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ipc/sem.c
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/* * linux/ipc/sem.c * Copyright (C) 1992 Krishna Balasubramanian * Copyright (C) 1995 Eric Schenk, Bruno Haible * |
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* /proc/sysvipc/sem support (c) 1999 Dragos Acostachioaie <dragos@iname.com> * * SMP-threaded, sysctl's added |
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* (c) 1999 Manfred Spraul <manfred@colorfullife.com> |
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* Enforced range limit on SEM_UNDO |
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* (c) 2001 Red Hat Inc |
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* Lockless wakeup * (c) 2003 Manfred Spraul <manfred@colorfullife.com> |
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* Further wakeup optimizations, documentation * (c) 2010 Manfred Spraul <manfred@colorfullife.com> |
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* * support for audit of ipc object properties and permission changes * Dustin Kirkland <dustin.kirkland@us.ibm.com> |
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* * namespaces support * OpenVZ, SWsoft Inc. * Pavel Emelianov <xemul@openvz.org> |
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* * Implementation notes: (May 2010) * This file implements System V semaphores. * * User space visible behavior: * - FIFO ordering for semop() operations (just FIFO, not starvation * protection) * - multiple semaphore operations that alter the same semaphore in * one semop() are handled. * - sem_ctime (time of last semctl()) is updated in the IPC_SET, SETVAL and * SETALL calls. * - two Linux specific semctl() commands: SEM_STAT, SEM_INFO. * - undo adjustments at process exit are limited to 0..SEMVMX. * - namespace are supported. * - SEMMSL, SEMMNS, SEMOPM and SEMMNI can be configured at runtine by writing * to /proc/sys/kernel/sem. * - statistics about the usage are reported in /proc/sysvipc/sem. * * Internals: * - scalability: * - all global variables are read-mostly. * - semop() calls and semctl(RMID) are synchronized by RCU. * - most operations do write operations (actually: spin_lock calls) to * the per-semaphore array structure. * Thus: Perfect SMP scaling between independent semaphore arrays. * If multiple semaphores in one array are used, then cache line * trashing on the semaphore array spinlock will limit the scaling. * - semncnt and semzcnt are calculated on demand in count_semncnt() and * count_semzcnt() * - the task that performs a successful semop() scans the list of all * sleeping tasks and completes any pending operations that can be fulfilled. * Semaphores are actively given to waiting tasks (necessary for FIFO). * (see update_queue()) * - To improve the scalability, the actual wake-up calls are performed after * dropping all locks. (see wake_up_sem_queue_prepare(), * wake_up_sem_queue_do()) * - All work is done by the waker, the woken up task does not have to do * anything - not even acquiring a lock or dropping a refcount. * - A woken up task may not even touch the semaphore array anymore, it may * have been destroyed already by a semctl(RMID). * - The synchronizations between wake-ups due to a timeout/signal and a * wake-up due to a completed semaphore operation is achieved by using an * intermediate state (IN_WAKEUP). * - UNDO values are stored in an array (one per process and per * semaphore array, lazily allocated). For backwards compatibility, multiple * modes for the UNDO variables are supported (per process, per thread) * (see copy_semundo, CLONE_SYSVSEM) * - There are two lists of the pending operations: a per-array list * and per-semaphore list (stored in the array). This allows to achieve FIFO * ordering without always scanning all pending operations. * The worst-case behavior is nevertheless O(N^2) for N wakeups. |
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*/ |
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#include <linux/slab.h> #include <linux/spinlock.h> #include <linux/init.h> #include <linux/proc_fs.h> #include <linux/time.h> |
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#include <linux/security.h> #include <linux/syscalls.h> #include <linux/audit.h> |
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#include <linux/capability.h> |
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#include <linux/seq_file.h> |
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#include <linux/rwsem.h> |
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#include <linux/nsproxy.h> |
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#include <linux/ipc_namespace.h> |
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#include <asm/uaccess.h> #include "util.h" |
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/* One semaphore structure for each semaphore in the system. */ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ struct list_head sem_pending; /* pending single-sop operations */ }; /* One queue for each sleeping process in the system. */ struct sem_queue { struct list_head simple_list; /* queue of pending operations */ struct list_head list; /* queue of pending operations */ struct task_struct *sleeper; /* this process */ struct sem_undo *undo; /* undo structure */ int pid; /* process id of requesting process */ int status; /* completion status of operation */ struct sembuf *sops; /* array of pending operations */ int nsops; /* number of operations */ int alter; /* does *sops alter the array? */ }; /* Each task has a list of undo requests. They are executed automatically * when the process exits. */ struct sem_undo { struct list_head list_proc; /* per-process list: * * all undos from one process * rcu protected */ struct rcu_head rcu; /* rcu struct for sem_undo */ struct sem_undo_list *ulp; /* back ptr to sem_undo_list */ struct list_head list_id; /* per semaphore array list: * all undos for one array */ int semid; /* semaphore set identifier */ short *semadj; /* array of adjustments */ /* one per semaphore */ }; /* sem_undo_list controls shared access to the list of sem_undo structures * that may be shared among all a CLONE_SYSVSEM task group. */ struct sem_undo_list { atomic_t refcnt; spinlock_t lock; struct list_head list_proc; }; |
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#define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) |
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#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) |
