessary. */ if (signr != SIGSTOP) { |
f6b76d4fb get_signal_to_del... |
2213 |
spin_unlock_irq(&sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2214 2215 |
/* signals can be posted during this window */ |
3e7cd6c41 [PATCH] pid: repl... |
2216 |
if (is_current_pgrp_orphaned()) |
1da177e4c Linux-2.6.12-rc2 |
2217 |
goto relock; |
f6b76d4fb get_signal_to_del... |
2218 |
spin_lock_irq(&sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2219 |
} |
7bcf6a2ca tracehook: get_si... |
2220 |
if (likely(do_signal_stop(info->si_signo))) { |
1da177e4c Linux-2.6.12-rc2 |
2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 |
/* It released the siglock. */ goto relock; } /* * We didn't actually stop, due to a race * with SIGCONT or something like that. */ continue; } |
f6b76d4fb get_signal_to_del... |
2231 |
spin_unlock_irq(&sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2232 2233 2234 2235 2236 |
/* * Anything else is fatal, maybe with a core dump. */ current->flags |= PF_SIGNALED; |
2dce81bff signals: cleanup ... |
2237 |
|
1da177e4c Linux-2.6.12-rc2 |
2238 |
if (sig_kernel_coredump(signr)) { |
2dce81bff signals: cleanup ... |
2239 |
if (print_fatal_signals) |
4aaefee58 print_fatal_signa... |
2240 |
print_fatal_signal(info->si_signo); |
1da177e4c Linux-2.6.12-rc2 |
2241 2242 2243 2244 2245 2246 2247 2248 |
/* * If it was able to dump core, this kills all * other threads in the group and synchronizes with * their demise. If we lost the race with another * thread getting here, it set group_exit_code * first and our do_group_exit call below will use * that value and ignore the one we pass it. */ |
541880d9a do_coredump(): ge... |
2249 |
do_coredump(info); |
1da177e4c Linux-2.6.12-rc2 |
2250 2251 2252 2253 2254 |
} /* * Death signals, no core dump. */ |
7bcf6a2ca tracehook: get_si... |
2255 |
do_group_exit(info->si_signo); |
1da177e4c Linux-2.6.12-rc2 |
2256 2257 |
/* NOTREACHED */ } |
f6b76d4fb get_signal_to_del... |
2258 |
spin_unlock_irq(&sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2259 2260 |
return signr; } |
5e6292c0f signal: add block... |
2261 |
/** |
efee984c2 new helper: signa... |
2262 2263 2264 2265 2266 2267 |
* signal_delivered - * @sig: number of signal being delivered * @info: siginfo_t of signal being delivered * @ka: sigaction setting that chose the handler * @regs: user register state * @stepping: nonzero if debugger single-step or block-step in use |
5e6292c0f signal: add block... |
2268 2269 |
* * This function should be called when a signal has succesfully been |
efee984c2 new helper: signa... |
2270 2271 2272 |
* delivered. It updates the blocked signals accordingly (@ka->sa.sa_mask * is always blocked, and the signal itself is blocked unless %SA_NODEFER * is set in @ka->sa.sa_flags. Tracing is notified. |
5e6292c0f signal: add block... |
2273 |
*/ |
efee984c2 new helper: signa... |
2274 2275 |
void signal_delivered(int sig, siginfo_t *info, struct k_sigaction *ka, struct pt_regs *regs, int stepping) |
5e6292c0f signal: add block... |
2276 2277 |
{ sigset_t blocked; |
a610d6e67 pull clearing RES... |
2278 2279 2280 2281 2282 |
/* A signal was successfully delivered, and the saved sigmask was stored on the signal frame, and will be restored by sigreturn. So we can simply clear the restore sigmask flag. */ clear_restore_sigmask(); |
5e6292c0f signal: add block... |
2283 2284 |
sigorsets(&blocked, ¤t->blocked, &ka->sa.sa_mask); if (!(ka->sa.sa_flags & SA_NODEFER)) |
efee984c2 new helper: signa... |
2285 |
sigaddset(&blocked, sig); |
5e6292c0f signal: add block... |
2286 |
set_current_blocked(&blocked); |
efee984c2 new helper: signa... |
2287 |
tracehook_signal_handler(sig, info, ka, regs, stepping); |
5e6292c0f signal: add block... |
2288 |
} |
2ce5da175 new helper: signa... |
2289 2290 2291 2292 2293 2294 2295 2296 |
void signal_setup_done(int failed, struct ksignal *ksig, int stepping) { if (failed) force_sigsegv(ksig->sig, current); else signal_delivered(ksig->sig, &ksig->info, &ksig->ka, signal_pt_regs(), stepping); } |
0edceb7bc signal: introduce... |
2297 2298 |
/* * It could be that complete_signal() picked us to notify about the |
fec9993db signal: retarget_... |
2299 2300 |
* group-wide signal. Other threads should be notified now to take * the shared signals in @which since we will not. |
0edceb7bc signal: introduce... |
2301 |
*/ |
f646e227b signal: retarget_... |
2302 |
static void retarget_shared_pending(struct task_struct *tsk, sigset_t *which) |
0edceb7bc signal: introduce... |
2303 |
{ |
f646e227b signal: retarget_... |
2304 |
sigset_t retarget; |
0edceb7bc signal: introduce... |
2305 |
struct task_struct *t; |
f646e227b signal: retarget_... |
2306 2307 2308 |
sigandsets(&retarget, &tsk->signal->shared_pending.signal, which); if (sigisemptyset(&retarget)) return; |
0edceb7bc signal: introduce... |
2309 2310 |
t = tsk; while_each_thread(tsk, t) { |
fec9993db signal: retarget_... |
2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 |
if (t->flags & PF_EXITING) continue; if (!has_pending_signals(&retarget, &t->blocked)) continue; /* Remove the signals this thread can handle. */ sigandsets(&retarget, &retarget, &t->blocked); if (!signal_pending(t)) signal_wake_up(t, 0); if (sigisemptyset(&retarget)) break; |
0edceb7bc signal: introduce... |
2324 2325 |
} } |
d12619b5f fix group stop wi... |
2326 2327 2328 |
void exit_signals(struct task_struct *tsk) { int group_stop = 0; |
f646e227b signal: retarget_... |
2329 |
sigset_t unblocked; |
d12619b5f fix group stop wi... |
2330 |
|
77e4ef99d threadgroup: exte... |
2331 2332 2333 2334 2335 |
/* * @tsk is about to have PF_EXITING set - lock out users which * expect stable threadgroup. */ threadgroup_change_begin(tsk); |
5dee1707d move the related ... |
2336 2337 |
if (thread_group_empty(tsk) || signal_group_exit(tsk->signal)) { tsk->flags |= PF_EXITING; |
77e4ef99d threadgroup: exte... |
2338 |
threadgroup_change_end(tsk); |
5dee1707d move the related ... |
2339 |
return; |
d12619b5f fix group stop wi... |
2340 |
} |
5dee1707d move the related ... |
2341 |
spin_lock_irq(&tsk->sighand->siglock); |
d12619b5f fix group stop wi... |
2342 2343 2344 2345 2346 |
/* * From now this task is not visible for group-wide signals, * see wants_signal(), do_signal_stop(). */ tsk->flags |= PF_EXITING; |
77e4ef99d threadgroup: exte... |
2347 2348 |
threadgroup_change_end(tsk); |
5dee1707d move the related ... |
