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kernel/signal.c
84.6 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> #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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#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 "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, int from_ancestor_ns) |
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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 && !from_ancestor_ns) |
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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, int from_ancestor_ns) |
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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, from_ancestor_ns)) |
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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) | \ sigmask(SIGTRAP) | sigmask(SIGFPE)) |
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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; 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; |
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/* if ptraced, let the tracer determine */ return !tsk->ptrace; |
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} |
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/* * Notify the system that a driver wants to block all signals for this |
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* 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 |
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* can use to determine if the signal should be blocked or not. */ |
1da177e4c Linux-2.6.12-rc2 |
486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 |
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... |
511 |
static void collect_signal(int sig, struct sigpending *list, siginfo_t *info) |
1da177e4c Linux-2.6.12-rc2 |
512 513 |
{ struct sigqueue *q, *first = NULL; |
1da177e4c Linux-2.6.12-rc2 |
514 |
|
1da177e4c Linux-2.6.12-rc2 |
515 516 517 518 519 520 |
/* * 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_... |
521 522 |
if (first) goto still_pending; |
1da177e4c Linux-2.6.12-rc2 |
523 524 525 |
first = q; } } |
d44342076 signals: collect_... |
526 527 |
sigdelset(&list->signal, sig); |
1da177e4c Linux-2.6.12-rc2 |
528 |
if (first) { |
d44342076 signals: collect_... |
529 |
still_pending: |
1da177e4c Linux-2.6.12-rc2 |
530 531 532 |
list_del_init(&first->list); copy_siginfo(info, &first->info); __sigqueue_free(first); |
1da177e4c Linux-2.6.12-rc2 |
533 |
} else { |
5aba085ed kernel/signal.c: ... |
534 535 536 537 |
/* * 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 |
538 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
539 540 |
info->si_signo = sig; info->si_errno = 0; |
7486e5d9f signals: cosmetic... |
541 |
info->si_code = SI_USER; |
1da177e4c Linux-2.6.12-rc2 |
542 543 544 |
info->si_pid = 0; info->si_uid = 0; } |
1da177e4c Linux-2.6.12-rc2 |
545 546 547 548 549 |
} static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, siginfo_t *info) { |
27d91e07f [PATCH] __dequeue... |
550 |
int sig = next_signal(pending, mask); |
1da177e4c Linux-2.6.12-rc2 |
551 |
|
1da177e4c Linux-2.6.12-rc2 |
552 553 554 555 556 557 558 559 560 |
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... |
561 |
collect_signal(sig, pending, info); |
1da177e4c Linux-2.6.12-rc2 |
562 |
} |
1da177e4c Linux-2.6.12-rc2 |
563 564 565 566 567 |
return sig; } /* |
5aba085ed kernel/signal.c: ... |
568 |
* Dequeue a signal and return the element to the caller, which is |
1da177e4c Linux-2.6.12-rc2 |
569 570 571 572 573 574 |
* 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... |
575 |
int signr; |
caec4e8dc Fix signalfd inte... |
576 577 578 579 |
/* We only dequeue private signals from ourselves, we don't let * signalfd steal them */ |
b8fceee17 signalfd simplifi... |
580 |
signr = __dequeue_signal(&tsk->pending, mask, info); |
8bfd9a7a2 [PATCH] hrtimers:... |
581 |
if (!signr) { |
1da177e4c Linux-2.6.12-rc2 |
582 583 |
signr = __dequeue_signal(&tsk->signal->shared_pending, mask, info); |
8bfd9a7a2 [PATCH] hrtimers:... |
584 585 586 587 588 589 |
/* * 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: ... |
590 |
* compliant with the old way of self-restarting |
8bfd9a7a2 [PATCH] hrtimers:... |
591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 |
* 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... |
608 |
|
b8fceee17 signalfd simplifi... |
609 |
recalc_sigpending(); |
c5363d036 signals: clean de... |
610 611 612 613 |
if (!signr) return 0; if (unlikely(sig_kernel_stop(signr))) { |
8bfd9a7a2 [PATCH] hrtimers:... |
614 615 616 617 618 619 620 621 622 623 624 625 |
/* * 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... |
626 |
current->jobctl |= JOBCTL_STOP_DEQUEUED; |
8bfd9a7a2 [PATCH] hrtimers:... |
627 |
} |
c5363d036 signals: clean de... |
628 |
if ((info->si_code & __SI_MASK) == __SI_TIMER && info->si_sys_private) { |
1da177e4c Linux-2.6.12-rc2 |
629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 |
/* * 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 */ void signal_wake_up(struct task_struct *t, int resume) { unsigned int mask; set_tsk_thread_flag(t, TIF_SIGPENDING); /* |
f021a3c2b Add TASK_WAKEKILL |
660 661 |
* For SIGKILL, we want to wake it up in the stopped/traced/killable * case. We don't check t->state here because there is a race with it |
1da177e4c Linux-2.6.12-rc2 |
662 663 664 665 666 667 |
* 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. */ mask = TASK_INTERRUPTIBLE; if (resume) |
f021a3c2b Add TASK_WAKEKILL |
668 |
mask |= TASK_WAKEKILL; |
1da177e4c Linux-2.6.12-rc2 |
669 670 671 672 673 674 675 676 677 |
if (!wake_up_state(t, mask)) 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... |
678 679 680 681 682 683 684 685 686 687 688 689 |
* * 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... |
690 |
sigandnsets(&s->signal, &s->signal, mask); |
71fabd5e4 [PATCH] sigaction... |
691 692 693 694 695 696 697 698 699 700 701 702 703 |
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 |
704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 |
*/ 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... |
722 723 724 725 726 727 728 729 730 731 |
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 |
732 |
/* |
39fd33933 userns: allow kil... |
733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 |
* 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); if (cred->user->user_ns == tcred->user->user_ns && (cred->euid == tcred->suid || cred->euid == tcred->uid || cred->uid == tcred->suid || cred->uid == tcred->uid)) return 1; if (ns_capable(tcred->user->user_ns, CAP_KILL)) return 1; return 0; } /* |
1da177e4c Linux-2.6.12-rc2 |
754 |
* Bad permissions for sending the signal |
694f690d2 CRED: Fix RCU war... |
755 |
* - the caller must hold the RCU read lock |
1da177e4c Linux-2.6.12-rc2 |
756 757 758 759 |
*/ static int check_kill_permission(int sig, struct siginfo *info, struct task_struct *t) { |
2e2ba22ea signals: check_ki... |
760 |
struct pid *sid; |
3b5e9e53c signals: cleanup ... |
761 |
int error; |
7ed20e1ad [PATCH] convert t... |
762 |
if (!valid_signal(sig)) |
3b5e9e53c signals: cleanup ... |
763 |
return -EINVAL; |
614c517d7 signals: SEND_SIG... |
764 |
if (!si_fromuser(info)) |
3b5e9e53c signals: cleanup ... |
765 |
return 0; |
e54dc2431 [PATCH] audit sig... |
766 |
|
3b5e9e53c signals: cleanup ... |
767 768 |
error = audit_signal_info(sig, t); /* Let audit system see the signal */ if (error) |
1da177e4c Linux-2.6.12-rc2 |
769 |
return error; |
3b5e9e53c signals: cleanup ... |
770 |
|
065add394 signals: check_ki... |
771 |
if (!same_thread_group(current, t) && |
39fd33933 userns: allow kil... |
772 |
!kill_ok_by_cred(t)) { |
2e2ba22ea signals: check_ki... |
773 774 |
switch (sig) { case SIGCONT: |
2e2ba22ea signals: check_ki... |
775 |
sid = task_session(t); |
2e2ba22ea signals: check_ki... |
776 777 778 779 780 781 782 783 784 785 |
/* * 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... |
786 |
|
e54dc2431 [PATCH] audit sig... |
787 |
return security_task_kill(t, info, sig, 0); |
1da177e4c Linux-2.6.12-rc2 |
788 |
} |
fb1d910c1 ptrace: implement... |
789 790 791 792 793 794 795 796 |
/** * 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... |
797 798 799 800 801 |
* 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... |
802 803 804 805 806 807 808 809 810 811 |
* * 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); |
544b2c91a ptrace: implement... |
812 |
signal_wake_up(t, t->jobctl & JOBCTL_LISTENING); |
fb1d910c1 ptrace: implement... |
813 |
} |
1da177e4c Linux-2.6.12-rc2 |
814 |
/* |
7e695a5ef signals: fold sig... |
815 816 |
* 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 |
817 818 |
* 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... |
819 820 821 822 |
* 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 |
823 |
*/ |
921cf9f63 signals: protect ... |
824 |
static int prepare_signal(int sig, struct task_struct *p, int from_ancestor_ns) |
1da177e4c Linux-2.6.12-rc2 |
825 |
{ |
ad16a4606 handle_stop_signa... |
826 |
struct signal_struct *signal = p->signal; |
1da177e4c Linux-2.6.12-rc2 |
827 |
struct task_struct *t; |
7e695a5ef signals: fold sig... |
828 |
if (unlikely(signal->flags & SIGNAL_GROUP_EXIT)) { |
1da177e4c Linux-2.6.12-rc2 |
829 |
/* |
7e695a5ef signals: fold sig... |
830 |
* The process is in the middle of dying, nothing to do. |
1da177e4c Linux-2.6.12-rc2 |
831 |
*/ |
7e695a5ef signals: fold sig... |
832 |
} else if (sig_kernel_stop(sig)) { |
1da177e4c Linux-2.6.12-rc2 |
833 834 835 |
/* * This is a stop signal. Remove SIGCONT from all queues. */ |
ad16a4606 handle_stop_signa... |
836 |
rm_from_queue(sigmask(SIGCONT), &signal->shared_pending); |
1da177e4c Linux-2.6.12-rc2 |
837 838 839 |
t = p; do { rm_from_queue(sigmask(SIGCONT), &t->pending); |
ad16a4606 handle_stop_signa... |
840 |
} while_each_thread(p, t); |
1da177e4c Linux-2.6.12-rc2 |
841 |
} else if (sig == SIGCONT) { |
fc321d2e6 handle_stop_signa... |
842 |
unsigned int why; |
1da177e4c Linux-2.6.12-rc2 |
843 |
/* |
1deac632f signal: prepare_s... |
844 |
* Remove all stop signals from all queues, wake all threads. |
1da177e4c Linux-2.6.12-rc2 |
845 |
*/ |
ad16a4606 handle_stop_signa... |
846 |
rm_from_queue(SIG_KERNEL_STOP_MASK, &signal->shared_pending); |
1da177e4c Linux-2.6.12-rc2 |
847 848 |
t = p; do { |