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#define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) |
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static int newary(struct ipc_namespace *, struct ipc_params *); |
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static void freeary(struct ipc_namespace *, struct kern_ipc_perm *); |
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#ifdef CONFIG_PROC_FS |
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static int sysvipc_sem_proc_show(struct seq_file *s, void *it); |
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#endif #define SEMMSL_FAST 256 /* 512 bytes on stack */ #define SEMOPM_FAST 64 /* ~ 372 bytes on stack */ /* * linked list protection: * sem_undo.id_next, * sem_array.sem_pending{,last}, * sem_array.sem_undo: sem_lock() for read/write * sem_undo.proc_next: only "current" is allowed to read/write that field. * */ |
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#define sc_semmsl sem_ctls[0] #define sc_semmns sem_ctls[1] #define sc_semopm sem_ctls[2] #define sc_semmni sem_ctls[3] |
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void sem_init_ns(struct ipc_namespace *ns) |
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{ |
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ns->sc_semmsl = SEMMSL; ns->sc_semmns = SEMMNS; ns->sc_semopm = SEMOPM; ns->sc_semmni = SEMMNI; ns->used_sems = 0; |
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ipc_init_ids(&ns->ids[IPC_SEM_IDS]); |
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} |
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#ifdef CONFIG_IPC_NS |
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void sem_exit_ns(struct ipc_namespace *ns) { |
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free_ipcs(ns, &sem_ids(ns), freeary); |
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idr_destroy(&ns->ids[IPC_SEM_IDS].ipcs_idr); |
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} |
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#endif |
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void __init sem_init (void) { |
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sem_init_ns(&init_ipc_ns); |
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ipc_init_proc_interface("sysvipc/sem", " key semid perms nsems uid gid cuid cgid otime ctime ", |
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IPC_SEM_IDS, sysvipc_sem_proc_show); |
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} |
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/* |
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* sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ |
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static inline struct sem_array *sem_lock(struct ipc_namespace *ns, int id) { |
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struct kern_ipc_perm *ipcp = ipc_lock(&sem_ids(ns), id); |
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if (IS_ERR(ipcp)) return (struct sem_array *)ipcp; |
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return container_of(ipcp, struct sem_array, sem_perm); |
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} static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, int id) { |
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struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); |
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if (IS_ERR(ipcp)) return (struct sem_array *)ipcp; |
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return container_of(ipcp, struct sem_array, sem_perm); |
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} |
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static inline void sem_lock_and_putref(struct sem_array *sma) { ipc_lock_by_ptr(&sma->sem_perm); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { ipc_rcu_getref(sma); ipc_unlock(&(sma)->sem_perm); } static inline void sem_putref(struct sem_array *sma) { ipc_lock_by_ptr(&sma->sem_perm); ipc_rcu_putref(sma); ipc_unlock(&(sma)->sem_perm); } |
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static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) { ipc_rmid(&sem_ids(ns), &s->sem_perm); } |
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/* * Lockless wakeup algorithm: * Without the check/retry algorithm a lockless wakeup is possible: * - queue.status is initialized to -EINTR before blocking. * - wakeup is performed by * * unlinking the queue entry from sma->sem_pending * * setting queue.status to IN_WAKEUP * This is the notification for the blocked thread that a * result value is imminent. * * call wake_up_process * * set queue.status to the final value. * - the previously blocked thread checks queue.status: * * if it's IN_WAKEUP, then it must wait until the value changes * * if it's not -EINTR, then the operation was completed by * update_queue. semtimedop can return queue.status without |
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* performing any operation on the sem array. |
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* * otherwise it must acquire the spinlock and check what's up. * * The two-stage algorithm is necessary to protect against the following * races: * - if queue.status is set after wake_up_process, then the woken up idle * thread could race forward and try (and fail) to acquire sma->lock * before update_queue had a chance to set queue.status * - if queue.status is written before wake_up_process and if the * blocked process is woken up by a signal between writing * queue.status and the wake_up_process, then the woken up * process could return from semtimedop and die by calling * sys_exit before wake_up_process is called. Then wake_up_process * will oops, because the task structure is already invalid. * (yes, this happened on s390 with sysv msg). * */ #define IN_WAKEUP 1 |
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/** * newary - Create a new semaphore set * @ns: namespace * @params: ptr to the structure that contains key, semflg and nsems * |
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* Called with sem_ids.rw_mutex held (as a writer) |
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*/ |
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static int newary(struct ipc_namespace *ns, struct ipc_params *params) |
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{ int id; int retval; struct sem_array *sma; int size; |