2349 2350 |
if (!signal_pending(tsk)) goto out; |
f646e227b signal: retarget_... |
2351 2352 2353 |
unblocked = tsk->blocked; signotset(&unblocked); retarget_shared_pending(tsk, &unblocked); |
5dee1707d move the related ... |
2354 |
|
a8f072c1d job control: rena... |
2355 |
if (unlikely(tsk->jobctl & JOBCTL_STOP_PENDING) && |
e5c1902e9 signal: Fix prema... |
2356 |
task_participate_group_stop(tsk)) |
edf2ed153 ptrace: Kill trac... |
2357 |
group_stop = CLD_STOPPED; |
5dee1707d move the related ... |
2358 |
out: |
d12619b5f fix group stop wi... |
2359 |
spin_unlock_irq(&tsk->sighand->siglock); |
62bcf9d99 job control: Job ... |
2360 2361 2362 2363 |
/* * If group stop has completed, deliver the notification. This * should always go to the real parent of the group leader. */ |
ae6d2ed7b signals: tracehoo... |
2364 |
if (unlikely(group_stop)) { |
d12619b5f fix group stop wi... |
2365 |
read_lock(&tasklist_lock); |
62bcf9d99 job control: Job ... |
2366 |
do_notify_parent_cldstop(tsk, false, group_stop); |
d12619b5f fix group stop wi... |
2367 2368 2369 |
read_unlock(&tasklist_lock); } } |
1da177e4c Linux-2.6.12-rc2 |
2370 2371 2372 2373 |
EXPORT_SYMBOL(recalc_sigpending); EXPORT_SYMBOL_GPL(dequeue_signal); EXPORT_SYMBOL(flush_signals); EXPORT_SYMBOL(force_sig); |
1da177e4c Linux-2.6.12-rc2 |
2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 |
EXPORT_SYMBOL(send_sig); EXPORT_SYMBOL(send_sig_info); EXPORT_SYMBOL(sigprocmask); EXPORT_SYMBOL(block_all_signals); EXPORT_SYMBOL(unblock_all_signals); /* * System call entry points. */ |
41c57892a kernel/signal.c: ... |
2384 2385 2386 |
/** * sys_restart_syscall - restart a system call */ |
754fe8d29 [CVE-2009-0029] S... |
2387 |
SYSCALL_DEFINE0(restart_syscall) |
1da177e4c Linux-2.6.12-rc2 |
2388 2389 2390 2391 2392 2393 2394 2395 2396 |
{ struct restart_block *restart = ¤t_thread_info()->restart_block; return restart->fn(restart); } long do_no_restart_syscall(struct restart_block *param) { return -EINTR; } |
b182801ab signal: do_sigtim... |
2397 2398 2399 2400 2401 |
static void __set_task_blocked(struct task_struct *tsk, const sigset_t *newset) { if (signal_pending(tsk) && !thread_group_empty(tsk)) { sigset_t newblocked; /* A set of now blocked but previously unblocked signals. */ |
702a5073f signal: rename si... |
2402 |
sigandnsets(&newblocked, newset, ¤t->blocked); |
b182801ab signal: do_sigtim... |
2403 2404 2405 2406 2407 |
retarget_shared_pending(tsk, &newblocked); } tsk->blocked = *newset; recalc_sigpending(); } |
e6fa16ab9 signal: sigprocma... |
2408 2409 2410 2411 2412 2413 |
/** * set_current_blocked - change current->blocked mask * @newset: new mask * * It is wrong to change ->blocked directly, this helper should be used * to ensure the process can't miss a shared signal we are going to block. |
1da177e4c Linux-2.6.12-rc2 |
2414 |
*/ |
77097ae50 most of set_curre... |
2415 2416 |
void set_current_blocked(sigset_t *newset) { |
77097ae50 most of set_curre... |
2417 |
sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP)); |
0c4a84234 signals: set_curr... |
2418 |
__set_current_blocked(newset); |
77097ae50 most of set_curre... |
2419 2420 2421 |
} void __set_current_blocked(const sigset_t *newset) |
e6fa16ab9 signal: sigprocma... |
2422 2423 2424 2425 |
{ struct task_struct *tsk = current; spin_lock_irq(&tsk->sighand->siglock); |
b182801ab signal: do_sigtim... |
2426 |
__set_task_blocked(tsk, newset); |
e6fa16ab9 signal: sigprocma... |
2427 2428 |
spin_unlock_irq(&tsk->sighand->siglock); } |
1da177e4c Linux-2.6.12-rc2 |
2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 |
/* * This is also useful for kernel threads that want to temporarily * (or permanently) block certain signals. * * NOTE! Unlike the user-mode sys_sigprocmask(), the kernel * interface happily blocks "unblockable" signals like SIGKILL * and friends. */ int sigprocmask(int how, sigset_t *set, sigset_t *oldset) { |
73ef4aeb6 signal: sigprocma... |
2440 2441 |
struct task_struct *tsk = current; sigset_t newset; |
1da177e4c Linux-2.6.12-rc2 |
2442 |
|
73ef4aeb6 signal: sigprocma... |
2443 |
/* Lockless, only current can change ->blocked, never from irq */ |
a26fd335b [PATCH] sigprocma... |
2444 |
if (oldset) |
73ef4aeb6 signal: sigprocma... |
2445 |
*oldset = tsk->blocked; |
a26fd335b [PATCH] sigprocma... |
2446 |
|
1da177e4c Linux-2.6.12-rc2 |
2447 2448 |
switch (how) { case SIG_BLOCK: |
73ef4aeb6 signal: sigprocma... |
2449 |
sigorsets(&newset, &tsk->blocked, set); |
1da177e4c Linux-2.6.12-rc2 |
2450 2451 |
break; case SIG_UNBLOCK: |
702a5073f signal: rename si... |
2452 |
sigandnsets(&newset, &tsk->blocked, set); |
1da177e4c Linux-2.6.12-rc2 |
2453 2454 |
break; case SIG_SETMASK: |
73ef4aeb6 signal: sigprocma... |
2455 |
newset = *set; |
1da177e4c Linux-2.6.12-rc2 |
2456 2457 |
break; default: |
73ef4aeb6 signal: sigprocma... |
2458 |
return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
2459 |
} |
a26fd335b [PATCH] sigprocma... |
2460 |
|
77097ae50 most of set_curre... |
2461 |
__set_current_blocked(&newset); |
73ef4aeb6 signal: sigprocma... |
2462 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
2463 |
} |
41c57892a kernel/signal.c: ... |
2464 2465 2466 |
/** * sys_rt_sigprocmask - change the list of currently blocked signals * @how: whether to add, remove, or set signals |
ada9c9331 signal.c: fix ker... |
2467 |
* @nset: stores pending signals |
41c57892a kernel/signal.c: ... |
2468 2469 2470 |
* @oset: previous value of signal mask if non-null * @sigsetsize: size of sigset_t type */ |
bb7efee2c signal: cleanup s... |
2471 |
SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, nset, |
17da2bd90 [CVE-2009-0029] S... |
2472 |
sigset_t __user *, oset, size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2473 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2474 |
sigset_t old_set, new_set; |
bb7efee2c signal: cleanup s... |
2475 |
int error; |
1da177e4c Linux-2.6.12-rc2 |
2476 2477 2478 |
/* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) |
bb7efee2c signal: cleanup s... |
2479 |
return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
2480 |
|
bb7efee2c signal: cleanup s... |
2481 2482 2483 2484 2485 |
old_set = current->blocked; if (nset) { if (copy_from_user(&new_set, nset, sizeof(sigset_t))) return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2486 |
sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); |