3759a0d94 job control: intr... |
849 |
task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING); |
1da177e4c Linux-2.6.12-rc2 |
850 |
rm_from_queue(SIG_KERNEL_STOP_MASK, &t->pending); |
fb1d910c1 ptrace: implement... |
851 852 853 854 |
if (likely(!(t->ptrace & PT_SEIZED))) wake_up_state(t, __TASK_STOPPED); else ptrace_trap_notify(t); |
ad16a4606 handle_stop_signa... |
855 |
} while_each_thread(p, t); |
1da177e4c Linux-2.6.12-rc2 |
856 |
|
fc321d2e6 handle_stop_signa... |
857 858 859 860 861 862 863 864 865 |
/* * 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... |
866 |
if (signal->flags & SIGNAL_STOP_STOPPED) |
fc321d2e6 handle_stop_signa... |
867 |
why |= SIGNAL_CLD_CONTINUED; |
ad16a4606 handle_stop_signa... |
868 |
else if (signal->group_stop_count) |
fc321d2e6 handle_stop_signa... |
869 870 871 |
why |= SIGNAL_CLD_STOPPED; if (why) { |
021e1ae3d signals: document... |
872 |
/* |
ae6d2ed7b signals: tracehoo... |
873 |
* The first thread which returns from do_signal_stop() |
021e1ae3d signals: document... |
874 875 876 |
* will take ->siglock, notice SIGNAL_CLD_MASK, and * notify its parent. See get_signal_to_deliver(). */ |
ad16a4606 handle_stop_signa... |
877 878 879 |
signal->flags = why | SIGNAL_STOP_CONTINUED; signal->group_stop_count = 0; signal->group_exit_code = 0; |
1da177e4c Linux-2.6.12-rc2 |
880 |
} |
1da177e4c Linux-2.6.12-rc2 |
881 |
} |
7e695a5ef signals: fold sig... |
882 |
|
921cf9f63 signals: protect ... |
883 |
return !sig_ignored(p, sig, from_ancestor_ns); |
1da177e4c Linux-2.6.12-rc2 |
884 |
} |
71f11dc02 signals: move the... |
885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 |
/* * 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... |
905 |
static void complete_signal(int sig, struct task_struct *p, int group) |
71f11dc02 signals: move the... |
906 907 908 909 910 911 912 913 914 915 916 917 |
{ 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... |
918 |
else if (!group || thread_group_empty(p)) |
71f11dc02 signals: move the... |
919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 |
/* * 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... |
946 947 |
if (sig_fatal(p, sig) && !(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) && |
71f11dc02 signals: move the... |
948 |
!sigismember(&t->real_blocked, sig) && |
a288eecce ptrace: kill triv... |
949 |
(sig == SIGKILL || !t->ptrace)) { |
71f11dc02 signals: move the... |
950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 |
/* * 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... |
965 |
task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); |
71f11dc02 signals: move the... |
966 967 968 969 970 971 972 973 974 975 976 977 978 979 |
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... |
980 981 982 983 |
static inline int legacy_queue(struct sigpending *signals, int sig) { return (sig < SIGRTMIN) && sigismember(&signals->signal, sig); } |
6b550f949 user namespace: m... |
984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 |
/* * map the uid in struct cred into user namespace *ns */ static inline uid_t map_cred_ns(const struct cred *cred, struct user_namespace *ns) { return user_ns_map_uid(ns, cred, cred->uid); } #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; info->si_uid = user_ns_map_uid(task_cred_xxx(t, user_ns), current_cred(), info->si_uid); } #else static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t) { return; } #endif |
7978b567d signals: add from... |
1011 1012 |
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 |
1013 |
{ |
2ca3515aa signals: change s... |
1014 |
struct sigpending *pending; |
6e65acba7 signals: move han... |
1015 |
struct sigqueue *q; |
7a0aeb14e signal: fix __sen... |
1016 |
int override_rlimit; |
1da177e4c Linux-2.6.12-rc2 |
1017 |
|
d1eb650ff tracepoint: Move ... |
1018 |
trace_signal_generate(sig, info, t); |
0a16b6075 tracing, sched: L... |
1019 |
|
6e65acba7 signals: move han... |
1020 |
assert_spin_locked(&t->sighand->siglock); |
921cf9f63 signals: protect ... |
1021 1022 |
if (!prepare_signal(sig, t, from_ancestor_ns)) |
7e695a5ef signals: fold sig... |
1023 |
return 0; |
2ca3515aa signals: change s... |
1024 1025 |
pending = group ? &t->signal->shared_pending : &t->pending; |
1da177e4c Linux-2.6.12-rc2 |
1026 |
/* |
2acb024d5 signals: consolid... |
1027 1028 1029 1030 |
* 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. */ |
7e695a5ef signals: fold sig... |
1031 |
if (legacy_queue(pending, sig)) |
2acb024d5 signals: consolid... |
1032 |
return 0; |
fba2afaae signal/timer/even... |
1033 |
/* |
1da177e4c Linux-2.6.12-rc2 |
1034 1035 1036 |
* fast-pathed signals for kernel-internal things like SIGSTOP * or SIGKILL. */ |
b67a1b9e4 [PATCH] remove ha... |
1037 |
if (info == SEND_SIG_FORCED) |
1da177e4c Linux-2.6.12-rc2 |
1038 |
goto out_set; |
5aba085ed kernel/signal.c: ... |
1039 1040 1041 1042 1043 1044 1045 1046 1047 |
/* * 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... |
1048 1049 1050 1051 |
if (sig < SIGRTMIN) override_rlimit = (is_si_special(info) || info->si_code >= 0); else override_rlimit = 0; |
f84d49b21 signal: Print war... |
1052 |
q = __sigqueue_alloc(sig, t, GFP_ATOMIC | __GFP_NOTRACK_FALSE_POSITIVE, |
7a0aeb14e signal: fix __sen... |
1053 |
override_rlimit); |
1da177e4c Linux-2.6.12-rc2 |
1054 |
if (q) { |
2ca3515aa signals: change s... |
1055 |
list_add_tail(&q->list, &pending->list); |
1da177e4c Linux-2.6.12-rc2 |
1056 |
switch ((unsigned long) info) { |
b67a1b9e4 [PATCH] remove ha... |
1057 |
case (unsigned long) SEND_SIG_NOINFO: |
1da177e4c Linux-2.6.12-rc2 |
1058 1059 1060 |
q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_USER; |
9cd4fd104 SEND_SIG_NOINFO: ... |
1061 |
q->info.si_pid = task_tgid_nr_ns(current, |
09bca05c9 SEND_SIG_NOINFO: ... |
1062 |
task_active_pid_ns(t)); |
76aac0e9a CRED: Wrap task c... |
1063 |
q->info.si_uid = current_uid(); |
1da177e4c Linux-2.6.12-rc2 |
1064 |
break; |
b67a1b9e4 [PATCH] remove ha... |
1065 |
case (unsigned long) SEND_SIG_PRIV: |
1da177e4c Linux-2.6.12-rc2 |
1066 1067 1068 1069 1070 1071 1072 1073 |
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:... |
1074 1075 |
if (from_ancestor_ns) q->info.si_pid = 0; |
1da177e4c Linux-2.6.12-rc2 |
1076 1077 |
break; } |
6b550f949 user namespace: m... |
1078 1079 |
userns_fixup_signal_uid(&q->info, t); |
621d31219 [PATCH] cleanup t... |
1080 |
} else if (!is_si_special(info)) { |
ba005e1f4 tracepoint: Add s... |
1081 1082 1083 1084 1085 1086 1087 |
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(). */ trace_signal_overflow_fail(sig, group, info); |
1da177e4c Linux-2.6.12-rc2 |
1088 |
return -EAGAIN; |
ba005e1f4 tracepoint: Add s... |
1089 1090 1091 1092 1093 1094 1095 |
} else { /* * This is a silent loss of information. We still * send the signal, but the *info bits are lost. */ trace_signal_lose_info(sig, group, info); } |
1da177e4c Linux-2.6.12-rc2 |
1096 1097 1098 |
} out_set: |
53c30337f signals: send_sig... |
1099 |
signalfd_notify(t, sig); |
2ca3515aa signals: change s... |
1100 |
sigaddset(&pending->signal, sig); |
4cd4b6d4e signals: fold com... |
1101 1102 |
complete_signal(sig, t, group); return 0; |
1da177e4c Linux-2.6.12-rc2 |
1103 |
} |
7978b567d signals: add from... |
1104 1105 1106 |
static int send_signal(int sig, struct siginfo *info, struct task_struct *t, int group) { |
921cf9f63 signals: protect ... |
1107 1108 1109 |
int from_ancestor_ns = 0; #ifdef CONFIG_PID_NS |
dd34200ad signals: send_sig... |
1110 1111 |
from_ancestor_ns = si_fromuser(info) && !task_pid_nr_ns(current, task_active_pid_ns(t)); |
921cf9f63 signals: protect ... |
1112 1113 1114 |
#endif return __send_signal(sig, info, t, group, from_ancestor_ns); |
7978b567d signals: add from... |
1115 |
} |
45807a1df vdso: print fatal... |
1116 1117 1118 1119 |
static void print_fatal_signal(struct pt_regs *regs, int signr) { printk("%s/%d: potentially unexpected fatal signal %d. ", |
ba25f9dcc Use helpers to ob... |
1120 |
current->comm, task_pid_nr(current), signr); |
45807a1df vdso: print fatal... |
1121 |
|
ca5cd877a x86 merge fallout... |
1122 |
#if defined(__i386__) && !defined(__arch_um__) |
65ea5b034 x86: rename the s... |
1123 |
printk("code at %08lx: ", regs->ip); |
45807a1df vdso: print fatal... |
1124 1125 1126 1127 |
{ int i; for (i = 0; i < 16; i++) { unsigned char insn; |
b45c6e76b kernel/signal.c: ... |
1128 1129 |
if (get_user(insn, (unsigned char *)(regs->ip + i))) break; |
45807a1df vdso: print fatal... |
1130 1131 1132 1133 1134 1135 |
printk("%02x ", insn); } } #endif printk(" "); |
3a9f84d35 signals, debug: f... |
1136 |
preempt_disable(); |
45807a1df vdso: print fatal... |
1137 |
show_regs(regs); |
3a9f84d35 signals, debug: f... |
1138 |
preempt_enable(); |
45807a1df vdso: print fatal... |
1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 |
} 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 |
1149 |
|
4cd4b6d4e signals: fold com... |
1150 1151 1152 1153 1154 |
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 |
1155 1156 1157 |
static int specific_send_sig_info(int sig, struct siginfo *info, struct task_struct *t) { |
4cd4b6d4e signals: fold com... |
1158 |
return send_signal(sig, info, t, 0); |
1da177e4c Linux-2.6.12-rc2 |
1159 |
} |
4a30debfb signals: introduc... |
1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 |
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 |
1173 1174 1175 |
/* * 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... |
1176 1177 1178 1179 1180 |
* * 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... |
1181 1182 |
* 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 |
1183 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
1184 1185 1186 1187 |
int force_sig_info(int sig, struct siginfo *info, struct task_struct *t) { unsigned long int flags; |
ae74c3b69 Fix force_sig_inf... |
1188 1189 |
int ret, blocked, ignored; struct k_sigaction *action; |
1da177e4c Linux-2.6.12-rc2 |
1190 1191 |
spin_lock_irqsave(&t->sighand->siglock, flags); |
ae74c3b69 Fix force_sig_inf... |
1192 1193 1194 1195 1196 1197 1198 |
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... |
1199 |
recalc_sigpending_and_wake(t); |
ae74c3b69 Fix force_sig_inf... |
1200 |
} |
1da177e4c Linux-2.6.12-rc2 |
1201 |
} |
80fe728d5 signals: allow th... |
1202 1203 |
if (action->sa.sa_handler == SIG_DFL) t->signal->flags &= ~SIGNAL_UNKILLABLE; |
1da177e4c Linux-2.6.12-rc2 |
1204 1205 1206 1207 1208 |