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key_t key = params->key; int nsems = params->u.nsems; int semflg = params->flg; |
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int i; |
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if (!nsems) return -EINVAL; |
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if (ns->used_sems + nsems > ns->sc_semmns) |
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return -ENOSPC; size = sizeof (*sma) + nsems * sizeof (struct sem); sma = ipc_rcu_alloc(size); if (!sma) { return -ENOMEM; } memset (sma, 0, size); sma->sem_perm.mode = (semflg & S_IRWXUGO); sma->sem_perm.key = key; sma->sem_perm.security = NULL; retval = security_sem_alloc(sma); if (retval) { ipc_rcu_putref(sma); return retval; } |
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id = ipc_addid(&sem_ids(ns), &sma->sem_perm, ns->sc_semmni); |
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if (id < 0) { |
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security_sem_free(sma); ipc_rcu_putref(sma); |
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return id; |
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} |
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ns->used_sems += nsems; |
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sma->sem_base = (struct sem *) &sma[1]; |
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for (i = 0; i < nsems; i++) INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); sma->complex_count = 0; |
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INIT_LIST_HEAD(&sma->sem_pending); |
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INIT_LIST_HEAD(&sma->list_id); |
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sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); sem_unlock(sma); |
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return sma->sem_perm.id; |
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} |
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|
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/* |
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* Called with sem_ids.rw_mutex and ipcp locked. |
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*/ |
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static inline int sem_security(struct kern_ipc_perm *ipcp, int semflg) |
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{ |
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struct sem_array *sma; sma = container_of(ipcp, struct sem_array, sem_perm); return security_sem_associate(sma, semflg); |
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} |
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/* |
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* Called with sem_ids.rw_mutex and ipcp locked. |
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*/ |
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static inline int sem_more_checks(struct kern_ipc_perm *ipcp, struct ipc_params *params) |
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{ |
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struct sem_array *sma; sma = container_of(ipcp, struct sem_array, sem_perm); if (params->u.nsems > sma->sem_nsems) |
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return -EINVAL; return 0; } |
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SYSCALL_DEFINE3(semget, key_t, key, int, nsems, int, semflg) |
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{ |
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struct ipc_namespace *ns; |
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struct ipc_ops sem_ops; struct ipc_params sem_params; |
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ns = current->nsproxy->ipc_ns; |
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|
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if (nsems < 0 || nsems > ns->sc_semmsl) |
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return -EINVAL; |
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|
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sem_ops.getnew = newary; sem_ops.associate = sem_security; sem_ops.more_checks = sem_more_checks; sem_params.key = key; sem_params.flg = semflg; sem_params.u.nsems = nsems; |
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|
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return ipcget(ns, &sem_ids(ns), &sem_ops, &sem_params); |
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} |
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/* * Determine whether a sequence of semaphore operations would succeed * all at once. Return 0 if yes, 1 if need to sleep, else return error code. */ static int try_atomic_semop (struct sem_array * sma, struct sembuf * sops, int nsops, struct sem_undo *un, int pid) { int result, sem_op; struct sembuf *sop; struct sem * curr; for (sop = sops; sop < sops + nsops; sop++) { curr = sma->sem_base + sop->sem_num; sem_op = sop->sem_op; result = curr->semval; if (!sem_op && result) goto would_block; result += sem_op; if (result < 0) goto would_block; if (result > SEMVMX) goto out_of_range; if (sop->sem_flg & SEM_UNDO) { int undo = un->semadj[sop->sem_num] - sem_op; /* * Exceeding the undo range is an error. */ if (undo < (-SEMAEM - 1) || undo > SEMAEM) goto out_of_range; } curr->semval = result; } sop--; while (sop >= sops) { sma->sem_base[sop->sem_num].sempid = pid; if (sop->sem_flg & SEM_UNDO) un->semadj[sop->sem_num] -= sop->sem_op; sop--; } |
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return 0; out_of_range: result = -ERANGE; goto undo; would_block: if (sop->sem_flg & IPC_NOWAIT) result = -EAGAIN; else result = 1; undo: sop--; while (sop >= sops) { sma->sem_base[sop->sem_num].semval -= sop->sem_op; sop--; } return result; } |
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/** wake_up_sem_queue_prepare(q, error): Prepare wake-up * @q: queue entry that must be signaled * @error: Error value for the signal * * Prepare the wake-up of the queue entry q. |
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*/ |
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static void wake_up_sem_queue_prepare(struct list_head *pt, struct sem_queue *q, int error) |
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{ |
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if (list_empty(pt)) { /* * Hold preempt off so that we don't get preempted and have the * wakee busy-wait until we're scheduled back on. */ preempt_disable(); } |
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q->status = IN_WAKEUP; |