bb7efee2c signal: cleanup s... |
2487 |
error = sigprocmask(how, &new_set, NULL); |
1da177e4c Linux-2.6.12-rc2 |
2488 |
if (error) |
bb7efee2c signal: cleanup s... |
2489 2490 |
return error; } |
1da177e4c Linux-2.6.12-rc2 |
2491 |
|
bb7efee2c signal: cleanup s... |
2492 2493 2494 |
if (oset) { if (copy_to_user(oset, &old_set, sizeof(sigset_t))) return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2495 |
} |
bb7efee2c signal: cleanup s... |
2496 2497 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
2498 |
} |
322a56cb1 generic compat_sy... |
2499 |
#ifdef CONFIG_COMPAT |
322a56cb1 generic compat_sy... |
2500 2501 |
COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, compat_sigset_t __user *, oset, compat_size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2502 |
{ |
322a56cb1 generic compat_sy... |
2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 |
#ifdef __BIG_ENDIAN sigset_t old_set = current->blocked; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; if (nset) { compat_sigset_t new32; sigset_t new_set; int error; if (copy_from_user(&new32, nset, sizeof(compat_sigset_t))) return -EFAULT; sigset_from_compat(&new_set, &new32); sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); error = sigprocmask(how, &new_set, NULL); if (error) return error; } if (oset) { compat_sigset_t old32; sigset_to_compat(&old32, &old_set); |
db61ec29f fix compat_sys_rt... |
2527 |
if (copy_to_user(oset, &old32, sizeof(compat_sigset_t))) |
322a56cb1 generic compat_sy... |
2528 2529 2530 2531 2532 2533 2534 2535 2536 |
return -EFAULT; } return 0; #else return sys_rt_sigprocmask(how, (sigset_t __user *)nset, (sigset_t __user *)oset, sigsetsize); #endif } #endif |
1da177e4c Linux-2.6.12-rc2 |
2537 |
|
fe9c1db2c generic compat_sy... |
2538 |
static int do_sigpending(void *set, unsigned long sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2539 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2540 |
if (sigsetsize > sizeof(sigset_t)) |
fe9c1db2c generic compat_sy... |
2541 |
return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
2542 2543 |
spin_lock_irq(¤t->sighand->siglock); |
fe9c1db2c generic compat_sy... |
2544 |
sigorsets(set, ¤t->pending.signal, |
1da177e4c Linux-2.6.12-rc2 |
2545 2546 2547 2548 |
¤t->signal->shared_pending.signal); spin_unlock_irq(¤t->sighand->siglock); /* Outside the lock because only this thread touches it. */ |
fe9c1db2c generic compat_sy... |
2549 2550 |
sigandsets(set, ¤t->blocked, set); return 0; |
5aba085ed kernel/signal.c: ... |
2551 |
} |
1da177e4c Linux-2.6.12-rc2 |
2552 |
|
41c57892a kernel/signal.c: ... |
2553 2554 2555 |
/** * sys_rt_sigpending - examine a pending signal that has been raised * while blocked |
20f22ab42 signals: fix new ... |
2556 |
* @uset: stores pending signals |
41c57892a kernel/signal.c: ... |
2557 2558 |
* @sigsetsize: size of sigset_t type or larger */ |
fe9c1db2c generic compat_sy... |
2559 |
SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2560 |
{ |
fe9c1db2c generic compat_sy... |
2561 2562 2563 2564 2565 2566 2567 2568 |
sigset_t set; int err = do_sigpending(&set, sigsetsize); if (!err && copy_to_user(uset, &set, sigsetsize)) err = -EFAULT; return err; } #ifdef CONFIG_COMPAT |
fe9c1db2c generic compat_sy... |
2569 2570 |
COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset, compat_size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2571 |
{ |
fe9c1db2c generic compat_sy... |
2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 |
#ifdef __BIG_ENDIAN sigset_t set; int err = do_sigpending(&set, sigsetsize); if (!err) { compat_sigset_t set32; sigset_to_compat(&set32, &set); /* we can get here only if sigsetsize <= sizeof(set) */ if (copy_to_user(uset, &set32, sigsetsize)) err = -EFAULT; } return err; #else return sys_rt_sigpending((sigset_t __user *)uset, sigsetsize); #endif |
1da177e4c Linux-2.6.12-rc2 |
2586 |
} |
fe9c1db2c generic compat_sy... |
2587 |
#endif |
1da177e4c Linux-2.6.12-rc2 |
2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 |
#ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER int copy_siginfo_to_user(siginfo_t __user *to, siginfo_t *from) { int err; if (!access_ok (VERIFY_WRITE, to, sizeof(siginfo_t))) return -EFAULT; if (from->si_code < 0) return __copy_to_user(to, from, sizeof(siginfo_t)) ? -EFAULT : 0; /* * If you change siginfo_t structure, please be sure * this code is fixed accordingly. |
fba2afaae signal/timer/even... |
2603 2604 |
* Please remember to update the signalfd_copyinfo() function * inside fs/signalfd.c too, in case siginfo_t changes. |
1da177e4c Linux-2.6.12-rc2 |
2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 |
* It should never copy any pad contained in the structure * to avoid security leaks, but must copy the generic * 3 ints plus the relevant union member. */ err = __put_user(from->si_signo, &to->si_signo); err |= __put_user(from->si_errno, &to->si_errno); err |= __put_user((short)from->si_code, &to->si_code); switch (from->si_code & __SI_MASK) { case __SI_KILL: err |= __put_user(from->si_pid, &to->si_pid); err |= __put_user(from->si_uid, &to->si_uid); break; case __SI_TIMER: err |= __put_user(from->si_tid, &to->si_tid); err |= __put_user(from->si_overrun, &to->si_overrun); err |= __put_user(from->si_ptr, &to->si_ptr); break; case __SI_POLL: err |= __put_user(from->si_band, &to->si_band); err |= __put_user(from->si_fd, &to->si_fd); break; case __SI_FAULT: err |= __put_user(from->si_addr, &to->si_addr); #ifdef __ARCH_SI_TRAPNO err |= __put_user(from->si_trapno, &to->si_trapno); #endif |
a337fdac7 HWPOISON: Copy si... |
2631 |
#ifdef BUS_MCEERR_AO |
5aba085ed kernel/signal.c: ... |
2632 |
/* |
a337fdac7 HWPOISON: Copy si... |
2633 |
* Other callers might not initialize the si_lsb field, |
5aba085ed kernel/signal.c: ... |
2634 |
* so check explicitly for the right codes here. |
a337fdac7 HWPOISON: Copy si... |
2635 2636 2637 2638 |
*/ if (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO) err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); #endif |
1da177e4c Linux-2.6.12-rc2 |
2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 |