ret = specific_send_sig_info(sig, info, t); spin_unlock_irqrestore(&t->sighand->siglock, flags); return ret; } |
1da177e4c Linux-2.6.12-rc2 |
1209 1210 1211 |
/* * Nuke all other threads in the group. */ |
09faef11d exit: change zap_... |
1212 |
int zap_other_threads(struct task_struct *p) |
1da177e4c Linux-2.6.12-rc2 |
1213 |
{ |
09faef11d exit: change zap_... |
1214 1215 |
struct task_struct *t = p; int count = 0; |
1da177e4c Linux-2.6.12-rc2 |
1216 |
|
1da177e4c Linux-2.6.12-rc2 |
1217 |
p->signal->group_stop_count = 0; |
09faef11d exit: change zap_... |
1218 |
while_each_thread(p, t) { |
6dfca3298 job control: make... |
1219 |
task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); |
09faef11d exit: change zap_... |
1220 1221 1222 |
count++; /* Don't bother with already dead threads */ |
1da177e4c Linux-2.6.12-rc2 |
1223 1224 |
if (t->exit_state) continue; |
1da177e4c Linux-2.6.12-rc2 |
1225 |
sigaddset(&t->pending.signal, SIGKILL); |
1da177e4c Linux-2.6.12-rc2 |
1226 1227 |
signal_wake_up(t, 1); } |
09faef11d exit: change zap_... |
1228 1229 |
return count; |
1da177e4c Linux-2.6.12-rc2 |
1230 |
} |
b8ed374e2 signals: annotate... |
1231 1232 |
struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, unsigned long *flags) |
f63ee72e0 [PATCH] introduce... |
1233 1234 1235 1236 |
{ struct sighand_struct *sighand; for (;;) { |
a841796f1 signal: align __l... |
1237 1238 |
local_irq_save(*flags); rcu_read_lock(); |
f63ee72e0 [PATCH] introduce... |
1239 |
sighand = rcu_dereference(tsk->sighand); |
a841796f1 signal: align __l... |
1240 1241 1242 |
if (unlikely(sighand == NULL)) { rcu_read_unlock(); local_irq_restore(*flags); |
f63ee72e0 [PATCH] introduce... |
1243 |
break; |
a841796f1 signal: align __l... |
1244 |
} |
f63ee72e0 [PATCH] introduce... |
1245 |
|
a841796f1 signal: align __l... |
1246 1247 1248 |
spin_lock(&sighand->siglock); if (likely(sighand == tsk->sighand)) { rcu_read_unlock(); |
f63ee72e0 [PATCH] introduce... |
1249 |
break; |
a841796f1 signal: align __l... |
1250 1251 1252 1253 |
} spin_unlock(&sighand->siglock); rcu_read_unlock(); local_irq_restore(*flags); |
f63ee72e0 [PATCH] introduce... |
1254 1255 1256 1257 |
} return sighand; } |
c69e8d9c0 CRED: Use RCU to ... |
1258 1259 |
/* * send signal info to all the members of a group |
c69e8d9c0 CRED: Use RCU to ... |
1260 |
*/ |
1da177e4c Linux-2.6.12-rc2 |
1261 1262 |
int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { |
694f690d2 CRED: Fix RCU war... |
1263 1264 1265 1266 1267 |
int ret; rcu_read_lock(); ret = check_kill_permission(sig, info, p); rcu_read_unlock(); |
f63ee72e0 [PATCH] introduce... |
1268 |
|
4a30debfb signals: introduc... |
1269 1270 |
if (!ret && sig) ret = do_send_sig_info(sig, info, p, true); |
1da177e4c Linux-2.6.12-rc2 |
1271 1272 1273 1274 1275 |
return ret; } /* |
146a505d4 Get rid of the ki... |
1276 |
* __kill_pgrp_info() sends a signal to a process group: this is what the tty |
1da177e4c Linux-2.6.12-rc2 |
1277 |
* control characters do (^C, ^Z etc) |
c69e8d9c0 CRED: Use RCU to ... |
1278 |
* - the caller must hold at least a readlock on tasklist_lock |
1da177e4c Linux-2.6.12-rc2 |
1279 |
*/ |
c4b92fc11 [PATCH] pid: impl... |
1280 |
int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp) |
1da177e4c Linux-2.6.12-rc2 |
1281 1282 1283 |
{ struct task_struct *p = NULL; int retval, success; |
1da177e4c Linux-2.6.12-rc2 |
1284 1285 |
success = 0; retval = -ESRCH; |
c4b92fc11 [PATCH] pid: impl... |
1286 |
do_each_pid_task(pgrp, PIDTYPE_PGID, p) { |
1da177e4c Linux-2.6.12-rc2 |
1287 1288 1289 |
int err = group_send_sig_info(sig, info, p); success |= !err; retval = err; |
c4b92fc11 [PATCH] pid: impl... |
1290 |
} while_each_pid_task(pgrp, PIDTYPE_PGID, p); |
1da177e4c Linux-2.6.12-rc2 |
1291 1292 |
return success ? 0 : retval; } |
c4b92fc11 [PATCH] pid: impl... |
1293 |
int kill_pid_info(int sig, struct siginfo *info, struct pid *pid) |
1da177e4c Linux-2.6.12-rc2 |
1294 |
{ |
d36174bc2 uglify kill_pid_i... |
1295 |
int error = -ESRCH; |
1da177e4c Linux-2.6.12-rc2 |
1296 |
struct task_struct *p; |
e56d09031 [PATCH] RCU signa... |
1297 |
rcu_read_lock(); |
d36174bc2 uglify kill_pid_i... |
1298 |
retry: |
c4b92fc11 [PATCH] pid: impl... |
1299 |
p = pid_task(pid, PIDTYPE_PID); |
d36174bc2 uglify kill_pid_i... |
1300 |
if (p) { |
1da177e4c Linux-2.6.12-rc2 |
1301 |
error = group_send_sig_info(sig, info, p); |
d36174bc2 uglify kill_pid_i... |
1302 1303 1304 1305 1306 1307 1308 1309 1310 |
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... |
1311 |
rcu_read_unlock(); |
6ca25b551 kill_pid_info: do... |
1312 |
|
1da177e4c Linux-2.6.12-rc2 |
1313 1314 |
return error; } |
5aba085ed kernel/signal.c: ... |
1315 |
int kill_proc_info(int sig, struct siginfo *info, pid_t pid) |
c4b92fc11 [PATCH] pid: impl... |
1316 1317 1318 |
{ int error; rcu_read_lock(); |
b488893a3 pid namespaces: c... |
1319 |
error = kill_pid_info(sig, info, find_vpid(pid)); |
c4b92fc11 [PATCH] pid: impl... |
1320 1321 1322 |
rcu_read_unlock(); return error; } |
d178bc3a7 user namespace: u... |
1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 |
static int kill_as_cred_perm(const struct cred *cred, struct task_struct *target) { const struct cred *pcred = __task_cred(target); if (cred->user_ns != pcred->user_ns) return 0; if (cred->euid != pcred->suid && cred->euid != pcred->uid && cred->uid != pcred->suid && cred->uid != pcred->uid) return 0; return 1; } |
2425c08b3 [PATCH] usb: fixu... |
1334 |
/* like kill_pid_info(), but doesn't use uid/euid of "current" */ |
d178bc3a7 user namespace: u... |
1335 1336 |
int kill_pid_info_as_cred(int sig, struct siginfo *info, struct pid *pid, const struct cred *cred, u32 secid) |
46113830a [PATCH] Fix signa... |
1337 1338 1339 |
{ int ret = -EINVAL; struct task_struct *p; |
14d8c9f3c signal: Fix racy ... |
1340 |
unsigned long flags; |
46113830a [PATCH] Fix signa... |
1341 1342 1343 |
if (!valid_signal(sig)) return ret; |
14d8c9f3c signal: Fix racy ... |
1344 |
rcu_read_lock(); |
2425c08b3 [PATCH] usb: fixu... |
1345 |
p = pid_task(pid, PIDTYPE_PID); |
46113830a [PATCH] Fix signa... |
1346 1347 1348 1349 |
if (!p) { ret = -ESRCH; goto out_unlock; } |
d178bc3a7 user namespace: u... |
1350 |
if (si_fromuser(info) && !kill_as_cred_perm(cred, p)) { |
46113830a [PATCH] Fix signa... |
1351 1352 1353 |
ret = -EPERM; goto out_unlock; } |
8f95dc58d [PATCH] SELinux: ... |
1354 1355 1356 |
ret = security_task_kill(p, info, sig, secid); if (ret) goto out_unlock; |
14d8c9f3c signal: Fix racy ... |
1357 1358 1359 1360 1361 1362 1363 |
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... |
1364 1365 |
} out_unlock: |
14d8c9f3c signal: Fix racy ... |
1366 |
rcu_read_unlock(); |
46113830a [PATCH] Fix signa... |
1367 1368 |
return ret; } |
d178bc3a7 user namespace: u... |
1369 |
EXPORT_SYMBOL_GPL(kill_pid_info_as_cred); |
1da177e4c Linux-2.6.12-rc2 |
1370 1371 1372 1373 1374 1375 1376 |
/* * 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: ... |
1377 |
static int kill_something_info(int sig, struct siginfo *info, pid_t pid) |
1da177e4c Linux-2.6.12-rc2 |
1378 |
{ |
8d42db189 [PATCH] signal: r... |
1379 |
int ret; |
d5df763b8 Clean up the kill... |
1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 |
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 |
1393 1394 |
int retval = 0, count = 0; struct task_struct * p; |
1da177e4c Linux-2.6.12-rc2 |
1395 |
for_each_process(p) { |
d25141a81 'kill sig -1' mus... |
1396 1397 |
if (task_pid_vnr(p) > 1 && !same_thread_group(p, current)) { |
1da177e4c Linux-2.6.12-rc2 |
1398 1399 1400 1401 1402 1403 |
int err = group_send_sig_info(sig, info, p); ++count; if (err != -EPERM) retval = err; } } |
8d42db189 [PATCH] signal: r... |
1404 |
ret = count ? retval : -ESRCH; |
1da177e4c Linux-2.6.12-rc2 |
1405 |
} |
d5df763b8 Clean up the kill... |
1406 |
read_unlock(&tasklist_lock); |
8d42db189 [PATCH] signal: r... |
1407 |
return ret; |
1da177e4c Linux-2.6.12-rc2 |
1408 1409 1410 1411 1412 |
} /* * These are for backward compatibility with the rest of the kernel source. */ |
5aba085ed kernel/signal.c: ... |
1413 |
int send_sig_info(int sig, struct siginfo *info, struct task_struct *p) |
1da177e4c Linux-2.6.12-rc2 |
1414 |
{ |
1da177e4c Linux-2.6.12-rc2 |
1415 1416 1417 1418 |
/* * Make sure legacy kernel users don't send in bad values * (normal paths check this in check_kill_permission). */ |
7ed20e1ad [PATCH] convert t... |
1419 |
if (!valid_signal(sig)) |
1da177e4c Linux-2.6.12-rc2 |
1420 |
return -EINVAL; |
4a30debfb signals: introduc... |
1421 |
return do_send_sig_info(sig, info, p, false); |
1da177e4c Linux-2.6.12-rc2 |
1422 |
} |
b67a1b9e4 [PATCH] remove ha... |
1423 1424 |
#define __si_special(priv) \ ((priv) ? SEND_SIG_PRIV : SEND_SIG_NOINFO) |
1da177e4c Linux-2.6.12-rc2 |
1425 1426 1427 |
int send_sig(int sig, struct task_struct *p, int priv) { |
b67a1b9e4 [PATCH] remove ha... |
1428 |
return send_sig_info(sig, __si_special(priv), p); |
1da177e4c Linux-2.6.12-rc2 |
1429 |
} |
1da177e4c Linux-2.6.12-rc2 |
1430 1431 1432 |
void force_sig(int sig, struct task_struct *p) { |
b67a1b9e4 [PATCH] remove ha... |
1433 |
force_sig_info(sig, SEND_SIG_PRIV, p); |
1da177e4c Linux-2.6.12-rc2 |
1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 |
} /* * 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... |
1454 1455 |
int kill_pgrp(struct pid *pid, int sig, int priv) { |
146a505d4 Get rid of the ki... |
1456 1457 1458 1459 1460 1461 1462 |
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... |
1463 1464 1465 1466 1467 1468 1469 1470 |
} 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 |
1471 1472 1473 1474 |
/* * 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: ... |
1475 |
* expirations or I/O completions". In the case of POSIX Timers |
1da177e4c Linux-2.6.12-rc2 |
1476 1477 1478 1479 |
* 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 |
1480 1481 |
struct sigqueue *sigqueue_alloc(void) { |
f84d49b21 signal: Print war... |
1482 |
struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0); |
1da177e4c Linux-2.6.12-rc2 |
1483 |
|
f84d49b21 signal: Print war... |
1484 |
if (q) |
1da177e4c Linux-2.6.12-rc2 |
1485 |
q->flags |= SIGQUEUE_PREALLOC; |
f84d49b21 signal: Print war... |
1486 1487 |
return q; |
1da177e4c Linux-2.6.12-rc2 |
1488 1489 1490 1491 1492 |
} void sigqueue_free(struct sigqueue *q) { unsigned long flags; |
60187d270 sigqueue_free: fi... |
1493 |