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q->pid = error; list_add_tail(&q->simple_list, pt); } /** * wake_up_sem_queue_do(pt) - do the actual wake-up * @pt: list of tasks to be woken up * * Do the actual wake-up. * The function is called without any locks held, thus the semaphore array * could be destroyed already and the tasks can disappear as soon as the * status is set to the actual return code. */ static void wake_up_sem_queue_do(struct list_head *pt) { struct sem_queue *q, *t; int did_something; did_something = !list_empty(pt); list_for_each_entry_safe(q, t, pt, simple_list) { wake_up_process(q->sleeper); /* q can disappear immediately after writing q->status. */ smp_wmb(); q->status = q->pid; } if (did_something) preempt_enable(); |
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} |
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static void unlink_queue(struct sem_array *sma, struct sem_queue *q) { list_del(&q->list); if (q->nsops == 1) list_del(&q->simple_list); else sma->complex_count--; } |
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/** check_restart(sma, q) * @sma: semaphore array * @q: the operation that just completed * * update_queue is O(N^2) when it restarts scanning the whole queue of * waiting operations. Therefore this function checks if the restart is * really necessary. It is called after a previously waiting operation * was completed. */ static int check_restart(struct sem_array *sma, struct sem_queue *q) { struct sem *curr; struct sem_queue *h; /* if the operation didn't modify the array, then no restart */ if (q->alter == 0) return 0; /* pending complex operations are too difficult to analyse */ if (sma->complex_count) return 1; /* we were a sleeping complex operation. Too difficult */ if (q->nsops > 1) return 1; curr = sma->sem_base + q->sops[0].sem_num; /* No-one waits on this queue */ if (list_empty(&curr->sem_pending)) return 0; /* the new semaphore value */ if (curr->semval) { /* It is impossible that someone waits for the new value: * - q is a previously sleeping simple operation that * altered the array. It must be a decrement, because * simple increments never sleep. * - The value is not 0, thus wait-for-zero won't proceed. * - If there are older (higher priority) decrements * in the queue, then they have observed the original * semval value and couldn't proceed. The operation * decremented to value - thus they won't proceed either. */ BUG_ON(q->sops[0].sem_op >= 0); return 0; } /* * semval is 0. Check if there are wait-for-zero semops. * They must be the first entries in the per-semaphore simple queue */ h = list_first_entry(&curr->sem_pending, struct sem_queue, simple_list); BUG_ON(h->nsops != 1); BUG_ON(h->sops[0].sem_num != q->sops[0].sem_num); /* Yes, there is a wait-for-zero semop. Restart */ if (h->sops[0].sem_op == 0) return 1; /* Again - no-one is waiting for the new value. */ return 0; } |
636c6be82 ipc/sem.c: optimi... |
548 549 550 551 552 |
/** * update_queue(sma, semnum): Look for tasks that can be completed. * @sma: semaphore array. * @semnum: semaphore that was modified. |
0a2b9d4c7 ipc/sem.c: move w... |
553 |
* @pt: list head for the tasks that must be woken up. |
636c6be82 ipc/sem.c: optimi... |
554 555 556 557 |
* * update_queue must be called after a semaphore in a semaphore array * was modified. If multiple semaphore were modified, then @semnum * must be set to -1. |
0a2b9d4c7 ipc/sem.c: move w... |
558 559 560 |
* The tasks that must be woken up are added to @pt. The return code * is stored in q->pid. * The function return 1 if at least one semop was completed successfully. |
1da177e4c Linux-2.6.12-rc2 |
561 |
*/ |
0a2b9d4c7 ipc/sem.c: move w... |
562 |
static int update_queue(struct sem_array *sma, int semnum, struct list_head *pt) |
1da177e4c Linux-2.6.12-rc2 |
563 |
{ |
636c6be82 ipc/sem.c: optimi... |
564 565 566 567 |
struct sem_queue *q; struct list_head *walk; struct list_head *pending_list; int offset; |
0a2b9d4c7 ipc/sem.c: move w... |
568 |
int semop_completed = 0; |
636c6be82 ipc/sem.c: optimi... |
569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 |
/* if there are complex operations around, then knowing the semaphore * that was modified doesn't help us. Assume that multiple semaphores * were modified. */ if (sma->complex_count) semnum = -1; if (semnum == -1) { pending_list = &sma->sem_pending; offset = offsetof(struct sem_queue, list); } else { pending_list = &sma->sem_base[semnum].sem_pending; offset = offsetof(struct sem_queue, simple_list); } |
9cad200c7 ipc/sem.c: sem us... |
584 585 |
again: |
636c6be82 ipc/sem.c: optimi... |
586 587 |
walk = pending_list->next; while (walk != pending_list) { |
fd5db4225 ipc/sem.c: optimi... |
588 |
int error, restart; |
636c6be82 ipc/sem.c: optimi... |
589 590 591 |
q = (struct sem_queue *)((char *)walk - offset); walk = walk->next; |
1da177e4c Linux-2.6.12-rc2 |
592 |
|
d987f8b21 ipc/sem.c: optimi... |
593 594 595 596 597 598 599 600 601 602 |
/* If we are scanning the single sop, per-semaphore list of * one semaphore and that semaphore is 0, then it is not * necessary to scan the "alter" entries: simple increments * that affect only one entry succeed immediately and cannot * be in the per semaphore pending queue, and decrements * cannot be successful if the value is already 0. */ if (semnum != -1 && sma->sem_base[semnum].semval == 0 && q->alter) break; |
1da177e4c Linux-2.6.12-rc2 |
603 604 605 606 |
error = try_atomic_semop(sma, q->sops, q->nsops, q->undo, q->pid); /* Does q->sleeper still need to sleep? */ |
9cad200c7 ipc/sem.c: sem us... |
607 608 |
if (error > 0) continue; |
b97e820ff ipc/sem.c: add a ... |
609 |
unlink_queue(sma, q); |
9cad200c7 ipc/sem.c: sem us... |
610 |
|
0a2b9d4c7 ipc/sem.c: move w... |
611 |
if (error) { |
fd5db4225 ipc/sem.c: optimi... |
612 |
restart = 0; |
0a2b9d4c7 ipc/sem.c: move w... |
613 614 |
} else { semop_completed = 1; |
fd5db4225 ipc/sem.c: optimi... |
615 |
restart = check_restart(sma, q); |
0a2b9d4c7 ipc/sem.c: move w... |
616 |
} |
fd5db4225 ipc/sem.c: optimi... |
617 |
|
0a2b9d4c7 ipc/sem.c: move w... |
618 |
wake_up_sem_queue_prepare(pt, q, error); |
fd5db4225 ipc/sem.c: optimi... |
619 |
if (restart) |
9cad200c7 ipc/sem.c: sem us... |
620 |
goto again; |
1da177e4c Linux-2.6.12-rc2 |
621 |
} |
0a2b9d4c7 ipc/sem.c: move w... |
622 |
return semop_completed; |
1da177e4c Linux-2.6.12-rc2 |
623 |
} |
0a2b9d4c7 ipc/sem.c: move w... |
624 625 |
/** * do_smart_update(sma, sops, nsops, otime, pt) - optimized update_queue |