break; case __SI_CHLD: err |= __put_user(from->si_pid, &to->si_pid); err |= __put_user(from->si_uid, &to->si_uid); err |= __put_user(from->si_status, &to->si_status); err |= __put_user(from->si_utime, &to->si_utime); err |= __put_user(from->si_stime, &to->si_stime); break; case __SI_RT: /* This is not generated by the kernel as of now. */ case __SI_MESGQ: /* But this is */ err |= __put_user(from->si_pid, &to->si_pid); err |= __put_user(from->si_uid, &to->si_uid); err |= __put_user(from->si_ptr, &to->si_ptr); break; |
a0727e8ce signal, x86: add ... |
2653 2654 2655 2656 2657 2658 2659 |
#ifdef __ARCH_SIGSYS case __SI_SYS: err |= __put_user(from->si_call_addr, &to->si_call_addr); err |= __put_user(from->si_syscall, &to->si_syscall); err |= __put_user(from->si_arch, &to->si_arch); break; #endif |
1da177e4c Linux-2.6.12-rc2 |
2660 2661 2662 2663 2664 2665 2666 2667 2668 |
default: /* this is just in case for now ... */ err |= __put_user(from->si_pid, &to->si_pid); err |= __put_user(from->si_uid, &to->si_uid); break; } return err; } #endif |
41c57892a kernel/signal.c: ... |
2669 |
/** |
943df1485 signal: introduce... |
2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 |
* do_sigtimedwait - wait for queued signals specified in @which * @which: queued signals to wait for * @info: if non-null, the signal's siginfo is returned here * @ts: upper bound on process time suspension */ int do_sigtimedwait(const sigset_t *which, siginfo_t *info, const struct timespec *ts) { struct task_struct *tsk = current; long timeout = MAX_SCHEDULE_TIMEOUT; sigset_t mask = *which; int sig; if (ts) { if (!timespec_valid(ts)) return -EINVAL; timeout = timespec_to_jiffies(ts); /* * We can be close to the next tick, add another one * to ensure we will wait at least the time asked for. */ if (ts->tv_sec || ts->tv_nsec) timeout++; } /* * Invert the set of allowed signals to get those we want to block. */ sigdelsetmask(&mask, sigmask(SIGKILL) | sigmask(SIGSTOP)); signotset(&mask); spin_lock_irq(&tsk->sighand->siglock); sig = dequeue_signal(tsk, &mask, info); if (!sig && timeout) { /* * None ready, temporarily unblock those we're interested * while we are sleeping in so that we'll be awakened when |
b182801ab signal: do_sigtim... |
2707 2708 |
* they arrive. Unblocking is always fine, we can avoid * set_current_blocked(). |
943df1485 signal: introduce... |
2709 2710 2711 2712 2713 2714 2715 2716 2717 |
*/ tsk->real_blocked = tsk->blocked; sigandsets(&tsk->blocked, &tsk->blocked, &mask); recalc_sigpending(); spin_unlock_irq(&tsk->sighand->siglock); timeout = schedule_timeout_interruptible(timeout); spin_lock_irq(&tsk->sighand->siglock); |
b182801ab signal: do_sigtim... |
2718 |
__set_task_blocked(tsk, &tsk->real_blocked); |
943df1485 signal: introduce... |
2719 |
siginitset(&tsk->real_blocked, 0); |
b182801ab signal: do_sigtim... |
2720 |
sig = dequeue_signal(tsk, &mask, info); |
943df1485 signal: introduce... |
2721 2722 2723 2724 2725 2726 2727 2728 2729 |
} spin_unlock_irq(&tsk->sighand->siglock); if (sig) return sig; return timeout ? -EINTR : -EAGAIN; } /** |
41c57892a kernel/signal.c: ... |
2730 2731 2732 2733 2734 2735 2736 |
* sys_rt_sigtimedwait - synchronously wait for queued signals specified * in @uthese * @uthese: queued signals to wait for * @uinfo: if non-null, the signal's siginfo is returned here * @uts: upper bound on process time suspension * @sigsetsize: size of sigset_t type */ |
17da2bd90 [CVE-2009-0029] S... |
2737 2738 2739 |
SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese, siginfo_t __user *, uinfo, const struct timespec __user *, uts, size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2740 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2741 2742 2743 |
sigset_t these; struct timespec ts; siginfo_t info; |
943df1485 signal: introduce... |
2744 |
int ret; |
1da177e4c Linux-2.6.12-rc2 |
2745 2746 2747 2748 2749 2750 2751 |
/* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; if (copy_from_user(&these, uthese, sizeof(these))) return -EFAULT; |
5aba085ed kernel/signal.c: ... |
2752 |
|
1da177e4c Linux-2.6.12-rc2 |
2753 2754 2755 |
if (uts) { if (copy_from_user(&ts, uts, sizeof(ts))) return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2756 |
} |
943df1485 signal: introduce... |
2757 |
ret = do_sigtimedwait(&these, &info, uts ? &ts : NULL); |
1da177e4c Linux-2.6.12-rc2 |
2758 |
|
943df1485 signal: introduce... |
2759 2760 2761 |
if (ret > 0 && uinfo) { if (copy_siginfo_to_user(uinfo, &info)) ret = -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2762 2763 2764 2765 |
} return ret; } |
41c57892a kernel/signal.c: ... |
2766 2767 2768 2769 2770 |
/** * sys_kill - send a signal to a process * @pid: the PID of the process * @sig: signal to be sent */ |
17da2bd90 [CVE-2009-0029] S... |
2771 |
SYSCALL_DEFINE2(kill, pid_t, pid, int, sig) |
1da177e4c Linux-2.6.12-rc2 |
2772 2773 2774 2775 2776 2777 |
{ struct siginfo info; info.si_signo = sig; info.si_errno = 0; info.si_code = SI_USER; |
b488893a3 pid namespaces: c... |
2778 |
info.si_pid = task_tgid_vnr(current); |
078de5f70 userns: Store uid... |
2779 |
info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); |
1da177e4c Linux-2.6.12-rc2 |
2780 2781 2782 |
return kill_something_info(sig, &info, pid); } |
30b4ae8a4 signals: split do... |
2783 2784 |
static int do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info) |
1da177e4c Linux-2.6.12-rc2 |
2785 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2786 |
struct task_struct *p; |
30b4ae8a4 signals: split do... |
2787 |
int error = -ESRCH; |
1da177e4c Linux-2.6.12-rc2 |
2788 |
|
3547ff3ae signals: do_tkill... |
2789 |
rcu_read_lock(); |
228ebcbe6 Uninline find_tas... |
2790 |
p = find_task_by_vpid(pid); |
b488893a3 pid namespaces: c... |
2791 |
if (p && (tgid <= 0 || task_tgid_vnr(p) == tgid)) { |
30b4ae8a4 signals: split do... |
2792 |
error = check_kill_permission(sig, info, p); |
1da177e4c Linux-2.6.12-rc2 |
2793 2794 2795 2796 |
/* * The null signal is a permissions and process existence * probe. No signal is actually delivered. */ |
4a30debfb signals: introduc... |
2797 2798 2799 2800 2801 2802 2803 2804 2805 |
if (!error && sig) { error = do_send_sig_info(sig, info, p, false); /* * If lock_task_sighand() failed we pretend the task * dies after receiving the signal. The window is tiny, * and the signal is private anyway. */ if (unlikely(error == -ESRCH)) error = 0; |
1da177e4c Linux-2.6.12-rc2 |
2806 2807 |
} } |
3547ff3ae signals: do_tkill... |
2808 |
rcu_read_unlock(); |
6dd69f106 [PATCH] Unify sys... |
2809 |
|
1da177e4c Linux-2.6.12-rc2 |
2810 2811 |
return error; } |