spinlock_t *lock = ¤t->sighand->siglock; |
1da177e4c Linux-2.6.12-rc2 |
1494 1495 |
BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); /* |
c8e85b4f4 posix timers: sig... |
1496 1497 |
* We must hold ->siglock while testing q->list * to serialize with collect_signal() or with |
da7978b03 signals: fix sigq... |
1498 |
* __exit_signal()->flush_sigqueue(). |
1da177e4c Linux-2.6.12-rc2 |
1499 |
*/ |
60187d270 sigqueue_free: fi... |
1500 |
spin_lock_irqsave(lock, flags); |
c8e85b4f4 posix timers: sig... |
1501 1502 1503 1504 1505 |
q->flags &= ~SIGQUEUE_PREALLOC; /* * If it is queued it will be freed when dequeued, * like the "regular" sigqueue. */ |
60187d270 sigqueue_free: fi... |
1506 |
if (!list_empty(&q->list)) |
c8e85b4f4 posix timers: sig... |
1507 |
q = NULL; |
60187d270 sigqueue_free: fi... |
1508 |
spin_unlock_irqrestore(lock, flags); |
c8e85b4f4 posix timers: sig... |
1509 1510 |
if (q) __sigqueue_free(q); |
1da177e4c Linux-2.6.12-rc2 |
1511 |
} |
ac5c21538 signals: join sen... |
1512 |
int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group) |
9e3bd6c3f signals: consolid... |
1513 |
{ |
e62e6650e signals: unify se... |
1514 |
int sig = q->info.si_signo; |
2ca3515aa signals: change s... |
1515 |
struct sigpending *pending; |
e62e6650e signals: unify se... |
1516 1517 |
unsigned long flags; int ret; |
2ca3515aa signals: change s... |
1518 |
|
4cd4b6d4e signals: fold com... |
1519 |
BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); |
e62e6650e signals: unify se... |
1520 1521 1522 1523 |
ret = -1; if (!likely(lock_task_sighand(t, &flags))) goto ret; |
7e695a5ef signals: fold sig... |
1524 |
ret = 1; /* the signal is ignored */ |
921cf9f63 signals: protect ... |
1525 |
if (!prepare_signal(sig, t, 0)) |
e62e6650e signals: unify se... |
1526 1527 1528 |
goto out; ret = 0; |
9e3bd6c3f signals: consolid... |
1529 1530 1531 1532 1533 |
if (unlikely(!list_empty(&q->list))) { /* * If an SI_TIMER entry is already queue just increment * the overrun count. */ |
9e3bd6c3f signals: consolid... |
1534 1535 |
BUG_ON(q->info.si_code != SI_TIMER); q->info.si_overrun++; |
e62e6650e signals: unify se... |
1536 |
goto out; |
9e3bd6c3f signals: consolid... |
1537 |
} |
ba661292a posix-timers: fix... |
1538 |
q->info.si_overrun = 0; |
9e3bd6c3f signals: consolid... |
1539 |
|
9e3bd6c3f signals: consolid... |
1540 |
signalfd_notify(t, sig); |
2ca3515aa signals: change s... |
1541 |
pending = group ? &t->signal->shared_pending : &t->pending; |
9e3bd6c3f signals: consolid... |
1542 1543 |
list_add_tail(&q->list, &pending->list); sigaddset(&pending->signal, sig); |
4cd4b6d4e signals: fold com... |
1544 |
complete_signal(sig, t, group); |
e62e6650e signals: unify se... |
1545 1546 1547 1548 |
out: 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; |
1da177e4c Linux-2.6.12-rc2 |
1563 1564 1565 1566 |
BUG_ON(sig == -1); /* do_notify_parent_cldstop should have been called instead. */ |
e1abb39c6 signal: Use task_... |
1567 |
BUG_ON(task_is_stopped_or_traced(tsk)); |
1da177e4c Linux-2.6.12-rc2 |
1568 |
|
d21142ece ptrace: kill task... |
1569 |
BUG_ON(!tsk->ptrace && |
1da177e4c Linux-2.6.12-rc2 |
1570 1571 1572 1573 |
(tsk->group_leader != tsk || !thread_group_empty(tsk))); info.si_signo = sig; info.si_errno = 0; |
b488893a3 pid namespaces: c... |
1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 |
/* * we are under tasklist_lock here so our parent is tied to * us and cannot exit and release its namespace. * * the only it can is to switch its nsproxy with sys_unshare, * bu uncharing pid namespaces is not allowed, so we'll always * see relevant namespace * * 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(); info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns); |
6b550f949 user namespace: m... |
1588 1589 |
info.si_uid = map_cred_ns(__task_cred(tsk), task_cred_xxx(tsk->parent, user_ns)); |
b488893a3 pid namespaces: c... |
1590 |
rcu_read_unlock(); |
648616343 [S390] cputime: a... |
1591 1592 |
info.si_utime = cputime_to_clock_t(tsk->utime + tsk->signal->utime); info.si_stime = cputime_to_clock_t(tsk->stime + tsk->signal->stime); |
1da177e4c Linux-2.6.12-rc2 |
1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 |
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... |
1606 |
if (!tsk->ptrace && sig == SIGCHLD && |
1da177e4c Linux-2.6.12-rc2 |
1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 |
(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... |
1624 |
autoreap = true; |
1da177e4c Linux-2.6.12-rc2 |
1625 |
if (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) |
53c8f9f19 make do_notify_pa... |
1626 |
sig = 0; |
1da177e4c Linux-2.6.12-rc2 |
1627 |
} |
53c8f9f19 make do_notify_pa... |
1628 |
if (valid_signal(sig) && sig) |
1da177e4c Linux-2.6.12-rc2 |
1629 1630 1631 |
__group_send_sig_info(sig, &info, tsk->parent); __wake_up_parent(tsk, tsk->parent); spin_unlock_irqrestore(&psig->siglock, flags); |
2b2a1ff64 tracehook: death |
1632 |
|
53c8f9f19 make do_notify_pa... |
1633 |
return autoreap; |
1da177e4c Linux-2.6.12-rc2 |
1634 |
} |
75b95953a job control: Add ... |
1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 |
/** * 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 |
1650 1651 1652 |
{ struct siginfo info; unsigned long flags; |
bc505a478 [PATCH] do_notify... |
1653 |
struct task_struct *parent; |
1da177e4c Linux-2.6.12-rc2 |
1654 |
struct sighand_struct *sighand; |
75b95953a job control: Add ... |
1655 |
if (for_ptracer) { |
bc505a478 [PATCH] do_notify... |
1656 |
parent = tsk->parent; |
75b95953a job control: Add ... |
1657 |
} else { |
bc505a478 [PATCH] do_notify... |
1658 1659 1660 |
tsk = tsk->group_leader; parent = tsk->real_parent; } |
1da177e4c Linux-2.6.12-rc2 |
1661 1662 |
info.si_signo = SIGCHLD; info.si_errno = 0; |
b488893a3 pid namespaces: c... |
1663 |
/* |
5aba085ed kernel/signal.c: ... |
1664 |
* see comment in do_notify_parent() about the following 4 lines |
b488893a3 pid namespaces: c... |
1665 1666 |
*/ rcu_read_lock(); |
d92656633 ptrace: do_notify... |
1667 |
info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns); |
6b550f949 user namespace: m... |
1668 1669 |
info.si_uid = map_cred_ns(__task_cred(tsk), task_cred_xxx(parent, user_ns)); |
b488893a3 pid namespaces: c... |
1670 |
rcu_read_unlock(); |
d8878ba3f signals: make sig... |
1671 1672 |
info.si_utime = cputime_to_clock_t(tsk->utime); info.si_stime = cputime_to_clock_t(tsk->stime); |
1da177e4c Linux-2.6.12-rc2 |
1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 |
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:... |
1700 1701 |
static inline int may_ptrace_stop(void) { |
d21142ece ptrace: kill task... |
1702 |
if (!likely(current->ptrace)) |
d5f70c00a [PATCH] coredump:... |
1703 |
return 0; |
d5f70c00a [PATCH] coredump:... |
1704 1705 1706 1707 1708 1709 |
/* * 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... |
1710 |
* ->siglock we must see ->core_state != NULL. Otherwise it |
d5f70c00a [PATCH] coredump:... |
1711 1712 |
* is safe to enter schedule(). */ |
999d9fc16 coredump: move mm... |
1713 |
if (unlikely(current->mm->core_state) && |
d5f70c00a [PATCH] coredump:... |
1714 1715 1716 1717 1718 |
unlikely(current->mm == current->parent->mm)) return 0; return 1; } |
1da177e4c Linux-2.6.12-rc2 |
1719 |
/* |
5aba085ed kernel/signal.c: ... |
1720 |
* Return non-zero if there is a SIGKILL that should be waking us up. |
1a669c2f1 Add arch_ptrace_stop |
1721 1722 1723 1724 |
* Called with the siglock held. */ static int sigkill_pending(struct task_struct *tsk) { |
3d749b9e6 ptrace: simplify ... |
1725 1726 |
return sigismember(&tsk->pending.signal, SIGKILL) || sigismember(&tsk->signal->shared_pending.signal, SIGKILL); |
1a669c2f1 Add arch_ptrace_stop |
1727 1728 1729 |
} /* |
1da177e4c Linux-2.6.12-rc2 |
1730 1731 1732 1733 1734 1735 1736 |
* 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 ... |
1737 1738 |
* 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 |
1739 |
*/ |
fe1bc6a09 ptrace: Add @why ... |
1740 |
static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info) |
b84011508 signals: annotate... |
1741 1742 |
__releases(¤t->sighand->siglock) __acquires(¤t->sighand->siglock) |
1da177e4c Linux-2.6.12-rc2 |
1743 |
{ |
ceb6bd67f job control: Noti... |
1744 |
bool gstop_done = false; |
1a669c2f1 Add arch_ptrace_stop |
1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 |
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 ... |
1760 1761 |
if (sigkill_pending(current)) return; |
1a669c2f1 Add arch_ptrace_stop |
1762 |
} |
1da177e4c Linux-2.6.12-rc2 |
1763 |
/* |
81be24b8c ptrace: relocate ... |
1764 1765 1766 1767 1768 |
* 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 |
1769 |
*/ |
81be24b8c ptrace: relocate ... |
1770 |
set_current_state(TASK_TRACED); |
1da177e4c Linux-2.6.12-rc2 |
1771 1772 1773 |
current->last_siginfo = info; current->exit_code = exit_code; |
d79fdd6d9 ptrace: Clean tra... |
1774 |
/* |
0ae8ce1c8 ptrace: Participa... |
1775 1776 |
* 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... |
1777 1778 1779 |
* 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... |
1780 |
*/ |
a8f072c1d job control: rena... |
1781 |
if (why == CLD_STOPPED && (current->jobctl & JOBCTL_STOP_PENDING)) |
ceb6bd67f job control: Noti... |
1782 |
gstop_done = task_participate_group_stop(current); |
d79fdd6d9 ptrace: Clean tra... |
1783 |
|
fb1d910c1 ptrace: implement... |
1784 |
/* any trap clears pending STOP trap, STOP trap clears NOTIFY */ |
73ddff2be job control: intr... |
1785 |
task_clear_jobctl_pending(current, JOBCTL_TRAP_STOP); |
fb1d910c1 ptrace: implement... |
1786 1787 |
if (info && info->si_code >> 8 == PTRACE_EVENT_STOP) task_clear_jobctl_pending(current, JOBCTL_TRAP_NOTIFY); |
73ddff2be job control: intr... |
1788 |
|
81be24b8c ptrace: relocate ... |
1789 |
/* entering a trap, clear TRAPPING */ |
a8f072c1d job control: rena... |
1790 |
task_clear_jobctl_trapping(current); |
d79fdd6d9 ptrace: Clean tra... |
1791 |
|
1da177e4c Linux-2.6.12-rc2 |
1792 1793 |
spin_unlock_irq(¤t->sighand->siglock); read_lock(&tasklist_lock); |
3d749b9e6 ptrace: simplify ... |
1794 |
if (may_ptrace_stop()) { |
ceb6bd67f job control: Noti... |
1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 |
/* * 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... |
1806 |
if (gstop_done && ptrace_reparented(current)) |
ceb6bd67f job control: Noti... |
1807 |