fd5db4225 ipc/sem.c: optimi... |
626 627 628 |
* @sma: semaphore array * @sops: operations that were performed * @nsops: number of operations |
0a2b9d4c7 ipc/sem.c: move w... |
629 630 |
* @otime: force setting otime * @pt: list head of the tasks that must be woken up. |
fd5db4225 ipc/sem.c: optimi... |
631 632 633 |
* * do_smart_update() does the required called to update_queue, based on the * actual changes that were performed on the semaphore array. |
0a2b9d4c7 ipc/sem.c: move w... |
634 635 636 |
* Note that the function does not do the actual wake-up: the caller is * responsible for calling wake_up_sem_queue_do(@pt). * It is safe to perform this call after dropping all locks. |
fd5db4225 ipc/sem.c: optimi... |
637 |
*/ |
0a2b9d4c7 ipc/sem.c: move w... |
638 639 |
static void do_smart_update(struct sem_array *sma, struct sembuf *sops, int nsops, int otime, struct list_head *pt) |
fd5db4225 ipc/sem.c: optimi... |
640 641 642 643 |
{ int i; if (sma->complex_count || sops == NULL) { |
0a2b9d4c7 ipc/sem.c: move w... |
644 645 646 |
if (update_queue(sma, -1, pt)) otime = 1; goto done; |
fd5db4225 ipc/sem.c: optimi... |
647 648 649 650 651 652 |
} for (i = 0; i < nsops; i++) { if (sops[i].sem_op > 0 || (sops[i].sem_op < 0 && sma->sem_base[sops[i].sem_num].semval == 0)) |
0a2b9d4c7 ipc/sem.c: move w... |
653 654 |
if (update_queue(sma, sops[i].sem_num, pt)) otime = 1; |
fd5db4225 ipc/sem.c: optimi... |
655 |
} |
0a2b9d4c7 ipc/sem.c: move w... |
656 657 658 |
done: if (otime) sma->sem_otime = get_seconds(); |
fd5db4225 ipc/sem.c: optimi... |
659 |
} |
1da177e4c Linux-2.6.12-rc2 |
660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 |
/* The following counts are associated to each semaphore: * semncnt number of tasks waiting on semval being nonzero * semzcnt number of tasks waiting on semval being zero * This model assumes that a task waits on exactly one semaphore. * Since semaphore operations are to be performed atomically, tasks actually * wait on a whole sequence of semaphores simultaneously. * The counts we return here are a rough approximation, but still * warrant that semncnt+semzcnt>0 if the task is on the pending queue. */ static int count_semncnt (struct sem_array * sma, ushort semnum) { int semncnt; struct sem_queue * q; semncnt = 0; |
a1193f8ec ipc/sem.c: conver... |
675 |
list_for_each_entry(q, &sma->sem_pending, list) { |
1da177e4c Linux-2.6.12-rc2 |
676 677 678 679 680 681 682 683 684 685 686 |
struct sembuf * sops = q->sops; int nsops = q->nsops; int i; for (i = 0; i < nsops; i++) if (sops[i].sem_num == semnum && (sops[i].sem_op < 0) && !(sops[i].sem_flg & IPC_NOWAIT)) semncnt++; } return semncnt; } |
a1193f8ec ipc/sem.c: conver... |
687 |
|
1da177e4c Linux-2.6.12-rc2 |
688 689 690 691 692 693 |
static int count_semzcnt (struct sem_array * sma, ushort semnum) { int semzcnt; struct sem_queue * q; semzcnt = 0; |
a1193f8ec ipc/sem.c: conver... |
694 |
list_for_each_entry(q, &sma->sem_pending, list) { |
1da177e4c Linux-2.6.12-rc2 |
695 696 697 698 699 700 701 702 703 704 705 |
struct sembuf * sops = q->sops; int nsops = q->nsops; int i; for (i = 0; i < nsops; i++) if (sops[i].sem_num == semnum && (sops[i].sem_op == 0) && !(sops[i].sem_flg & IPC_NOWAIT)) semzcnt++; } return semzcnt; } |
3e148c799 fix idr_find() lo... |
706 707 708 |
/* Free a semaphore set. freeary() is called with sem_ids.rw_mutex locked * as a writer and the spinlock for this semaphore set hold. sem_ids.rw_mutex * remains locked on exit. |
1da177e4c Linux-2.6.12-rc2 |
709 |
*/ |
01b8b07a5 IPC: consolidate ... |
710 |
static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) |
1da177e4c Linux-2.6.12-rc2 |
711 |
{ |
380af1b33 ipc/sem.c: rewrit... |
712 713 |
struct sem_undo *un, *tu; struct sem_queue *q, *tq; |
01b8b07a5 IPC: consolidate ... |
714 |
struct sem_array *sma = container_of(ipcp, struct sem_array, sem_perm); |
0a2b9d4c7 ipc/sem.c: move w... |
715 |
struct list_head tasks; |
1da177e4c Linux-2.6.12-rc2 |
716 |
|
380af1b33 ipc/sem.c: rewrit... |
717 |
/* Free the existing undo structures for this semaphore set. */ |
4daa28f6d ipc/sem.c: conver... |
718 |
assert_spin_locked(&sma->sem_perm.lock); |
380af1b33 ipc/sem.c: rewrit... |
719 720 721 |
list_for_each_entry_safe(un, tu, &sma->list_id, list_id) { list_del(&un->list_id); spin_lock(&un->ulp->lock); |
1da177e4c Linux-2.6.12-rc2 |
722 |
un->semid = -1; |
380af1b33 ipc/sem.c: rewrit... |
723 724 |
list_del_rcu(&un->list_proc); spin_unlock(&un->ulp->lock); |
693a8b6ee ipc,rcu: Convert ... |
725 |
kfree_rcu(un, rcu); |
380af1b33 ipc/sem.c: rewrit... |
726 |
} |
1da177e4c Linux-2.6.12-rc2 |
727 728 |
/* Wake up all pending processes and let them fail with EIDRM. */ |
0a2b9d4c7 ipc/sem.c: move w... |
729 |
INIT_LIST_HEAD(&tasks); |
380af1b33 ipc/sem.c: rewrit... |
730 |
list_for_each_entry_safe(q, tq, &sma->sem_pending, list) { |
b97e820ff ipc/sem.c: add a ... |
731 |
unlink_queue(sma, q); |
0a2b9d4c7 ipc/sem.c: move w... |
732 |
wake_up_sem_queue_prepare(&tasks, q, -EIDRM); |
1da177e4c Linux-2.6.12-rc2 |
733 |
} |
7ca7e564e ipc: store ipcs i... |
734 735 |
/* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); |
1da177e4c Linux-2.6.12-rc2 |
736 |
sem_unlock(sma); |
0a2b9d4c7 ipc/sem.c: move w... |
737 |
wake_up_sem_queue_do(&tasks); |
e38935341 [PATCH] IPC names... |
738 |
ns->used_sems -= sma->sem_nsems; |
1da177e4c Linux-2.6.12-rc2 |
739 740 741 742 743 744 745 746 747 748 749 750 |
security_sem_free(sma); ipc_rcu_putref(sma); } static unsigned long copy_semid_to_user(void __user *buf, struct semid64_ds *in, int version) { switch(version) { case IPC_64: return copy_to_user(buf, in, sizeof(*in)); case IPC_OLD: { struct semid_ds out; |
982f7c2b2 sys_semctl: fix k... |
751 |
memset(&out, 0, sizeof(out)); |
1da177e4c Linux-2.6.12-rc2 |
752 753 754 755 756 757 758 759 760 761 762 763 |
ipc64_perm_to_ipc_perm(&in->sem_perm, &out.sem_perm); out.sem_otime = in->sem_otime; out.sem_ctime = in->sem_ctime; out.sem_nsems = in->sem_nsems; return copy_to_user(buf, &out, sizeof(out)); } default: return -EINVAL; } } |
4b9fcb0ec IPC/semaphores: c... |
764 765 |
static int semctl_nolock(struct ipc_namespace *ns, int semid, int cmd, int version, union semun arg) |
1da177e4c Linux-2.6.12-rc2 |
766 |
{ |
e5cc9c7b1 ipc: remove unrea... |
767 |
int err; |
1da177e4c Linux-2.6.12-rc2 |
768 769 770 771 772 773 774 775 776 777 778 779 780 781 |
struct sem_array *sma; switch(cmd) { case IPC_INFO: case SEM_INFO: { struct seminfo seminfo; int max_id; err = security_sem_semctl(NULL, cmd); if (err) return err; memset(&seminfo,0,sizeof(seminfo)); |