30b4ae8a4 signals: split do... |
2812 2813 |
static int do_tkill(pid_t tgid, pid_t pid, int sig) { |
b9e146d8e kernel/signal.c: ... |
2814 |
struct siginfo info = {}; |
30b4ae8a4 signals: split do... |
2815 2816 2817 2818 2819 |
info.si_signo = sig; info.si_errno = 0; info.si_code = SI_TKILL; info.si_pid = task_tgid_vnr(current); |
078de5f70 userns: Store uid... |
2820 |
info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); |
30b4ae8a4 signals: split do... |
2821 2822 2823 |
return do_send_specific(tgid, pid, sig, &info); } |
6dd69f106 [PATCH] Unify sys... |
2824 2825 2826 2827 2828 2829 |
/** * sys_tgkill - send signal to one specific thread * @tgid: the thread group ID of the thread * @pid: the PID of the thread * @sig: signal to be sent * |
72fd4a35a [PATCH] Numerous ... |
2830 |
* This syscall also checks the @tgid and returns -ESRCH even if the PID |
6dd69f106 [PATCH] Unify sys... |
2831 2832 2833 |
* exists but it's not belonging to the target process anymore. This * method solves the problem of threads exiting and PIDs getting reused. */ |
a5f8fa9e9 [CVE-2009-0029] S... |
2834 |
SYSCALL_DEFINE3(tgkill, pid_t, tgid, pid_t, pid, int, sig) |
6dd69f106 [PATCH] Unify sys... |
2835 2836 2837 2838 2839 2840 2841 |
{ /* This is only valid for single tasks */ if (pid <= 0 || tgid <= 0) return -EINVAL; return do_tkill(tgid, pid, sig); } |
41c57892a kernel/signal.c: ... |
2842 2843 2844 2845 2846 |
/** * sys_tkill - send signal to one specific task * @pid: the PID of the task * @sig: signal to be sent * |
1da177e4c Linux-2.6.12-rc2 |
2847 2848 |
* Send a signal to only one task, even if it's a CLONE_THREAD task. */ |
a5f8fa9e9 [CVE-2009-0029] S... |
2849 |
SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig) |
1da177e4c Linux-2.6.12-rc2 |
2850 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2851 2852 2853 |
/* This is only valid for single tasks */ if (pid <= 0) return -EINVAL; |
6dd69f106 [PATCH] Unify sys... |
2854 |
return do_tkill(0, pid, sig); |
1da177e4c Linux-2.6.12-rc2 |
2855 |
} |
75907d4d7 generic compat_sy... |
2856 2857 2858 2859 2860 |
static int do_rt_sigqueueinfo(pid_t pid, int sig, siginfo_t *info) { /* Not even root can pretend to send signals from the kernel. * Nor can they impersonate a kill()/tgkill(), which adds source info. */ |
66dd34ad3 signal: allow to ... |
2861 2862 |
if ((info->si_code >= 0 || info->si_code == SI_TKILL) && (task_pid_vnr(current) != pid)) { |
75907d4d7 generic compat_sy... |
2863 2864 2865 2866 2867 2868 2869 2870 2871 |
/* We used to allow any < 0 si_code */ WARN_ON_ONCE(info->si_code < 0); return -EPERM; } info->si_signo = sig; /* POSIX.1b doesn't mention process groups. */ return kill_proc_info(sig, info, pid); } |
41c57892a kernel/signal.c: ... |
2872 2873 2874 2875 2876 2877 |
/** * sys_rt_sigqueueinfo - send signal information to a signal * @pid: the PID of the thread * @sig: signal to be sent * @uinfo: signal info to be sent */ |
a5f8fa9e9 [CVE-2009-0029] S... |
2878 2879 |
SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig, siginfo_t __user *, uinfo) |
1da177e4c Linux-2.6.12-rc2 |
2880 2881 |
{ siginfo_t info; |
1da177e4c Linux-2.6.12-rc2 |
2882 2883 |
if (copy_from_user(&info, uinfo, sizeof(siginfo_t))) return -EFAULT; |
75907d4d7 generic compat_sy... |
2884 2885 |
return do_rt_sigqueueinfo(pid, sig, &info); } |
1da177e4c Linux-2.6.12-rc2 |
2886 |
|
75907d4d7 generic compat_sy... |
2887 |
#ifdef CONFIG_COMPAT |
75907d4d7 generic compat_sy... |
2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 |
COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo, compat_pid_t, pid, int, sig, struct compat_siginfo __user *, uinfo) { siginfo_t info; int ret = copy_siginfo_from_user32(&info, uinfo); if (unlikely(ret)) return ret; return do_rt_sigqueueinfo(pid, sig, &info); |
1da177e4c Linux-2.6.12-rc2 |
2898 |
} |
75907d4d7 generic compat_sy... |
2899 |
#endif |
1da177e4c Linux-2.6.12-rc2 |
2900 |
|
9aae8fc05 switch rt_tgsigqu... |
2901 |
static int do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info) |
62ab4505e signals: implemen... |
2902 2903 2904 2905 2906 2907 |
{ /* This is only valid for single tasks */ if (pid <= 0 || tgid <= 0) return -EINVAL; /* Not even root can pretend to send signals from the kernel. |
da48524eb Prevent rt_sigque... |
2908 2909 |
* Nor can they impersonate a kill()/tgkill(), which adds source info. */ |
66dd34ad3 signal: allow to ... |
2910 2911 |
if (((info->si_code >= 0 || info->si_code == SI_TKILL)) && (task_pid_vnr(current) != pid)) { |
da48524eb Prevent rt_sigque... |
2912 2913 |
/* We used to allow any < 0 si_code */ WARN_ON_ONCE(info->si_code < 0); |
62ab4505e signals: implemen... |
2914 |
return -EPERM; |
da48524eb Prevent rt_sigque... |
2915 |
} |
62ab4505e signals: implemen... |
2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 |
info->si_signo = sig; return do_send_specific(tgid, pid, sig, info); } SYSCALL_DEFINE4(rt_tgsigqueueinfo, pid_t, tgid, pid_t, pid, int, sig, siginfo_t __user *, uinfo) { siginfo_t info; if (copy_from_user(&info, uinfo, sizeof(siginfo_t))) return -EFAULT; return do_rt_tgsigqueueinfo(tgid, pid, sig, &info); } |
9aae8fc05 switch rt_tgsigqu... |
2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 |
#ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo, compat_pid_t, tgid, compat_pid_t, pid, int, sig, struct compat_siginfo __user *, uinfo) { siginfo_t info; if (copy_siginfo_from_user32(&info, uinfo)) return -EFAULT; return do_rt_tgsigqueueinfo(tgid, pid, sig, &info); } #endif |
88531f725 [PATCH] do_sigact... |
2945 |
int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) |
1da177e4c Linux-2.6.12-rc2 |
2946 |
{ |
93585eeaf signals: consolid... |
2947 |
struct task_struct *t = current; |
1da177e4c Linux-2.6.12-rc2 |
2948 |
struct k_sigaction *k; |
71fabd5e4 [PATCH] sigaction... |
2949 |
sigset_t mask; |
1da177e4c Linux-2.6.12-rc2 |
2950 |
|
7ed20e1ad [PATCH] convert t... |
2951 |
if (!valid_signal(sig) || sig < 1 || (act && sig_kernel_only(sig))) |
1da177e4c Linux-2.6.12-rc2 |
2952 |
return -EINVAL; |
93585eeaf signals: consolid... |
2953 |
k = &t->sighand->action[sig-1]; |
1da177e4c Linux-2.6.12-rc2 |
2954 2955 |
spin_lock_irq(¤t->sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2956 2957 2958 2959 |
if (oact) *oact = *k; if (act) { |
9ac95f2f9 [PATCH] do_sigact... |
2960 2961 |
sigdelsetmask(&act->sa.sa_mask, sigmask(SIGKILL) | sigmask(SIGSTOP)); |