do_notify_parent_cldstop(current, false, why); |
53da1d945 fix ptrace slowness |
1808 1809 1810 1811 1812 1813 1814 |
/* * 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 |
1815 |
read_unlock(&tasklist_lock); |
53da1d945 fix ptrace slowness |
1816 |
preempt_enable_no_resched(); |
1da177e4c Linux-2.6.12-rc2 |
1817 1818 1819 1820 |
schedule(); } else { /* * By the time we got the lock, our tracer went away. |
6405f7f46 ptrace_stop: fix ... |
1821 |
* Don't drop the lock yet, another tracer may come. |
ceb6bd67f job control: Noti... |
1822 1823 1824 |
* * If @gstop_done, the ptracer went away between group stop * completion and here. During detach, it would have set |
a8f072c1d job control: rena... |
1825 1826 1827 |
* 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 |
1828 |
*/ |
ceb6bd67f job control: Noti... |
1829 1830 |
if (gstop_done) do_notify_parent_cldstop(current, false, why); |
6405f7f46 ptrace_stop: fix ... |
1831 |
__set_current_state(TASK_RUNNING); |
20686a309 ptrace_stop: fix ... |
1832 1833 |
if (clear_code) current->exit_code = 0; |
6405f7f46 ptrace_stop: fix ... |
1834 |
read_unlock(&tasklist_lock); |
1da177e4c Linux-2.6.12-rc2 |
1835 1836 1837 |
} /* |
13b1c3d4b freezer vs stoppe... |
1838 1839 1840 1841 1842 1843 1844 |
* While in TASK_TRACED, we were considered "frozen enough". * Now that we woke up, it's crucial if we're supposed to be * frozen that we freeze now before running anything substantial. */ try_to_freeze(); /* |
1da177e4c Linux-2.6.12-rc2 |
1845 1846 1847 1848 1849 1850 |
* 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... |
1851 1852 |
/* LISTENING can be set only during STOP traps, clear it */ current->jobctl &= ~JOBCTL_LISTENING; |
1da177e4c Linux-2.6.12-rc2 |
1853 1854 1855 |
/* * 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... |
1856 |
* This sets TIF_SIGPENDING, but never clears it. |
1da177e4c Linux-2.6.12-rc2 |
1857 |
*/ |
b74d0deb9 Restrict clearing... |
1858 |
recalc_sigpending_tsk(current); |
1da177e4c Linux-2.6.12-rc2 |
1859 |
} |
3544d72a0 ptrace: implement... |
1860 |
static void ptrace_do_notify(int signr, int exit_code, int why) |
1da177e4c Linux-2.6.12-rc2 |
1861 1862 |
{ siginfo_t info; |
1da177e4c Linux-2.6.12-rc2 |
1863 |
memset(&info, 0, sizeof info); |
3544d72a0 ptrace: implement... |
1864 |
info.si_signo = signr; |
1da177e4c Linux-2.6.12-rc2 |
1865 |
info.si_code = exit_code; |
b488893a3 pid namespaces: c... |
1866 |
info.si_pid = task_pid_vnr(current); |
76aac0e9a CRED: Wrap task c... |
1867 |
info.si_uid = current_uid(); |
1da177e4c Linux-2.6.12-rc2 |
1868 1869 |
/* Let the debugger run. */ |
3544d72a0 ptrace: implement... |
1870 1871 1872 1873 1874 1875 |
ptrace_stop(exit_code, why, 1, &info); } void ptrace_notify(int exit_code) { BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP); |
1da177e4c Linux-2.6.12-rc2 |
1876 |
spin_lock_irq(¤t->sighand->siglock); |
3544d72a0 ptrace: implement... |
1877 |
ptrace_do_notify(SIGTRAP, exit_code, CLD_TRAPPED); |
1da177e4c Linux-2.6.12-rc2 |
1878 1879 |
spin_unlock_irq(¤t->sighand->siglock); } |
73ddff2be job control: intr... |
1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 |
/** * 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 |
1901 |
*/ |
73ddff2be job control: intr... |
1902 1903 |
static bool do_signal_stop(int signr) __releases(¤t->sighand->siglock) |
1da177e4c Linux-2.6.12-rc2 |
1904 1905 |
{ struct signal_struct *sig = current->signal; |
1da177e4c Linux-2.6.12-rc2 |
1906 |
|
a8f072c1d job control: rena... |
1907 1908 |
if (!(current->jobctl & JOBCTL_STOP_PENDING)) { unsigned int gstop = JOBCTL_STOP_PENDING | JOBCTL_STOP_CONSUME; |
f558b7e40 remove handle_gro... |
1909 |
struct task_struct *t; |
a8f072c1d job control: rena... |
1910 1911 |
/* signr will be recorded in task->jobctl for retries */ WARN_ON_ONCE(signr & ~JOBCTL_STOP_SIGMASK); |
d79fdd6d9 ptrace: Clean tra... |
1912 |
|
a8f072c1d job control: rena... |
1913 |
if (!likely(current->jobctl & JOBCTL_STOP_DEQUEUED) || |
573cf9ad7 signals: do_signa... |
1914 |
unlikely(signal_group_exit(sig))) |
73ddff2be job control: intr... |
1915 |
return false; |
1da177e4c Linux-2.6.12-rc2 |
1916 |
/* |
408a37de6 job control: Don'... |
1917 1918 1919 1920 1921 1922 1923 |
* 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... |
1924 1925 |
* cause two group stops when !ptraced. That is why we * also check !task_is_stopped(t) below. |
408a37de6 job control: Don'... |
1926 1927 1928 1929 1930 1931 1932 1933 |
* * 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 |
1934 |
*/ |
408a37de6 job control: Don'... |
1935 1936 |
if (!(sig->flags & SIGNAL_STOP_STOPPED)) sig->group_exit_code = signr; |
1da177e4c Linux-2.6.12-rc2 |
1937 |
|
7dd3db54e job control: intr... |
1938 1939 1940 1941 |
sig->group_stop_count = 0; if (task_set_jobctl_pending(current, signr | gstop)) sig->group_stop_count++; |
1da177e4c Linux-2.6.12-rc2 |
1942 |
|
d79fdd6d9 ptrace: Clean tra... |
1943 1944 |
for (t = next_thread(current); t != current; t = next_thread(t)) { |
1da177e4c Linux-2.6.12-rc2 |
1945 |
/* |
a122b341b [PATCH] do_signal... |
1946 1947 1948 |
* 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 |
1949 |
*/ |
7dd3db54e job control: intr... |
1950 1951 |
if (!task_is_stopped(t) && task_set_jobctl_pending(t, signr | gstop)) { |
ae6d2ed7b signals: tracehoo... |
1952 |
sig->group_stop_count++; |
fb1d910c1 ptrace: implement... |
1953 1954 1955 1956 |
if (likely(!(t->ptrace & PT_SEIZED))) signal_wake_up(t, 0); else ptrace_trap_notify(t); |
a122b341b [PATCH] do_signal... |
1957 |
} |
d79fdd6d9 ptrace: Clean tra... |
1958 |
} |
1da177e4c Linux-2.6.12-rc2 |
1959 |
} |
73ddff2be job control: intr... |
1960 |
|
d21142ece ptrace: kill task... |
1961 |
if (likely(!current->ptrace)) { |
5224fa366 ptrace: Make do_s... |
1962 |
int notify = 0; |
1da177e4c Linux-2.6.12-rc2 |
1963 |
|
5224fa366 ptrace: Make do_s... |
1964 1965 1966 1967 1968 1969 1970 |
/* * 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... |
1971 |
__set_current_state(TASK_STOPPED); |
5224fa366 ptrace: Make do_s... |
1972 |
spin_unlock_irq(¤t->sighand->siglock); |
62bcf9d99 job control: Job ... |
1973 1974 1975 1976 1977 1978 1979 1980 1981 |
/* * 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... |
1982 1983 |
if (notify) { read_lock(&tasklist_lock); |
62bcf9d99 job control: Job ... |
1984 |
do_notify_parent_cldstop(current, false, notify); |
5224fa366 ptrace: Make do_s... |
1985 1986 1987 1988 1989 |
read_unlock(&tasklist_lock); } /* Now we don't run again until woken by SIGCONT or SIGKILL */ schedule(); |
73ddff2be job control: intr... |
1990 |
return true; |
d79fdd6d9 ptrace: Clean tra... |
1991 |
} else { |
73ddff2be job control: intr... |
1992 1993 1994 1995 1996 1997 |
/* * 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... |
1998 |
} |
73ddff2be job control: intr... |
1999 |
} |
1da177e4c Linux-2.6.12-rc2 |
2000 |
|
73ddff2be job control: intr... |
2001 2002 2003 |
/** * do_jobctl_trap - take care of ptrace jobctl traps * |
3544d72a0 ptrace: implement... |
2004 2005 2006 2007 2008 2009 2010 |
* 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... |
2011 2012 2013 2014 2015 2016 2017 |
* * 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... |
2018 |
struct signal_struct *signal = current->signal; |
73ddff2be job control: intr... |
2019 |
int signr = current->jobctl & JOBCTL_STOP_SIGMASK; |
ae6d2ed7b signals: tracehoo... |
2020 |
|
3544d72a0 ptrace: implement... |
2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 |
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... |
2032 |
} |
1da177e4c Linux-2.6.12-rc2 |
2033 |
} |
18c98b652 ptrace_signal sub... |
2034 2035 2036 |
static int ptrace_signal(int signr, siginfo_t *info, struct pt_regs *regs, void *cookie) { |
18c98b652 ptrace_signal sub... |
2037 |
ptrace_signal_deliver(regs, cookie); |
8a3524180 ptrace: fix ptrac... |
2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 |
/* * 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 ... |
2048 |
ptrace_stop(signr, CLD_TRAPPED, 0, info); |
18c98b652 ptrace_signal sub... |
2049 2050 2051 2052 2053 2054 2055 |
/* 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: ... |
2056 2057 2058 2059 2060 2061 |
/* * 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... |
2062 2063 2064 2065 |
if (signr != info->si_signo) { info->si_signo = signr; info->si_errno = 0; info->si_code = SI_USER; |
6b550f949 user namespace: m... |
2066 |
rcu_read_lock(); |
18c98b652 ptrace_signal sub... |
2067 |
info->si_pid = task_pid_vnr(current->parent); |
6b550f949 user namespace: m... |
2068 2069 2070 |
info->si_uid = map_cred_ns(__task_cred(current->parent), current_user_ns()); rcu_read_unlock(); |
18c98b652 ptrace_signal sub... |
2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 |
} /* 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 |
2081 2082 2083 |
int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie) { |
f6b76d4fb get_signal_to_del... |
2084 2085 2086 |
struct sighand_struct *sighand = current->sighand; struct signal_struct *signal = current->signal; int signr; |
1da177e4c Linux-2.6.12-rc2 |
2087 |
|
13b1c3d4b freezer vs stoppe... |
2088 2089 2090 2091 2092 2093 2094 |
relock: /* * We'll jump back here after any time we were stopped in TASK_STOPPED. * While in TASK_STOPPED, we were considered "frozen enough". * Now that we woke up, it's crucial if we're supposed to be * frozen that we freeze now before running anything substantial. */ |
fc558a749 [PATCH] swsusp: f... |
2095 |
try_to_freeze(); |
f6b76d4fb get_signal_to_del... |
2096 |
spin_lock_irq(&sighand->siglock); |
021e1ae3d signals: document... |
2097 2098 2099 2100 2101 |
/* * 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... |
2102 |
if (unlikely(signal->flags & SIGNAL_CLD_MASK)) { |
c672af35d signal: Fix SIGCO... |
2103 2104 2105 2106 2107 2108 |
int why; if (signal->flags & SIGNAL_CLD_CONTINUED) why = CLD_CONTINUED; else why = CLD_STOPPED; |
f6b76d4fb get_signal_to_del... |
2109 |
signal->flags &= ~SIGNAL_CLD_MASK; |
e44205519 signals: re-assig... |
2110 |
|
ae6d2ed7b signals: tracehoo... |
2111 |
spin_unlock_irq(&sighand->siglock); |
fa00b80b3 tracehook: job co... |
2112 |
|
ceb6bd67f job control: Noti... |
2113 2114 2115 2116 2117 2118 2119 2120 |
/* * 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... |
2121 |
read_lock(&tasklist_lock); |
ceb6bd67f job control: Noti... |
2122 |