e38935341 [PATCH] IPC names... |
782 783 784 785 |
seminfo.semmni = ns->sc_semmni; seminfo.semmns = ns->sc_semmns; seminfo.semmsl = ns->sc_semmsl; seminfo.semopm = ns->sc_semopm; |
1da177e4c Linux-2.6.12-rc2 |
786 787 788 789 |
seminfo.semvmx = SEMVMX; seminfo.semmnu = SEMMNU; seminfo.semmap = SEMMAP; seminfo.semume = SEMUME; |
3e148c799 fix idr_find() lo... |
790 |
down_read(&sem_ids(ns).rw_mutex); |
1da177e4c Linux-2.6.12-rc2 |
791 |
if (cmd == SEM_INFO) { |
e38935341 [PATCH] IPC names... |
792 793 |
seminfo.semusz = sem_ids(ns).in_use; seminfo.semaem = ns->used_sems; |
1da177e4c Linux-2.6.12-rc2 |
794 795 796 797 |
} else { seminfo.semusz = SEMUSZ; seminfo.semaem = SEMAEM; } |
7ca7e564e ipc: store ipcs i... |
798 |
max_id = ipc_get_maxid(&sem_ids(ns)); |
3e148c799 fix idr_find() lo... |
799 |
up_read(&sem_ids(ns).rw_mutex); |
1da177e4c Linux-2.6.12-rc2 |
800 801 802 803 |
if (copy_to_user (arg.__buf, &seminfo, sizeof(struct seminfo))) return -EFAULT; return (max_id < 0) ? 0: max_id; } |
4b9fcb0ec IPC/semaphores: c... |
804 |
case IPC_STAT: |
1da177e4c Linux-2.6.12-rc2 |
805 806 807 808 |
case SEM_STAT: { struct semid64_ds tbuf; int id; |
4b9fcb0ec IPC/semaphores: c... |
809 810 811 812 813 814 815 816 817 818 819 |
if (cmd == SEM_STAT) { sma = sem_lock(ns, semid); if (IS_ERR(sma)) return PTR_ERR(sma); id = sma->sem_perm.id; } else { sma = sem_lock_check(ns, semid); if (IS_ERR(sma)) return PTR_ERR(sma); id = 0; } |
1da177e4c Linux-2.6.12-rc2 |
820 821 |
err = -EACCES; |
b0e77598f userns: user name... |
822 |
if (ipcperms(ns, &sma->sem_perm, S_IRUGO)) |
1da177e4c Linux-2.6.12-rc2 |
823 824 825 826 827 |
goto out_unlock; err = security_sem_semctl(sma, cmd); if (err) goto out_unlock; |
023a53557 ipc: integrate ip... |
828 |
memset(&tbuf, 0, sizeof(tbuf)); |
1da177e4c Linux-2.6.12-rc2 |
829 830 831 832 833 834 835 836 837 838 839 840 |
kernel_to_ipc64_perm(&sma->sem_perm, &tbuf.sem_perm); tbuf.sem_otime = sma->sem_otime; tbuf.sem_ctime = sma->sem_ctime; tbuf.sem_nsems = sma->sem_nsems; sem_unlock(sma); if (copy_semid_to_user (arg.buf, &tbuf, version)) return -EFAULT; return id; } default: return -EINVAL; } |
1da177e4c Linux-2.6.12-rc2 |
841 842 843 844 |
out_unlock: sem_unlock(sma); return err; } |
e38935341 [PATCH] IPC names... |
845 846 |
static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int cmd, int version, union semun arg) |
1da177e4c Linux-2.6.12-rc2 |
847 848 849 850 851 852 853 |
{ struct sem_array *sma; struct sem* curr; int err; ushort fast_sem_io[SEMMSL_FAST]; ushort* sem_io = fast_sem_io; int nsems; |
0a2b9d4c7 ipc/sem.c: move w... |
854 |
struct list_head tasks; |
1da177e4c Linux-2.6.12-rc2 |
855 |
|
023a53557 ipc: integrate ip... |
856 857 858 |
sma = sem_lock_check(ns, semid); if (IS_ERR(sma)) return PTR_ERR(sma); |
1da177e4c Linux-2.6.12-rc2 |
859 |
|
0a2b9d4c7 ipc/sem.c: move w... |
860 |
INIT_LIST_HEAD(&tasks); |
1da177e4c Linux-2.6.12-rc2 |
861 |
nsems = sma->sem_nsems; |
1da177e4c Linux-2.6.12-rc2 |
862 |
err = -EACCES; |
b0e77598f userns: user name... |
863 864 |
if (ipcperms(ns, &sma->sem_perm, (cmd == SETVAL || cmd == SETALL) ? S_IWUGO : S_IRUGO)) |
1da177e4c Linux-2.6.12-rc2 |
865 866 867 868 869 870 871 872 873 874 875 876 877 878 |
goto out_unlock; err = security_sem_semctl(sma, cmd); if (err) goto out_unlock; err = -EACCES; switch (cmd) { case GETALL: { ushort __user *array = arg.array; int i; if(nsems > SEMMSL_FAST) { |
6ff379721 IPC/semaphores: c... |
879 |
sem_getref_and_unlock(sma); |
1da177e4c Linux-2.6.12-rc2 |
880 881 882 |
sem_io = ipc_alloc(sizeof(ushort)*nsems); if(sem_io == NULL) { |
6ff379721 IPC/semaphores: c... |
883 |
sem_putref(sma); |
1da177e4c Linux-2.6.12-rc2 |
884 885 |
return -ENOMEM; } |
6ff379721 IPC/semaphores: c... |
886 |
sem_lock_and_putref(sma); |
1da177e4c Linux-2.6.12-rc2 |
887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 |
if (sma->sem_perm.deleted) { sem_unlock(sma); err = -EIDRM; goto out_free; } } for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; sem_unlock(sma); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; goto out_free; } case SETALL: { int i; struct sem_undo *un; |
6ff379721 IPC/semaphores: c... |
906 |
sem_getref_and_unlock(sma); |
1da177e4c Linux-2.6.12-rc2 |
907 908 909 910 |
if(nsems > SEMMSL_FAST) { sem_io = ipc_alloc(sizeof(ushort)*nsems); if(sem_io == NULL) { |
6ff379721 IPC/semaphores: c... |
911 |
sem_putref(sma); |
1da177e4c Linux-2.6.12-rc2 |
912 913 914 915 916 |
return -ENOMEM; } } if (copy_from_user (sem_io, arg.array, nsems*sizeof(ushort))) { |
6ff379721 IPC/semaphores: c... |
917 |
sem_putref(sma); |
1da177e4c Linux-2.6.12-rc2 |
918 919 920 921 922 923 |
err = -EFAULT; goto out_free; } for (i = 0; i < nsems; i++) { if (sem_io[i] > SEMVMX) { |
6ff379721 IPC/semaphores: c... |
924 |
sem_putref(sma); |
1da177e4c Linux-2.6.12-rc2 |
925 926 927 928 |
err = -ERANGE; goto out_free; } } |
6ff379721 IPC/semaphores: c... |
929 |
sem_lock_and_putref(sma); |
1da177e4c Linux-2.6.12-rc2 |
930 931 932 933 934 935 936 937 |
if (sma->sem_perm.deleted) { sem_unlock(sma); err = -EIDRM; goto out_free; } for (i = 0; i < nsems; i++) sma->sem_base[i].semval = sem_io[i]; |
4daa28f6d ipc/sem.c: conver... |
938 939 940 |
assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) { |
1da177e4c Linux-2.6.12-rc2 |
941 942 |
for (i = 0; i < nsems; i++) un->semadj[i] = 0; |
4daa28f6d ipc/sem.c: conver... |
943 |
} |
1da177e4c Linux-2.6.12-rc2 |
944 945 |
sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ |
0a2b9d4c7 ipc/sem.c: move w... |
946 |
do_smart_update(sma, NULL, 0, 0, &tasks); |
1da177e4c Linux-2.6.12-rc2 |
947 948 949 |
err = 0; goto out_unlock; } |
1da177e4c Linux-2.6.12-rc2 |
950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 |
/* GETVAL, GETPID, GETNCTN, GETZCNT, SETVAL: fall-through */ } err = -EINVAL; if(semnum < 0 || semnum >= nsems) goto out_unlock; curr = &sma->sem_base[semnum]; switch (cmd) { case GETVAL: err = curr->semval; goto out_unlock; case GETPID: err = curr->sempid; goto out_unlock; case GETNCNT: err = count_semncnt(sma,semnum); goto out_unlock; case GETZCNT: err = count_semzcnt(sma,semnum); goto out_unlock; case SETVAL: { int val = arg.val; struct sem_undo *un; |
4daa28f6d ipc/sem.c: conver... |
975 |
|
1da177e4c Linux-2.6.12-rc2 |
976 977 978 |
err = -ERANGE; if (val > SEMVMX || val < 0) goto out_unlock; |
4daa28f6d ipc/sem.c: conver... |
979 980 |
assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) |
1da177e4c Linux-2.6.12-rc2 |