88531f725 [PATCH] do_sigact... |
2962 |
*k = *act; |
1da177e4c Linux-2.6.12-rc2 |
2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 |
/* * POSIX 3.3.1.3: * "Setting a signal action to SIG_IGN for a signal that is * pending shall cause the pending signal to be discarded, * whether or not it is blocked." * * "Setting a signal action to SIG_DFL for a signal that is * pending and whose default action is to ignore the signal * (for example, SIGCHLD), shall cause the pending signal to * be discarded, whether or not it is blocked" */ |
35de254dc tracehook: traceh... |
2974 |
if (sig_handler_ignored(sig_handler(t, sig), sig)) { |
71fabd5e4 [PATCH] sigaction... |
2975 2976 2977 |
sigemptyset(&mask); sigaddset(&mask, sig); rm_from_queue_full(&mask, &t->signal->shared_pending); |
1da177e4c Linux-2.6.12-rc2 |
2978 |
do { |
71fabd5e4 [PATCH] sigaction... |
2979 |
rm_from_queue_full(&mask, &t->pending); |
1da177e4c Linux-2.6.12-rc2 |
2980 2981 |
t = next_thread(t); } while (t != current); |
1da177e4c Linux-2.6.12-rc2 |
2982 |
} |
1da177e4c Linux-2.6.12-rc2 |
2983 2984 2985 2986 2987 |
} spin_unlock_irq(¤t->sighand->siglock); return 0; } |
e9b04b5b6 make do_sigaltsta... |
2988 |
static int |
1da177e4c Linux-2.6.12-rc2 |
2989 2990 2991 2992 |
do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long sp) { stack_t oss; int error; |
0083fc2c5 do_sigaltstack: a... |
2993 2994 2995 |
oss.ss_sp = (void __user *) current->sas_ss_sp; oss.ss_size = current->sas_ss_size; oss.ss_flags = sas_ss_flags(sp); |
1da177e4c Linux-2.6.12-rc2 |
2996 2997 2998 2999 3000 3001 3002 |
if (uss) { void __user *ss_sp; size_t ss_size; int ss_flags; error = -EFAULT; |
0dd8486b5 do_sigaltstack: s... |
3003 3004 3005 3006 3007 3008 |
if (!access_ok(VERIFY_READ, uss, sizeof(*uss))) goto out; error = __get_user(ss_sp, &uss->ss_sp) | __get_user(ss_flags, &uss->ss_flags) | __get_user(ss_size, &uss->ss_size); if (error) |
1da177e4c Linux-2.6.12-rc2 |
3009 3010 3011 3012 3013 3014 3015 3016 |
goto out; error = -EPERM; if (on_sig_stack(sp)) goto out; error = -EINVAL; /* |
5aba085ed kernel/signal.c: ... |
3017 |
* Note - this code used to test ss_flags incorrectly: |
1da177e4c Linux-2.6.12-rc2 |
3018 3019 3020 |
* old code may have been written using ss_flags==0 * to mean ss_flags==SS_ONSTACK (as this was the only * way that worked) - this fix preserves that older |
5aba085ed kernel/signal.c: ... |
3021 |
* mechanism. |
1da177e4c Linux-2.6.12-rc2 |
3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 |
*/ if (ss_flags != SS_DISABLE && ss_flags != SS_ONSTACK && ss_flags != 0) goto out; if (ss_flags == SS_DISABLE) { ss_size = 0; ss_sp = NULL; } else { error = -ENOMEM; if (ss_size < MINSIGSTKSZ) goto out; } current->sas_ss_sp = (unsigned long) ss_sp; current->sas_ss_size = ss_size; } |
0083fc2c5 do_sigaltstack: a... |
3038 |
error = 0; |
1da177e4c Linux-2.6.12-rc2 |
3039 3040 |
if (uoss) { error = -EFAULT; |
0083fc2c5 do_sigaltstack: a... |
3041 |
if (!access_ok(VERIFY_WRITE, uoss, sizeof(*uoss))) |
1da177e4c Linux-2.6.12-rc2 |
3042 |
goto out; |
0083fc2c5 do_sigaltstack: a... |
3043 3044 3045 |
error = __put_user(oss.ss_sp, &uoss->ss_sp) | __put_user(oss.ss_size, &uoss->ss_size) | __put_user(oss.ss_flags, &uoss->ss_flags); |
1da177e4c Linux-2.6.12-rc2 |
3046 |
} |
1da177e4c Linux-2.6.12-rc2 |
3047 3048 3049 |
out: return error; } |
6bf9adfc9 introduce generic... |
3050 3051 3052 3053 |
SYSCALL_DEFINE2(sigaltstack,const stack_t __user *,uss, stack_t __user *,uoss) { return do_sigaltstack(uss, uoss, current_user_stack_pointer()); } |
1da177e4c Linux-2.6.12-rc2 |
3054 |
|
5c49574ff new helper: resto... |
3055 3056 3057 3058 3059 3060 |
int restore_altstack(const stack_t __user *uss) { int err = do_sigaltstack(uss, NULL, current_user_stack_pointer()); /* squash all but EFAULT for now */ return err == -EFAULT ? err : 0; } |
c40702c49 new helpers: __sa... |
3061 3062 3063 3064 3065 3066 3067 |
int __save_altstack(stack_t __user *uss, unsigned long sp) { struct task_struct *t = current; return __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) | __put_user(sas_ss_flags(sp), &uss->ss_flags) | __put_user(t->sas_ss_size, &uss->ss_size); } |
902684395 generic compat_sy... |
3068 |
#ifdef CONFIG_COMPAT |
90228fc11 switch compat_sys... |
3069 3070 3071 |
COMPAT_SYSCALL_DEFINE2(sigaltstack, const compat_stack_t __user *, uss_ptr, compat_stack_t __user *, uoss_ptr) |
902684395 generic compat_sy... |
3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 |
{ stack_t uss, uoss; int ret; mm_segment_t seg; if (uss_ptr) { compat_stack_t uss32; memset(&uss, 0, sizeof(stack_t)); if (copy_from_user(&uss32, uss_ptr, sizeof(compat_stack_t))) return -EFAULT; uss.ss_sp = compat_ptr(uss32.ss_sp); uss.ss_flags = uss32.ss_flags; uss.ss_size = uss32.ss_size; } seg = get_fs(); set_fs(KERNEL_DS); ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL), (stack_t __force __user *) &uoss, compat_user_stack_pointer()); set_fs(seg); if (ret >= 0 && uoss_ptr) { if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(compat_stack_t)) || __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) || __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) || __put_user(uoss.ss_size, &uoss_ptr->ss_size)) ret = -EFAULT; } return ret; } int compat_restore_altstack(const compat_stack_t __user *uss) { int err = compat_sys_sigaltstack(uss, NULL); /* squash all but -EFAULT for now */ return err == -EFAULT ? err : 0; } |
c40702c49 new helpers: __sa... |
3109 3110 3111 3112 3113 3114 3115 3116 |
int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp) { struct task_struct *t = current; return __put_user(ptr_to_compat((void __user *)t->sas_ss_sp), &uss->ss_sp) | __put_user(sas_ss_flags(sp), &uss->ss_flags) | __put_user(t->sas_ss_size, &uss->ss_size); } |
902684395 generic compat_sy... |
3117 |
#endif |
1da177e4c Linux-2.6.12-rc2 |
3118 3119 |
#ifdef __ARCH_WANT_SYS_SIGPENDING |
41c57892a kernel/signal.c: ... |
3120 3121 3122 3123 |
/** * sys_sigpending - examine pending signals * @set: where mask of pending signal is returned */ |
b290ebe2c [CVE-2009-0029] S... |
3124 |
SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set) |
1da177e4c Linux-2.6.12-rc2 |
3125 |
{ |
fe9c1db2c generic compat_sy... |
3126 |
return sys_rt_sigpending((sigset_t __user *)set, sizeof(old_sigset_t)); |
1da177e4c Linux-2.6.12-rc2 |
3127 3128 3129 3130 3131 |