do_notify_parent_cldstop(current, false, why); |
bb3696da8 ptrace: kill real... |
2123 2124 2125 |
if (ptrace_reparented(current->group_leader)) do_notify_parent_cldstop(current->group_leader, true, why); |
edf2ed153 ptrace: Kill trac... |
2126 |
read_unlock(&tasklist_lock); |
ceb6bd67f job control: Noti... |
2127 |
|
e44205519 signals: re-assig... |
2128 2129 |
goto relock; } |
1da177e4c Linux-2.6.12-rc2 |
2130 2131 |
for (;;) { struct k_sigaction *ka; |
1be53963b signals: check ->... |
2132 |
|
dd1d67726 signal: remove th... |
2133 2134 |
if (unlikely(current->jobctl & JOBCTL_STOP_PENDING) && do_signal_stop(0)) |
7bcf6a2ca tracehook: get_si... |
2135 |
goto relock; |
1be53963b signals: check ->... |
2136 |
|
73ddff2be job control: intr... |
2137 2138 2139 2140 2141 |
if (unlikely(current->jobctl & JOBCTL_TRAP_MASK)) { do_jobctl_trap(); spin_unlock_irq(&sighand->siglock); goto relock; } |
1da177e4c Linux-2.6.12-rc2 |
2142 |
|
dd1d67726 signal: remove th... |
2143 |
signr = dequeue_signal(current, ¤t->blocked, info); |
7bcf6a2ca tracehook: get_si... |
2144 |
|
dd1d67726 signal: remove th... |
2145 2146 |
if (!signr) break; /* will return 0 */ |
7bcf6a2ca tracehook: get_si... |
2147 |
|
8a3524180 ptrace: fix ptrac... |
2148 |
if (unlikely(current->ptrace) && signr != SIGKILL) { |
dd1d67726 signal: remove th... |
2149 2150 2151 2152 |
signr = ptrace_signal(signr, info, regs, cookie); if (!signr) continue; |
1da177e4c Linux-2.6.12-rc2 |
2153 |
} |
dd1d67726 signal: remove th... |
2154 |
ka = &sighand->action[signr-1]; |
f9d4257e0 tracepoint: Add s... |
2155 2156 |
/* Trace actually delivered signals. */ trace_signal_deliver(signr, info, ka); |
1da177e4c Linux-2.6.12-rc2 |
2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 |
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... |
2174 |
/* |
0fbc26a6c pid namespaces: a... |
2175 |
* Global init gets no signals it doesn't want. |
b3bfa0cba signals: protect ... |
2176 2177 2178 2179 2180 2181 2182 |
* 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... |
2183 |
*/ |
fae5fa44f signals: fix /sbi... |
2184 |
if (unlikely(signal->flags & SIGNAL_UNKILLABLE) && |
b3bfa0cba signals: protect ... |
2185 |
!sig_kernel_only(signr)) |
1da177e4c Linux-2.6.12-rc2 |
2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 |
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... |
2200 |
spin_unlock_irq(&sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2201 2202 |
/* signals can be posted during this window */ |
3e7cd6c41 [PATCH] pid: repl... |
2203 |
if (is_current_pgrp_orphaned()) |
1da177e4c Linux-2.6.12-rc2 |
2204 |
goto relock; |
f6b76d4fb get_signal_to_del... |
2205 |
spin_lock_irq(&sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2206 |
} |
7bcf6a2ca tracehook: get_si... |
2207 |
if (likely(do_signal_stop(info->si_signo))) { |
1da177e4c Linux-2.6.12-rc2 |
2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 |
/* 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... |
2218 |
spin_unlock_irq(&sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2219 2220 2221 2222 2223 |
/* * Anything else is fatal, maybe with a core dump. */ current->flags |= PF_SIGNALED; |
2dce81bff signals: cleanup ... |
2224 |
|
1da177e4c Linux-2.6.12-rc2 |
2225 |
if (sig_kernel_coredump(signr)) { |
2dce81bff signals: cleanup ... |
2226 |
if (print_fatal_signals) |
7bcf6a2ca tracehook: get_si... |
2227 |
print_fatal_signal(regs, info->si_signo); |
1da177e4c Linux-2.6.12-rc2 |
2228 2229 2230 2231 2232 2233 2234 2235 |
/* * 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. */ |
7bcf6a2ca tracehook: get_si... |
2236 |
do_coredump(info->si_signo, info->si_signo, regs); |
1da177e4c Linux-2.6.12-rc2 |
2237 2238 2239 2240 2241 |
} /* * Death signals, no core dump. */ |
7bcf6a2ca tracehook: get_si... |
2242 |
do_group_exit(info->si_signo); |
1da177e4c Linux-2.6.12-rc2 |
2243 2244 |
/* NOTREACHED */ } |
f6b76d4fb get_signal_to_del... |
2245 |
spin_unlock_irq(&sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2246 2247 |
return signr; } |
5e6292c0f signal: add block... |
2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 |
/** * block_sigmask - add @ka's signal mask to current->blocked * @ka: action for @signr * @signr: signal that has been successfully delivered * * This function should be called when a signal has succesfully been * delivered. It adds the mask of signals for @ka to current->blocked * so that they are blocked during the execution of the signal * handler. In addition, @signr will be blocked unless %SA_NODEFER is * set in @ka->sa.sa_flags. */ void block_sigmask(struct k_sigaction *ka, int signr) { sigset_t blocked; sigorsets(&blocked, ¤t->blocked, &ka->sa.sa_mask); if (!(ka->sa.sa_flags & SA_NODEFER)) sigaddset(&blocked, signr); set_current_blocked(&blocked); } |
0edceb7bc signal: introduce... |
2268 2269 |
/* * It could be that complete_signal() picked us to notify about the |
fec9993db signal: retarget_... |
2270 2271 |
* group-wide signal. Other threads should be notified now to take * the shared signals in @which since we will not. |
0edceb7bc signal: introduce... |
2272 |
*/ |
f646e227b signal: retarget_... |
2273 |
static void retarget_shared_pending(struct task_struct *tsk, sigset_t *which) |
0edceb7bc signal: introduce... |
2274 |
{ |
f646e227b signal: retarget_... |
2275 |
sigset_t retarget; |
0edceb7bc signal: introduce... |
2276 |
struct task_struct *t; |
f646e227b signal: retarget_... |
2277 2278 2279 |
sigandsets(&retarget, &tsk->signal->shared_pending.signal, which); if (sigisemptyset(&retarget)) return; |
0edceb7bc signal: introduce... |
2280 2281 |
t = tsk; while_each_thread(tsk, t) { |
fec9993db signal: retarget_... |
2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 |
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... |
2295 2296 |
} } |
d12619b5f fix group stop wi... |
2297 2298 2299 |
void exit_signals(struct task_struct *tsk) { int group_stop = 0; |
f646e227b signal: retarget_... |
2300 |
sigset_t unblocked; |
d12619b5f fix group stop wi... |
2301 |
|
77e4ef99d threadgroup: exte... |
2302 2303 2304 2305 2306 |
/* * @tsk is about to have PF_EXITING set - lock out users which * expect stable threadgroup. */ threadgroup_change_begin(tsk); |
5dee1707d move the related ... |
2307 2308 |
if (thread_group_empty(tsk) || signal_group_exit(tsk->signal)) { tsk->flags |= PF_EXITING; |
77e4ef99d threadgroup: exte... |
2309 |
threadgroup_change_end(tsk); |
5dee1707d move the related ... |
2310 |
return; |
d12619b5f fix group stop wi... |
2311 |
} |
5dee1707d move the related ... |
2312 |
spin_lock_irq(&tsk->sighand->siglock); |
d12619b5f fix group stop wi... |
2313 2314 2315 2316 2317 |
/* * From now this task is not visible for group-wide signals, * see wants_signal(), do_signal_stop(). */ tsk->flags |= PF_EXITING; |
77e4ef99d threadgroup: exte... |
2318 2319 |
threadgroup_change_end(tsk); |
5dee1707d move the related ... |
2320 2321 |
if (!signal_pending(tsk)) goto out; |
f646e227b signal: retarget_... |
2322 2323 2324 |
unblocked = tsk->blocked; signotset(&unblocked); retarget_shared_pending(tsk, &unblocked); |
5dee1707d move the related ... |
2325 |
|
a8f072c1d job control: rena... |
2326 |
if (unlikely(tsk->jobctl & JOBCTL_STOP_PENDING) && |
e5c1902e9 signal: Fix prema... |
2327 |
task_participate_group_stop(tsk)) |
edf2ed153 ptrace: Kill trac... |
2328 |
group_stop = CLD_STOPPED; |
5dee1707d move the related ... |
2329 |
out: |
d12619b5f fix group stop wi... |
2330 |
spin_unlock_irq(&tsk->sighand->siglock); |
62bcf9d99 job control: Job ... |
2331 2332 2333 2334 |
/* * If group stop has completed, deliver the notification. This * should always go to the real parent of the group leader. */ |
ae6d2ed7b signals: tracehoo... |
2335 |
if (unlikely(group_stop)) { |
d12619b5f fix group stop wi... |
2336 |
read_lock(&tasklist_lock); |
62bcf9d99 job control: Job ... |
2337 |
do_notify_parent_cldstop(tsk, false, group_stop); |
d12619b5f fix group stop wi... |
2338 2339 2340 |
read_unlock(&tasklist_lock); } } |
1da177e4c Linux-2.6.12-rc2 |
2341 2342 2343 2344 |
EXPORT_SYMBOL(recalc_sigpending); EXPORT_SYMBOL_GPL(dequeue_signal); EXPORT_SYMBOL(flush_signals); EXPORT_SYMBOL(force_sig); |
1da177e4c Linux-2.6.12-rc2 |
2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 |
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: ... |
2355 2356 2357 |
/** * sys_restart_syscall - restart a system call */ |
754fe8d29 [CVE-2009-0029] S... |
2358 |
SYSCALL_DEFINE0(restart_syscall) |
1da177e4c Linux-2.6.12-rc2 |
2359 2360 2361 2362 2363 2364 2365 2366 2367 |
{ 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... |
2368 2369 2370 2371 2372 |
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... |
2373 |
sigandnsets(&newblocked, newset, ¤t->blocked); |
b182801ab signal: do_sigtim... |
2374 2375 2376 2377 2378 |
retarget_shared_pending(tsk, &newblocked); } tsk->blocked = *newset; recalc_sigpending(); } |
e6fa16ab9 signal: sigprocma... |
2379 2380 2381 2382 2383 2384 |
/** * 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 |
2385 |
*/ |
e6fa16ab9 signal: sigprocma... |
2386 2387 2388 2389 2390 |
void set_current_blocked(const sigset_t *newset) { struct task_struct *tsk = current; spin_lock_irq(&tsk->sighand->siglock); |
b182801ab signal: do_sigtim... |
2391 |
__set_task_blocked(tsk, newset); |
e6fa16ab9 signal: sigprocma... |
2392 2393 |
spin_unlock_irq(&tsk->sighand->siglock); } |
1da177e4c Linux-2.6.12-rc2 |
2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 |
/* * 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... |
2405 2406 |
struct task_struct *tsk = current; sigset_t newset; |
1da177e4c Linux-2.6.12-rc2 |
2407 |
|
73ef4aeb6 signal: sigprocma... |
2408 |
/* Lockless, only current can change ->blocked, never from irq */ |
a26fd335b [PATCH] sigprocma... |
2409 |
if (oldset) |
73ef4aeb6 signal: sigprocma... |
2410 |
*oldset = tsk->blocked; |
a26fd335b [PATCH] sigprocma... |
2411 |
|
1da177e4c Linux-2.6.12-rc2 |
2412 2413 |
switch (how) { case SIG_BLOCK: |
73ef4aeb6 signal: sigprocma... |
2414 |
sigorsets(&newset, &tsk->blocked, set); |
1da177e4c Linux-2.6.12-rc2 |
2415 2416 |
break; case SIG_UNBLOCK: |
702a5073f signal: rename si... |
2417 |
sigandnsets(&newset, &tsk->blocked, set); |
1da177e4c Linux-2.6.12-rc2 |
2418 2419 |
break; case SIG_SETMASK: |
73ef4aeb6 signal: sigprocma... |
2420 |
newset = *set; |
1da177e4c Linux-2.6.12-rc2 |
2421 2422 |
break; default: |