981 |
un->semadj[semnum] = 0; |
4daa28f6d ipc/sem.c: conver... |
982 |
|
1da177e4c Linux-2.6.12-rc2 |
983 |
curr->semval = val; |
b488893a3 pid namespaces: c... |
984 |
curr->sempid = task_tgid_vnr(current); |
1da177e4c Linux-2.6.12-rc2 |
985 986 |
sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ |
0a2b9d4c7 ipc/sem.c: move w... |
987 |
do_smart_update(sma, NULL, 0, 0, &tasks); |
1da177e4c Linux-2.6.12-rc2 |
988 989 990 991 992 993 |
err = 0; goto out_unlock; } } out_unlock: sem_unlock(sma); |
0a2b9d4c7 ipc/sem.c: move w... |
994 |
wake_up_sem_queue_do(&tasks); |
1da177e4c Linux-2.6.12-rc2 |
995 996 997 998 999 |
out_free: if(sem_io != fast_sem_io) ipc_free(sem_io, sizeof(ushort)*nsems); return err; } |
016d7132f IPC: get rid of t... |
1000 1001 |
static inline unsigned long copy_semid_from_user(struct semid64_ds *out, void __user *buf, int version) |
1da177e4c Linux-2.6.12-rc2 |
1002 1003 1004 |
{ switch(version) { case IPC_64: |
016d7132f IPC: get rid of t... |
1005 |
if (copy_from_user(out, buf, sizeof(*out))) |
1da177e4c Linux-2.6.12-rc2 |
1006 |
return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
1007 |
return 0; |
1da177e4c Linux-2.6.12-rc2 |
1008 1009 1010 1011 1012 1013 |
case IPC_OLD: { struct semid_ds tbuf_old; if(copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) return -EFAULT; |
016d7132f IPC: get rid of t... |
1014 1015 1016 |
out->sem_perm.uid = tbuf_old.sem_perm.uid; out->sem_perm.gid = tbuf_old.sem_perm.gid; out->sem_perm.mode = tbuf_old.sem_perm.mode; |
1da177e4c Linux-2.6.12-rc2 |
1017 1018 1019 1020 1021 1022 1023 |
return 0; } default: return -EINVAL; } } |
522bb2a2b IPC/semaphores: m... |
1024 1025 1026 1027 1028 |
/* * This function handles some semctl commands which require the rw_mutex * to be held in write mode. * NOTE: no locks must be held, the rw_mutex is taken inside this function. */ |
21a4826a7 IPC/semaphores: r... |
1029 1030 |
static int semctl_down(struct ipc_namespace *ns, int semid, int cmd, int version, union semun arg) |
1da177e4c Linux-2.6.12-rc2 |
1031 1032 1033 |
{ struct sem_array *sma; int err; |
016d7132f IPC: get rid of t... |
1034 |
struct semid64_ds semid64; |
1da177e4c Linux-2.6.12-rc2 |
1035 1036 1037 |
struct kern_ipc_perm *ipcp; if(cmd == IPC_SET) { |
016d7132f IPC: get rid of t... |
1038 |
if (copy_semid_from_user(&semid64, arg.buf, version)) |
1da177e4c Linux-2.6.12-rc2 |
1039 |
return -EFAULT; |
1da177e4c Linux-2.6.12-rc2 |
1040 |
} |
073115d6b [PATCH] Rework of... |
1041 |
|
b0e77598f userns: user name... |
1042 1043 |
ipcp = ipcctl_pre_down(ns, &sem_ids(ns), semid, cmd, &semid64.sem_perm, 0); |
a5f75e7f2 IPC: consolidate ... |
1044 1045 |
if (IS_ERR(ipcp)) return PTR_ERR(ipcp); |
073115d6b [PATCH] Rework of... |
1046 |
|
a5f75e7f2 IPC: consolidate ... |
1047 |
sma = container_of(ipcp, struct sem_array, sem_perm); |
1da177e4c Linux-2.6.12-rc2 |
1048 1049 1050 1051 1052 1053 1054 |
err = security_sem_semctl(sma, cmd); if (err) goto out_unlock; switch(cmd){ case IPC_RMID: |
01b8b07a5 IPC: consolidate ... |
1055 |
freeary(ns, ipcp); |
522bb2a2b IPC/semaphores: m... |
1056 |
goto out_up; |
1da177e4c Linux-2.6.12-rc2 |
1057 |
case IPC_SET: |
8f4a3809c IPC: introduce ip... |
1058 |
ipc_update_perm(&semid64.sem_perm, ipcp); |
1da177e4c Linux-2.6.12-rc2 |
1059 |
sma->sem_ctime = get_seconds(); |
1da177e4c Linux-2.6.12-rc2 |
1060 1061 |
break; default: |
1da177e4c Linux-2.6.12-rc2 |
1062 |
err = -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
1063 |
} |
1da177e4c Linux-2.6.12-rc2 |
1064 1065 1066 |
out_unlock: sem_unlock(sma); |
522bb2a2b IPC/semaphores: m... |
1067 1068 |
out_up: up_write(&sem_ids(ns).rw_mutex); |
1da177e4c Linux-2.6.12-rc2 |
1069 1070 |
return err; } |
6673e0c3f [CVE-2009-0029] S... |
1071 |
SYSCALL_DEFINE(semctl)(int semid, int semnum, int cmd, union semun arg) |
1da177e4c Linux-2.6.12-rc2 |
1072 1073 1074 |
{ int err = -EINVAL; int version; |
e38935341 [PATCH] IPC names... |
1075 |
struct ipc_namespace *ns; |
1da177e4c Linux-2.6.12-rc2 |
1076 1077 1078 1079 1080 |
if (semid < 0) return -EINVAL; version = ipc_parse_version(&cmd); |
e38935341 [PATCH] IPC names... |
1081 |
ns = current->nsproxy->ipc_ns; |
1da177e4c Linux-2.6.12-rc2 |
1082 1083 1084 1085 |
switch(cmd) { case IPC_INFO: case SEM_INFO: |
4b9fcb0ec IPC/semaphores: c... |
1086 |
case IPC_STAT: |
1da177e4c Linux-2.6.12-rc2 |
1087 |
case SEM_STAT: |
4b9fcb0ec IPC/semaphores: c... |
1088 |
err = semctl_nolock(ns, semid, cmd, version, arg); |
1da177e4c Linux-2.6.12-rc2 |
1089 1090 1091 1092 1093 1094 |
return err; case GETALL: case GETVAL: case GETPID: case GETNCNT: case GETZCNT: |
1da177e4c Linux-2.6.12-rc2 |
1095 1096 |
case SETVAL: case SETALL: |
e38935341 [PATCH] IPC names... |
1097 |
err = semctl_main(ns,semid,semnum,cmd,version,arg); |
1da177e4c Linux-2.6.12-rc2 |
1098 1099 1100 |
return err; case IPC_RMID: case IPC_SET: |
21a4826a7 IPC/semaphores: r... |
1101 |
err = semctl_down(ns, semid, cmd, version, arg); |
1da177e4c Linux-2.6.12-rc2 |
1102 1103 1104 1105 1106 |
return err; default: return -EINVAL; } } |
6673e0c3f [CVE-2009-0029] S... |
1107 1108 1109 1110 1111 1112 1113 |
#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS asmlinkage long SyS_semctl(int semid, int semnum, int cmd, union semun arg) { return SYSC_semctl((int) semid, (int) semnum, (int) cmd, arg); } SYSCALL_ALIAS(sys_semctl, SyS_semctl); #endif |
1da177e4c Linux-2.6.12-rc2 |
1114 |
|
1da177e4c Linux-2.6.12-rc2 |
1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 |
/* If the task doesn't already have a undo_list, then allocate one * here. We guarantee there is only one thread using this undo list, * and current is THE ONE * * If this allocation and assignment succeeds, but later * portions of this code fail, there is no need to free the sem_undo_list. * Just let it stay associated with the task, and it'll be freed later * at exit time. * * This can block, so callers must hold no locks. */ static inline int get_undo_list(struct sem_undo_list **undo_listp) { struct sem_undo_list *undo_list; |
1da177e4c Linux-2.6.12-rc2 |
1129 1130 1131 |
undo_list = current->sysvsem.undo_list; if (!undo_list) { |
2453a3062 [PATCH] ipc: repl... |
1132 |
undo_list = kzalloc(sizeof(*undo_list), GFP_KERNEL); |
1da177e4c Linux-2.6.12-rc2 |
1133 1134 |
if (undo_list == NULL) return -ENOMEM; |
00a5dfdb9 [PATCH] Fix semun... |
1135 |
spin_lock_init(&undo_list->lock); |
1da177e4c Linux-2.6.12-rc2 |
1136 |
atomic_set(&undo_list->refcnt, 1); |
4daa28f6d ipc/sem.c: conver... |
1137 |
INIT_LIST_HEAD(&undo_list->list_proc); |