} #endif #ifdef __ARCH_WANT_SYS_SIGPROCMASK |
41c57892a kernel/signal.c: ... |
3132 3133 3134 |
/** * sys_sigprocmask - examine and change blocked signals * @how: whether to add, remove, or set signals |
b013c3992 signal: cleanup s... |
3135 |
* @nset: signals to add or remove (if non-null) |
41c57892a kernel/signal.c: ... |
3136 3137 |
* @oset: previous value of signal mask if non-null * |
5aba085ed kernel/signal.c: ... |
3138 3139 3140 |
* Some platforms have their own version with special arguments; * others support only sys_rt_sigprocmask. */ |
1da177e4c Linux-2.6.12-rc2 |
3141 |
|
b013c3992 signal: cleanup s... |
3142 |
SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset, |
b290ebe2c [CVE-2009-0029] S... |
3143 |
old_sigset_t __user *, oset) |
1da177e4c Linux-2.6.12-rc2 |
3144 |
{ |
1da177e4c Linux-2.6.12-rc2 |
3145 |
old_sigset_t old_set, new_set; |
2e4f7c776 signal: sys_sigpr... |
3146 |
sigset_t new_blocked; |
1da177e4c Linux-2.6.12-rc2 |
3147 |
|
b013c3992 signal: cleanup s... |
3148 |
old_set = current->blocked.sig[0]; |
1da177e4c Linux-2.6.12-rc2 |
3149 |
|
b013c3992 signal: cleanup s... |
3150 3151 3152 |
if (nset) { if (copy_from_user(&new_set, nset, sizeof(*nset))) return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
3153 |
|
2e4f7c776 signal: sys_sigpr... |
3154 |
new_blocked = current->blocked; |
1da177e4c Linux-2.6.12-rc2 |
3155 |
|
1da177e4c Linux-2.6.12-rc2 |
3156 |
switch (how) { |
1da177e4c Linux-2.6.12-rc2 |
3157 |
case SIG_BLOCK: |
2e4f7c776 signal: sys_sigpr... |
3158 |
sigaddsetmask(&new_blocked, new_set); |
1da177e4c Linux-2.6.12-rc2 |
3159 3160 |
break; case SIG_UNBLOCK: |
2e4f7c776 signal: sys_sigpr... |
3161 |
sigdelsetmask(&new_blocked, new_set); |
1da177e4c Linux-2.6.12-rc2 |
3162 3163 |
break; case SIG_SETMASK: |
2e4f7c776 signal: sys_sigpr... |
3164 |
new_blocked.sig[0] = new_set; |
1da177e4c Linux-2.6.12-rc2 |
3165 |
break; |
2e4f7c776 signal: sys_sigpr... |
3166 3167 |
default: return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
3168 |
} |
0c4a84234 signals: set_curr... |
3169 |
set_current_blocked(&new_blocked); |
b013c3992 signal: cleanup s... |
3170 3171 3172 |
} if (oset) { |
1da177e4c Linux-2.6.12-rc2 |
3173 |
if (copy_to_user(oset, &old_set, sizeof(*oset))) |
b013c3992 signal: cleanup s... |
3174 |
return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
3175 |
} |
b013c3992 signal: cleanup s... |
3176 3177 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
3178 3179 |
} #endif /* __ARCH_WANT_SYS_SIGPROCMASK */ |
eaca6eae3 sanitize rt_sigac... |
3180 |
#ifndef CONFIG_ODD_RT_SIGACTION |
41c57892a kernel/signal.c: ... |
3181 3182 3183 |
/** * sys_rt_sigaction - alter an action taken by a process * @sig: signal to be sent |
f9fa0bc1f signal.c: fix err... |
3184 3185 |
* @act: new sigaction * @oact: used to save the previous sigaction |
41c57892a kernel/signal.c: ... |
3186 3187 |
* @sigsetsize: size of sigset_t type */ |
d4e82042c [CVE-2009-0029] S... |
3188 3189 3190 3191 |
SYSCALL_DEFINE4(rt_sigaction, int, sig, const struct sigaction __user *, act, struct sigaction __user *, oact, size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 |
{ struct k_sigaction new_sa, old_sa; int ret = -EINVAL; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) goto out; if (act) { if (copy_from_user(&new_sa.sa, act, sizeof(new_sa.sa))) return -EFAULT; } ret = do_sigaction(sig, act ? &new_sa : NULL, oact ? &old_sa : NULL); if (!ret && oact) { if (copy_to_user(oact, &old_sa.sa, sizeof(old_sa.sa))) return -EFAULT; } out: return ret; } |
08d32fe50 generic sys_compa... |
3214 |
#ifdef CONFIG_COMPAT |
08d32fe50 generic sys_compa... |
3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 |
COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, const struct compat_sigaction __user *, act, struct compat_sigaction __user *, oact, compat_size_t, sigsetsize) { struct k_sigaction new_ka, old_ka; compat_sigset_t mask; #ifdef __ARCH_HAS_SA_RESTORER compat_uptr_t restorer; #endif int ret; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(compat_sigset_t)) return -EINVAL; if (act) { compat_uptr_t handler; ret = get_user(handler, &act->sa_handler); new_ka.sa.sa_handler = compat_ptr(handler); #ifdef __ARCH_HAS_SA_RESTORER ret |= get_user(restorer, &act->sa_restorer); new_ka.sa.sa_restorer = compat_ptr(restorer); #endif ret |= copy_from_user(&mask, &act->sa_mask, sizeof(mask)); ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags); if (ret) return -EFAULT; sigset_from_compat(&new_ka.sa.sa_mask, &mask); } ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); if (!ret && oact) { sigset_to_compat(&mask, &old_ka.sa.sa_mask); ret = put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler); ret |= copy_to_user(&oact->sa_mask, &mask, sizeof(mask)); ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags); #ifdef __ARCH_HAS_SA_RESTORER ret |= put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer); #endif } return ret; } #endif |
eaca6eae3 sanitize rt_sigac... |
3261 |
#endif /* !CONFIG_ODD_RT_SIGACTION */ |
1da177e4c Linux-2.6.12-rc2 |
3262 |
|
495dfbf76 generic sys_sigac... |
3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 |
#ifdef CONFIG_OLD_SIGACTION SYSCALL_DEFINE3(sigaction, int, sig, const struct old_sigaction __user *, act, struct old_sigaction __user *, oact) { struct k_sigaction new_ka, old_ka; int ret; if (act) { old_sigset_t mask; if (!access_ok(VERIFY_READ, act, sizeof(*act)) || __get_user(new_ka.sa.sa_handler, &act->sa_handler) || __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) || __get_user(new_ka.sa.sa_flags, &act->sa_flags) || __get_user(mask, &act->sa_mask)) return -EFAULT; #ifdef __ARCH_HAS_KA_RESTORER new_ka.ka_restorer = NULL; #endif siginitset(&new_ka.sa.sa_mask, mask); } ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); if (!ret && oact) { if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) || __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) return -EFAULT; } return ret; } #endif #ifdef CONFIG_COMPAT_OLD_SIGACTION COMPAT_SYSCALL_DEFINE3(sigaction, int, sig, const struct compat_old_sigaction __user *, act, struct compat_old_sigaction __user *, oact) { struct k_sigaction new_ka, old_ka; int ret; compat_old_sigset_t mask; compat_uptr_t handler, restorer; if (act) { if (!access_ok(VERIFY_READ, act, sizeof(*act)) || __get_user(handler, &act->sa_handler) || __get_user(restorer, &act->sa_restorer) || __get_user(new_ka.sa.sa_flags, &act->sa_flags) || __get_user(mask, &act->sa_mask)) return -EFAULT; #ifdef __ARCH_HAS_KA_RESTORER new_ka.ka_restorer = NULL; #endif new_ka.sa.sa_handler = compat_ptr(handler); new_ka.sa.sa_restorer = compat_ptr(restorer); siginitset(&new_ka.sa.sa_mask, mask); } ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); if (!ret && oact) { if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || __put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler) || __put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer) || __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) return -EFAULT; } return ret; } #endif |