73ef4aeb6 signal: sigprocma... |
2423 |
return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
2424 |
} |
a26fd335b [PATCH] sigprocma... |
2425 |
|
e6fa16ab9 signal: sigprocma... |
2426 |
set_current_blocked(&newset); |
73ef4aeb6 signal: sigprocma... |
2427 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
2428 |
} |
41c57892a kernel/signal.c: ... |
2429 2430 2431 |
/** * sys_rt_sigprocmask - change the list of currently blocked signals * @how: whether to add, remove, or set signals |
ada9c9331 signal.c: fix ker... |
2432 |
* @nset: stores pending signals |
41c57892a kernel/signal.c: ... |
2433 2434 2435 |
* @oset: previous value of signal mask if non-null * @sigsetsize: size of sigset_t type */ |
bb7efee2c signal: cleanup s... |
2436 |
SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, nset, |
17da2bd90 [CVE-2009-0029] S... |
2437 |
sigset_t __user *, oset, size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2438 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2439 |
sigset_t old_set, new_set; |
bb7efee2c signal: cleanup s... |
2440 |
int error; |
1da177e4c Linux-2.6.12-rc2 |
2441 2442 2443 |
/* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) |
bb7efee2c signal: cleanup s... |
2444 |
return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
2445 |
|
bb7efee2c signal: cleanup s... |
2446 2447 2448 2449 2450 |
old_set = current->blocked; if (nset) { if (copy_from_user(&new_set, nset, sizeof(sigset_t))) return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2451 |
sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); |
bb7efee2c signal: cleanup s... |
2452 |
error = sigprocmask(how, &new_set, NULL); |
1da177e4c Linux-2.6.12-rc2 |
2453 |
if (error) |
bb7efee2c signal: cleanup s... |
2454 2455 |
return error; } |
1da177e4c Linux-2.6.12-rc2 |
2456 |
|
bb7efee2c signal: cleanup s... |
2457 2458 2459 |
if (oset) { if (copy_to_user(oset, &old_set, sizeof(sigset_t))) return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2460 |
} |
bb7efee2c signal: cleanup s... |
2461 2462 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 |
} long do_sigpending(void __user *set, unsigned long sigsetsize) { long error = -EINVAL; sigset_t pending; if (sigsetsize > sizeof(sigset_t)) goto out; spin_lock_irq(¤t->sighand->siglock); sigorsets(&pending, ¤t->pending.signal, ¤t->signal->shared_pending.signal); spin_unlock_irq(¤t->sighand->siglock); /* Outside the lock because only this thread touches it. */ sigandsets(&pending, ¤t->blocked, &pending); error = -EFAULT; if (!copy_to_user(set, &pending, sigsetsize)) error = 0; out: return error; |
5aba085ed kernel/signal.c: ... |
2487 |
} |
1da177e4c Linux-2.6.12-rc2 |
2488 |
|
41c57892a kernel/signal.c: ... |
2489 2490 2491 2492 2493 2494 |
/** * sys_rt_sigpending - examine a pending signal that has been raised * while blocked * @set: stores pending signals * @sigsetsize: size of sigset_t type or larger */ |
17da2bd90 [CVE-2009-0029] S... |
2495 |
SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, set, size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 |
{ return do_sigpending(set, sigsetsize); } #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... |
2514 2515 |
* Please remember to update the signalfd_copyinfo() function * inside fs/signalfd.c too, in case siginfo_t changes. |
1da177e4c Linux-2.6.12-rc2 |
2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 |
* 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... |
2542 |
#ifdef BUS_MCEERR_AO |
5aba085ed kernel/signal.c: ... |
2543 |
/* |
a337fdac7 HWPOISON: Copy si... |
2544 |
* Other callers might not initialize the si_lsb field, |
5aba085ed kernel/signal.c: ... |
2545 |
* so check explicitly for the right codes here. |
a337fdac7 HWPOISON: Copy si... |
2546 2547 2548 2549 |
*/ 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 |
2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 |
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; 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: ... |
2573 |
/** |
943df1485 signal: introduce... |
2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 |
* 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... |
2611 2612 |
* they arrive. Unblocking is always fine, we can avoid * set_current_blocked(). |
943df1485 signal: introduce... |
2613 2614 2615 2616 2617 2618 2619 2620 2621 |
*/ 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... |
2622 |
__set_task_blocked(tsk, &tsk->real_blocked); |
943df1485 signal: introduce... |
2623 |
siginitset(&tsk->real_blocked, 0); |
b182801ab signal: do_sigtim... |
2624 |
sig = dequeue_signal(tsk, &mask, info); |
943df1485 signal: introduce... |
2625 2626 2627 2628 2629 2630 2631 2632 2633 |
} spin_unlock_irq(&tsk->sighand->siglock); if (sig) return sig; return timeout ? -EINTR : -EAGAIN; } /** |
41c57892a kernel/signal.c: ... |
2634 2635 2636 2637 2638 2639 2640 |
* 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... |
2641 2642 2643 |
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 |
2644 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2645 2646 2647 |
sigset_t these; struct timespec ts; siginfo_t info; |
943df1485 signal: introduce... |
2648 |
int ret; |
1da177e4c Linux-2.6.12-rc2 |
2649 2650 2651 2652 2653 2654 2655 |
/* 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: ... |
2656 |
|
1da177e4c Linux-2.6.12-rc2 |
2657 2658 2659 |
if (uts) { if (copy_from_user(&ts, uts, sizeof(ts))) return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2660 |
} |
943df1485 signal: introduce... |
2661 |
ret = do_sigtimedwait(&these, &info, uts ? &ts : NULL); |
1da177e4c Linux-2.6.12-rc2 |
2662 |
|
943df1485 signal: introduce... |
2663 2664 2665 |
if (ret > 0 && uinfo) { if (copy_siginfo_to_user(uinfo, &info)) ret = -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2666 2667 2668 2669 |
} return ret; } |
41c57892a kernel/signal.c: ... |
2670 2671 2672 2673 2674 |
/** * sys_kill - send a signal to a process * @pid: the PID of the process * @sig: signal to be sent */ |
17da2bd90 [CVE-2009-0029] S... |
2675 |
SYSCALL_DEFINE2(kill, pid_t, pid, int, sig) |
1da177e4c Linux-2.6.12-rc2 |
2676 2677 2678 2679 2680 2681 |
{ struct siginfo info; info.si_signo = sig; info.si_errno = 0; info.si_code = SI_USER; |
b488893a3 pid namespaces: c... |
2682 |
info.si_pid = task_tgid_vnr(current); |
76aac0e9a CRED: Wrap task c... |
2683 |
info.si_uid = current_uid(); |
1da177e4c Linux-2.6.12-rc2 |
2684 2685 2686 |
return kill_something_info(sig, &info, pid); } |
30b4ae8a4 signals: split do... |
2687 2688 |
static int do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info) |
1da177e4c Linux-2.6.12-rc2 |
2689 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2690 |
struct task_struct *p; |
30b4ae8a4 signals: split do... |
2691 |
int error = -ESRCH; |
1da177e4c Linux-2.6.12-rc2 |
2692 |
|
3547ff3ae signals: do_tkill... |
2693 |
rcu_read_lock(); |
228ebcbe6 Uninline find_tas... |
2694 |
p = find_task_by_vpid(pid); |
b488893a3 pid namespaces: c... |
2695 |
if (p && (tgid <= 0 || task_tgid_vnr(p) == tgid)) { |
30b4ae8a4 signals: split do... |
2696 |
error = check_kill_permission(sig, info, p); |
1da177e4c Linux-2.6.12-rc2 |
2697 2698 2699 2700 |
/* * The null signal is a permissions and process existence * probe. No signal is actually delivered. */ |
4a30debfb signals: introduc... |
2701 2702 2703 2704 2705 2706 2707 2708 2709 |
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 |
2710 2711 |
} } |
3547ff3ae signals: do_tkill... |
2712 |
rcu_read_unlock(); |
6dd69f106 [PATCH] Unify sys... |
2713 |
|
1da177e4c Linux-2.6.12-rc2 |
2714 2715 |
return error; } |
30b4ae8a4 signals: split do... |
2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 |
static int do_tkill(pid_t tgid, pid_t pid, int sig) { struct siginfo info; info.si_signo = sig; info.si_errno = 0; info.si_code = SI_TKILL; info.si_pid = task_tgid_vnr(current); info.si_uid = current_uid(); return do_send_specific(tgid, pid, sig, &info); } |
6dd69f106 [PATCH] Unify sys... |
2728 2729 2730 2731 2732 2733 |
/** * 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 ... |
2734 |
* This syscall also checks the @tgid and returns -ESRCH even if the PID |
6dd69f106 [PATCH] Unify sys... |
2735 2736 2737 |
* 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... |
2738 |
SYSCALL_DEFINE3(tgkill, pid_t, tgid, pid_t, pid, int, sig) |
6dd69f106 [PATCH] Unify sys... |
2739 2740 2741 2742 2743 2744 2745 |
{ /* This is only valid for single tasks */ if (pid <= 0 || tgid <= 0) return -EINVAL; return do_tkill(tgid, pid, sig); } |
41c57892a kernel/signal.c: ... |
2746 2747 2748 2749 2750 |
/** * 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 |
2751 2752 |
* Send a signal to only one task, even if it's a CLONE_THREAD task. */ |
a5f8fa9e9 [CVE-2009-0029] S... |
2753 |
SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig) |
1da177e4c Linux-2.6.12-rc2 |
2754 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2755 2756 2757 |
/* This is only valid for single tasks */ if (pid <= 0) return -EINVAL; |
6dd69f106 [PATCH] Unify sys... |
2758 |
return do_tkill(0, pid, sig); |
1da177e4c Linux-2.6.12-rc2 |
2759 |
} |
41c57892a kernel/signal.c: ... |
2760 2761 2762 2763 2764 2765 |
/** * 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... |
2766 2767 |
SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig, siginfo_t __user *, uinfo) |
1da177e4c Linux-2.6.12-rc2 |
2768 2769 2770 2771 2772 2773 2774 |
{ siginfo_t info; if (copy_from_user(&info, uinfo, sizeof(siginfo_t))) return -EFAULT; /* Not even root can pretend to send signals from the kernel. |
da48524eb Prevent rt_sigque... |
2775 2776 |
* Nor can they impersonate a kill()/tgkill(), which adds source info. */ |
243b422af Relax si_code che... |
2777 |
if (info.si_code >= 0 || info.si_code == SI_TKILL) { |
da48524eb Prevent rt_sigque... |
2778 2779 |
/* We used to allow any < 0 si_code */ WARN_ON_ONCE(info.si_code < 0); |
1da177e4c Linux-2.6.12-rc2 |
2780 |
return -EPERM; |
da48524eb Prevent rt_sigque... |
2781 |
} |
1da177e4c Linux-2.6.12-rc2 |
2782 2783 2784 2785 2786 |
info.si_signo = sig; /* POSIX.1b doesn't mention process groups. */ return kill_proc_info(sig, &info, pid); } |
62ab4505e signals: implemen... |
2787 2788 2789 2790 2791 2792 2793 |
long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info) { /* 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... |
2794 2795 |