1da177e4c Linux-2.6.12-rc2 |
3340 3341 3342 3343 3344 3345 |
#ifdef __ARCH_WANT_SYS_SGETMASK /* * For backwards compatibility. Functionality superseded by sigprocmask. */ |
a5f8fa9e9 [CVE-2009-0029] S... |
3346 |
SYSCALL_DEFINE0(sgetmask) |
1da177e4c Linux-2.6.12-rc2 |
3347 3348 3349 3350 |
{ /* SMP safe */ return current->blocked.sig[0]; } |
a5f8fa9e9 [CVE-2009-0029] S... |
3351 |
SYSCALL_DEFINE1(ssetmask, int, newmask) |
1da177e4c Linux-2.6.12-rc2 |
3352 |
{ |
c1095c6da signals: sys_sset... |
3353 3354 |
int old = current->blocked.sig[0]; sigset_t newset; |
1da177e4c Linux-2.6.12-rc2 |
3355 |
|
5ba53ff64 signals: sys_sset... |
3356 |
siginitset(&newset, newmask); |
c1095c6da signals: sys_sset... |
3357 |
set_current_blocked(&newset); |
1da177e4c Linux-2.6.12-rc2 |
3358 3359 3360 3361 3362 3363 3364 3365 3366 |
return old; } #endif /* __ARCH_WANT_SGETMASK */ #ifdef __ARCH_WANT_SYS_SIGNAL /* * For backwards compatibility. Functionality superseded by sigaction. */ |
a5f8fa9e9 [CVE-2009-0029] S... |
3367 |
SYSCALL_DEFINE2(signal, int, sig, __sighandler_t, handler) |
1da177e4c Linux-2.6.12-rc2 |
3368 3369 3370 3371 3372 3373 |
{ struct k_sigaction new_sa, old_sa; int ret; new_sa.sa.sa_handler = handler; new_sa.sa.sa_flags = SA_ONESHOT | SA_NOMASK; |
c70d3d703 [PATCH] sys_signa... |
3374 |
sigemptyset(&new_sa.sa.sa_mask); |
1da177e4c Linux-2.6.12-rc2 |
3375 3376 3377 3378 3379 3380 3381 3382 |
ret = do_sigaction(sig, &new_sa, &old_sa); return ret ? ret : (unsigned long)old_sa.sa.sa_handler; } #endif /* __ARCH_WANT_SYS_SIGNAL */ #ifdef __ARCH_WANT_SYS_PAUSE |
a5f8fa9e9 [CVE-2009-0029] S... |
3383 |
SYSCALL_DEFINE0(pause) |
1da177e4c Linux-2.6.12-rc2 |
3384 |
{ |
d92fcf055 signal: sys_pause... |
3385 3386 3387 3388 |
while (!signal_pending(current)) { current->state = TASK_INTERRUPTIBLE; schedule(); } |
1da177e4c Linux-2.6.12-rc2 |
3389 3390 3391 3392 |
return -ERESTARTNOHAND; } #endif |
68f3f16d9 new helper: sigsu... |
3393 3394 |
int sigsuspend(sigset_t *set) { |
68f3f16d9 new helper: sigsu... |
3395 3396 3397 3398 3399 3400 3401 3402 |
current->saved_sigmask = current->blocked; set_current_blocked(set); current->state = TASK_INTERRUPTIBLE; schedule(); set_restore_sigmask(); return -ERESTARTNOHAND; } |
68f3f16d9 new helper: sigsu... |
3403 |
|
41c57892a kernel/signal.c: ... |
3404 3405 3406 3407 3408 3409 |
/** * sys_rt_sigsuspend - replace the signal mask for a value with the * @unewset value until a signal is received * @unewset: new signal mask value * @sigsetsize: size of sigset_t type */ |
d4e82042c [CVE-2009-0029] S... |
3410 |
SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *, unewset, size_t, sigsetsize) |
150256d8a [PATCH] Generic s... |
3411 3412 3413 3414 3415 3416 3417 3418 3419 |
{ sigset_t newset; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; if (copy_from_user(&newset, unewset, sizeof(newset))) return -EFAULT; |
68f3f16d9 new helper: sigsu... |
3420 |
return sigsuspend(&newset); |
150256d8a [PATCH] Generic s... |
3421 |
} |
ad4b65a43 consolidate rt_si... |
3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 |
#ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(rt_sigsuspend, compat_sigset_t __user *, unewset, compat_size_t, sigsetsize) { #ifdef __BIG_ENDIAN sigset_t newset; compat_sigset_t newset32; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t))) return -EFAULT; sigset_from_compat(&newset, &newset32); return sigsuspend(&newset); #else /* on little-endian bitmaps don't care about granularity */ return sys_rt_sigsuspend((sigset_t __user *)unewset, sigsetsize); #endif } #endif |
150256d8a [PATCH] Generic s... |
3444 |
|
0a0e8cdf7 old sigsuspend va... |
3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 |
#ifdef CONFIG_OLD_SIGSUSPEND SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask) { sigset_t blocked; siginitset(&blocked, mask); return sigsuspend(&blocked); } #endif #ifdef CONFIG_OLD_SIGSUSPEND3 SYSCALL_DEFINE3(sigsuspend, int, unused1, int, unused2, old_sigset_t, mask) { sigset_t blocked; siginitset(&blocked, mask); return sigsuspend(&blocked); } #endif |
150256d8a [PATCH] Generic s... |
3461 |
|
f269fdd18 [PATCH] NOMMU: mo... |
3462 3463 3464 3465 |
__attribute__((weak)) const char *arch_vma_name(struct vm_area_struct *vma) { return NULL; } |
1da177e4c Linux-2.6.12-rc2 |
3466 3467 |
void __init signals_init(void) { |
0a31bd5f2 KMEM_CACHE(): sim... |
3468 |
sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC); |
1da177e4c Linux-2.6.12-rc2 |
3469 |
} |
67fc4e0cb kdb: core for kgd... |
3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 |
#ifdef CONFIG_KGDB_KDB #include <linux/kdb.h> /* * kdb_send_sig_info - Allows kdb to send signals without exposing * signal internals. This function checks if the required locks are * available before calling the main signal code, to avoid kdb * deadlocks. */ void kdb_send_sig_info(struct task_struct *t, struct siginfo *info) { static struct task_struct *kdb_prev_t; int sig, new_t; if (!spin_trylock(&t->sighand->siglock)) { kdb_printf("Can't do kill command now. " "The sigmask lock is held somewhere else in " "kernel, try again later "); return; } spin_unlock(&t->sighand->siglock); new_t = kdb_prev_t != t; kdb_prev_t = t; if (t->state != TASK_RUNNING && new_t) { kdb_printf("Process is not RUNNING, sending a signal from " "kdb risks deadlock " "on the run queue locks. " "The signal has _not_ been sent. " "Reissue the kill command if you want to risk " "the deadlock. "); return; } sig = info->si_signo; if (send_sig_info(sig, info, t)) kdb_printf("Fail to deliver Signal %d to process %d. ", sig, t->pid); else kdb_printf("Signal %d is sent to process %d. ", sig, t->pid); } #endif /* CONFIG_KGDB_KDB */ |