* Nor can they impersonate a kill()/tgkill(), which adds source info. */ |
243b422af Relax si_code che... |
2796 |
if (info->si_code >= 0 || info->si_code == SI_TKILL) { |
da48524eb Prevent rt_sigque... |
2797 2798 |
/* We used to allow any < 0 si_code */ WARN_ON_ONCE(info->si_code < 0); |
62ab4505e signals: implemen... |
2799 |
return -EPERM; |
da48524eb Prevent rt_sigque... |
2800 |
} |
62ab4505e signals: implemen... |
2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 |
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); } |
88531f725 [PATCH] do_sigact... |
2816 |
int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) |
1da177e4c Linux-2.6.12-rc2 |
2817 |
{ |
93585eeaf signals: consolid... |
2818 |
struct task_struct *t = current; |
1da177e4c Linux-2.6.12-rc2 |
2819 |
struct k_sigaction *k; |
71fabd5e4 [PATCH] sigaction... |
2820 |
sigset_t mask; |
1da177e4c Linux-2.6.12-rc2 |
2821 |
|
7ed20e1ad [PATCH] convert t... |
2822 |
if (!valid_signal(sig) || sig < 1 || (act && sig_kernel_only(sig))) |
1da177e4c Linux-2.6.12-rc2 |
2823 |
return -EINVAL; |
93585eeaf signals: consolid... |
2824 |
k = &t->sighand->action[sig-1]; |
1da177e4c Linux-2.6.12-rc2 |
2825 2826 |
spin_lock_irq(¤t->sighand->siglock); |
1da177e4c Linux-2.6.12-rc2 |
2827 2828 2829 2830 |
if (oact) *oact = *k; if (act) { |
9ac95f2f9 [PATCH] do_sigact... |
2831 2832 |
sigdelsetmask(&act->sa.sa_mask, sigmask(SIGKILL) | sigmask(SIGSTOP)); |
88531f725 [PATCH] do_sigact... |
2833 |
*k = *act; |
1da177e4c Linux-2.6.12-rc2 |
2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 |
/* * 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... |
2845 |
if (sig_handler_ignored(sig_handler(t, sig), sig)) { |
71fabd5e4 [PATCH] sigaction... |
2846 2847 2848 |
sigemptyset(&mask); sigaddset(&mask, sig); rm_from_queue_full(&mask, &t->signal->shared_pending); |
1da177e4c Linux-2.6.12-rc2 |
2849 |
do { |
71fabd5e4 [PATCH] sigaction... |
2850 |
rm_from_queue_full(&mask, &t->pending); |
1da177e4c Linux-2.6.12-rc2 |
2851 2852 |
t = next_thread(t); } while (t != current); |
1da177e4c Linux-2.6.12-rc2 |
2853 |
} |
1da177e4c Linux-2.6.12-rc2 |
2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 |
} spin_unlock_irq(¤t->sighand->siglock); return 0; } int do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long sp) { stack_t oss; int error; |
0083fc2c5 do_sigaltstack: a... |
2865 2866 2867 |
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 |
2868 2869 2870 2871 2872 2873 2874 |
if (uss) { void __user *ss_sp; size_t ss_size; int ss_flags; error = -EFAULT; |
0dd8486b5 do_sigaltstack: s... |
2875 2876 2877 2878 2879 2880 |
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 |
2881 2882 2883 2884 2885 2886 2887 2888 |
goto out; error = -EPERM; if (on_sig_stack(sp)) goto out; error = -EINVAL; /* |
5aba085ed kernel/signal.c: ... |
2889 |
* Note - this code used to test ss_flags incorrectly: |
1da177e4c Linux-2.6.12-rc2 |
2890 2891 2892 |
* 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: ... |
2893 |
* mechanism. |
1da177e4c Linux-2.6.12-rc2 |
2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 |
*/ 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... |
2910 |
error = 0; |
1da177e4c Linux-2.6.12-rc2 |
2911 2912 |
if (uoss) { error = -EFAULT; |
0083fc2c5 do_sigaltstack: a... |
2913 |
if (!access_ok(VERIFY_WRITE, uoss, sizeof(*uoss))) |
1da177e4c Linux-2.6.12-rc2 |
2914 |
goto out; |
0083fc2c5 do_sigaltstack: a... |
2915 2916 2917 |
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 |
2918 |
} |
1da177e4c Linux-2.6.12-rc2 |
2919 2920 2921 2922 2923 |
out: return error; } #ifdef __ARCH_WANT_SYS_SIGPENDING |
41c57892a kernel/signal.c: ... |
2924 2925 2926 2927 |
/** * sys_sigpending - examine pending signals * @set: where mask of pending signal is returned */ |
b290ebe2c [CVE-2009-0029] S... |
2928 |
SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set) |
1da177e4c Linux-2.6.12-rc2 |
2929 2930 2931 2932 2933 2934 2935 |
{ return do_sigpending(set, sizeof(*set)); } #endif #ifdef __ARCH_WANT_SYS_SIGPROCMASK |
41c57892a kernel/signal.c: ... |
2936 2937 2938 |
/** * sys_sigprocmask - examine and change blocked signals * @how: whether to add, remove, or set signals |
b013c3992 signal: cleanup s... |
2939 |
* @nset: signals to add or remove (if non-null) |
41c57892a kernel/signal.c: ... |
2940 2941 |
* @oset: previous value of signal mask if non-null * |
5aba085ed kernel/signal.c: ... |
2942 2943 2944 |
* Some platforms have their own version with special arguments; * others support only sys_rt_sigprocmask. */ |
1da177e4c Linux-2.6.12-rc2 |
2945 |
|
b013c3992 signal: cleanup s... |
2946 |
SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset, |
b290ebe2c [CVE-2009-0029] S... |
2947 |
old_sigset_t __user *, oset) |
1da177e4c Linux-2.6.12-rc2 |
2948 |
{ |
1da177e4c Linux-2.6.12-rc2 |
2949 |
old_sigset_t old_set, new_set; |
2e4f7c776 signal: sys_sigpr... |
2950 |
sigset_t new_blocked; |
1da177e4c Linux-2.6.12-rc2 |
2951 |
|
b013c3992 signal: cleanup s... |
2952 |
old_set = current->blocked.sig[0]; |
1da177e4c Linux-2.6.12-rc2 |
2953 |
|
b013c3992 signal: cleanup s... |
2954 2955 2956 |
if (nset) { if (copy_from_user(&new_set, nset, sizeof(*nset))) return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2957 |
new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP)); |
2e4f7c776 signal: sys_sigpr... |
2958 |
new_blocked = current->blocked; |
1da177e4c Linux-2.6.12-rc2 |
2959 |
|
1da177e4c Linux-2.6.12-rc2 |
2960 |
switch (how) { |
1da177e4c Linux-2.6.12-rc2 |
2961 |
case SIG_BLOCK: |
2e4f7c776 signal: sys_sigpr... |
2962 |
sigaddsetmask(&new_blocked, new_set); |
1da177e4c Linux-2.6.12-rc2 |
2963 2964 |
break; case SIG_UNBLOCK: |
2e4f7c776 signal: sys_sigpr... |
2965 |
sigdelsetmask(&new_blocked, new_set); |
1da177e4c Linux-2.6.12-rc2 |
2966 2967 |
break; case SIG_SETMASK: |
2e4f7c776 signal: sys_sigpr... |
2968 |
new_blocked.sig[0] = new_set; |
1da177e4c Linux-2.6.12-rc2 |
2969 |
break; |
2e4f7c776 signal: sys_sigpr... |
2970 2971 |
default: return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
2972 |
} |
2e4f7c776 signal: sys_sigpr... |
2973 |
set_current_blocked(&new_blocked); |
b013c3992 signal: cleanup s... |
2974 2975 2976 |
} if (oset) { |
1da177e4c Linux-2.6.12-rc2 |
2977 |
if (copy_to_user(oset, &old_set, sizeof(*oset))) |
b013c3992 signal: cleanup s... |
2978 |
return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
2979 |
} |
b013c3992 signal: cleanup s... |
2980 2981 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
2982 2983 2984 2985 |
} #endif /* __ARCH_WANT_SYS_SIGPROCMASK */ #ifdef __ARCH_WANT_SYS_RT_SIGACTION |
41c57892a kernel/signal.c: ... |
2986 2987 2988 |
/** * sys_rt_sigaction - alter an action taken by a process * @sig: signal to be sent |
f9fa0bc1f signal.c: fix err... |
2989 2990 |
* @act: new sigaction * @oact: used to save the previous sigaction |
41c57892a kernel/signal.c: ... |
2991 2992 |
* @sigsetsize: size of sigset_t type */ |
d4e82042c [CVE-2009-0029] S... |
2993 2994 2995 2996 |
SYSCALL_DEFINE4(rt_sigaction, int, sig, const struct sigaction __user *, act, struct sigaction __user *, oact, size_t, sigsetsize) |
1da177e4c Linux-2.6.12-rc2 |
2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 |
{ 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; } #endif /* __ARCH_WANT_SYS_RT_SIGACTION */ #ifdef __ARCH_WANT_SYS_SGETMASK /* * For backwards compatibility. Functionality superseded by sigprocmask. */ |
a5f8fa9e9 [CVE-2009-0029] S... |
3026 |
SYSCALL_DEFINE0(sgetmask) |
1da177e4c Linux-2.6.12-rc2 |
3027 3028 3029 3030 |
{ /* SMP safe */ return current->blocked.sig[0]; } |
a5f8fa9e9 [CVE-2009-0029] S... |
3031 |
SYSCALL_DEFINE1(ssetmask, int, newmask) |
1da177e4c Linux-2.6.12-rc2 |
3032 |
{ |
c1095c6da signals: sys_sset... |
3033 3034 |
int old = current->blocked.sig[0]; sigset_t newset; |
1da177e4c Linux-2.6.12-rc2 |
3035 |
|
c1095c6da signals: sys_sset... |
3036 3037 |
siginitset(&newset, newmask & ~(sigmask(SIGKILL) | sigmask(SIGSTOP))); set_current_blocked(&newset); |
1da177e4c Linux-2.6.12-rc2 |
3038 3039 3040 3041 3042 3043 3044 3045 3046 |
return old; } #endif /* __ARCH_WANT_SGETMASK */ #ifdef __ARCH_WANT_SYS_SIGNAL /* * For backwards compatibility. Functionality superseded by sigaction. */ |
a5f8fa9e9 [CVE-2009-0029] S... |
3047 |
SYSCALL_DEFINE2(signal, int, sig, __sighandler_t, handler) |
1da177e4c Linux-2.6.12-rc2 |
3048 3049 3050 3051 3052 3053 |
{ 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... |
3054 |
sigemptyset(&new_sa.sa.sa_mask); |
1da177e4c Linux-2.6.12-rc2 |
3055 3056 3057 3058 3059 3060 3061 3062 |
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... |
3063 |
SYSCALL_DEFINE0(pause) |
1da177e4c Linux-2.6.12-rc2 |
3064 |
{ |
d92fcf055 signal: sys_pause... |
3065 3066 3067 3068 |
while (!signal_pending(current)) { current->state = TASK_INTERRUPTIBLE; schedule(); } |
1da177e4c Linux-2.6.12-rc2 |
3069 3070 3071 3072 |
return -ERESTARTNOHAND; } #endif |
150256d8a [PATCH] Generic s... |
3073 |
#ifdef __ARCH_WANT_SYS_RT_SIGSUSPEND |
41c57892a kernel/signal.c: ... |
3074 3075 3076 3077 3078 3079 |
/** * 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... |
3080 |
SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *, unewset, size_t, sigsetsize) |
150256d8a [PATCH] Generic s... |
3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 |
{ 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; sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP)); |
150256d8a [PATCH] Generic s... |
3091 |
current->saved_sigmask = current->blocked; |
c1095c6da signals: sys_sset... |
3092 |
set_current_blocked(&newset); |
150256d8a [PATCH] Generic s... |
3093 3094 3095 |
current->state = TASK_INTERRUPTIBLE; schedule(); |
4e4c22c71 signals: add set_... |
3096 |
set_restore_sigmask(); |
150256d8a [PATCH] Generic s... |
3097 3098 3099 |
return -ERESTARTNOHAND; } #endif /* __ARCH_WANT_SYS_RT_SIGSUSPEND */ |
f269fdd18 [PATCH] NOMMU: mo... |
3100 3101 3102 3103 |
__attribute__((weak)) const char *arch_vma_name(struct vm_area_struct *vma) { return NULL; } |
1da177e4c Linux-2.6.12-rc2 |
3104 3105 |
void __init signals_init(void) { |
0a31bd5f2 KMEM_CACHE(): sim... |
3106 |
sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC); |
1da177e4c Linux-2.6.12-rc2 |
3107 |
} |
67fc4e0cb kdb: core for kgd... |
3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 |
#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 */ |