1da177e4c Linux-2.6.12-rc2 |
1138 1139 1140 1141 1142 |
current->sysvsem.undo_list = undo_list; } *undo_listp = undo_list; return 0; } |
bf17bb717 ipc/sem.c: sem op... |
1143 |
static struct sem_undo *__lookup_undo(struct sem_undo_list *ulp, int semid) |
1da177e4c Linux-2.6.12-rc2 |
1144 |
{ |
bf17bb717 ipc/sem.c: sem op... |
1145 |
struct sem_undo *un; |
4daa28f6d ipc/sem.c: conver... |
1146 |
|
bf17bb717 ipc/sem.c: sem op... |
1147 1148 1149 |
list_for_each_entry_rcu(un, &ulp->list_proc, list_proc) { if (un->semid == semid) return un; |
1da177e4c Linux-2.6.12-rc2 |
1150 |
} |
4daa28f6d ipc/sem.c: conver... |
1151 |
return NULL; |
1da177e4c Linux-2.6.12-rc2 |
1152 |
} |
bf17bb717 ipc/sem.c: sem op... |
1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 |
static struct sem_undo *lookup_undo(struct sem_undo_list *ulp, int semid) { struct sem_undo *un; assert_spin_locked(&ulp->lock); un = __lookup_undo(ulp, semid); if (un) { list_del_rcu(&un->list_proc); list_add_rcu(&un->list_proc, &ulp->list_proc); } return un; } |
4daa28f6d ipc/sem.c: conver... |
1166 1167 1168 1169 1170 1171 1172 1173 |
/** * find_alloc_undo - Lookup (and if not present create) undo array * @ns: namespace * @semid: semaphore array id * * The function looks up (and if not present creates) the undo structure. * The size of the undo structure depends on the size of the semaphore * array, thus the alloc path is not that straightforward. |
380af1b33 ipc/sem.c: rewrit... |
1174 1175 |
* Lifetime-rules: sem_undo is rcu-protected, on success, the function * performs a rcu_read_lock(). |
4daa28f6d ipc/sem.c: conver... |
1176 1177 |
*/ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) |
1da177e4c Linux-2.6.12-rc2 |
1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 |
{ struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; int nsems; int error; error = get_undo_list(&ulp); if (error) return ERR_PTR(error); |
380af1b33 ipc/sem.c: rewrit... |
1188 |
rcu_read_lock(); |
c530c6ac7 IPC: cleanup some... |
1189 |
spin_lock(&ulp->lock); |
1da177e4c Linux-2.6.12-rc2 |
1190 |
un = lookup_undo(ulp, semid); |
c530c6ac7 IPC: cleanup some... |
1191 |
spin_unlock(&ulp->lock); |
1da177e4c Linux-2.6.12-rc2 |
1192 1193 |
if (likely(un!=NULL)) goto out; |
380af1b33 ipc/sem.c: rewrit... |
1194 |
rcu_read_unlock(); |
1da177e4c Linux-2.6.12-rc2 |
1195 1196 |
/* no undo structure around - allocate one. */ |
4daa28f6d ipc/sem.c: conver... |
1197 |
/* step 1: figure out the size of the semaphore array */ |
023a53557 ipc: integrate ip... |
1198 1199 |
sma = sem_lock_check(ns, semid); if (IS_ERR(sma)) |
4de85cd6d ipc/sem.c: use ER... |
1200 |
return ERR_CAST(sma); |
023a53557 ipc: integrate ip... |
1201 |
|
1da177e4c Linux-2.6.12-rc2 |
1202 |
nsems = sma->sem_nsems; |
6ff379721 IPC/semaphores: c... |
1203 |
sem_getref_and_unlock(sma); |
1da177e4c Linux-2.6.12-rc2 |
1204 |
|
4daa28f6d ipc/sem.c: conver... |
1205 |
/* step 2: allocate new undo structure */ |
4668edc33 [PATCH] kernel co... |
1206 |
new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL); |
1da177e4c Linux-2.6.12-rc2 |
1207 |
if (!new) { |
6ff379721 IPC/semaphores: c... |
1208 |
sem_putref(sma); |
1da177e4c Linux-2.6.12-rc2 |
1209 1210 |
return ERR_PTR(-ENOMEM); } |
1da177e4c Linux-2.6.12-rc2 |
1211 |
|
380af1b33 ipc/sem.c: rewrit... |
1212 |
/* step 3: Acquire the lock on semaphore array */ |
6ff379721 IPC/semaphores: c... |
1213 |
sem_lock_and_putref(sma); |
1da177e4c Linux-2.6.12-rc2 |
1214 1215 |
if (sma->sem_perm.deleted) { sem_unlock(sma); |
1da177e4c Linux-2.6.12-rc2 |
1216 1217 1218 1219 |
kfree(new); un = ERR_PTR(-EIDRM); goto out; } |
380af1b33 ipc/sem.c: rewrit... |
1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 |
spin_lock(&ulp->lock); /* * step 4: check for races: did someone else allocate the undo struct? */ un = lookup_undo(ulp, semid); if (un) { kfree(new); goto success; } |
4daa28f6d ipc/sem.c: conver... |
1230 1231 |
/* step 5: initialize & link new undo structure */ new->semadj = (short *) &new[1]; |
380af1b33 ipc/sem.c: rewrit... |
1232 |
new->ulp = ulp; |
4daa28f6d ipc/sem.c: conver... |
1233 1234 |
new->semid = semid; assert_spin_locked(&ulp->lock); |
380af1b33 ipc/sem.c: rewrit... |
1235 |
list_add_rcu(&new->list_proc, &ulp->list_proc); |
4daa28f6d ipc/sem.c: conver... |
1236 1237 |
assert_spin_locked(&sma->sem_perm.lock); list_add(&new->list_id, &sma->list_id); |
380af1b33 ipc/sem.c: rewrit... |
1238 |
un = new; |
4daa28f6d ipc/sem.c: conver... |
1239 |
|
380af1b33 ipc/sem.c: rewrit... |
1240 |
success: |
c530c6ac7 IPC: cleanup some... |
1241 |
spin_unlock(&ulp->lock); |
380af1b33 ipc/sem.c: rewrit... |
1242 1243 |
rcu_read_lock(); sem_unlock(sma); |
1da177e4c Linux-2.6.12-rc2 |
1244 1245 1246 |
out: return un; } |
c61284e99 ipc/sem.c: bugfix... |
1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 |
/** * get_queue_result - Retrieve the result code from sem_queue * @q: Pointer to queue structure * * Retrieve the return code from the pending queue. If IN_WAKEUP is found in * q->status, then we must loop until the value is replaced with the final * value: This may happen if a task is woken up by an unrelated event (e.g. * signal) and in parallel the task is woken up by another task because it got * the requested semaphores. * * The function can be called with or without holding the semaphore spinlock. */ static int get_queue_result(struct sem_queue *q) { int error; error = q->status; while (unlikely(error == IN_WAKEUP)) { cpu_relax(); error = q->status; } return error; } |
d5460c997 [CVE-2009-0029] S... |
1272 1273 |
SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unsigned, nsops, const struct timespec __user *, timeout) |
1da177e4c Linux-2.6.12-rc2 |
1274 1275 1276 1277 1278 1279 |
{ int error = -EINVAL; struct sem_array *sma; struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; |
b78755abc [PATCH] ipcsem: r... |
1280 |
int undos = 0, alter = 0, max; |
1da177e4c Linux-2.6.12-rc2 |
1281 1282 |
struct sem_queue queue; unsigned long jiffies_left = 0; |
e38935341 [PATCH] IPC names... |
1283 |
struct ipc_namespace *ns; |
0a2b9d4c7 ipc/sem.c: move w... |
1284 |
struct list_head tasks; |
e38935341 [PATCH] IPC names... |
1285 1286 |
ns = current->nsproxy->ipc_ns; |
1da177e4c Linux-2.6.12-rc2 |
1287 1288 1289 |
if (nsops < 1 || semid < 0) return -EINVAL; |
e38935341 [PATCH] IPC names... |
1290 |
if (nsops > ns->sc_semopm) |
1da177e4c Linux-2.6.12-rc2 |
1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 |
return -E2BIG; if(nsops > SEMOPM_FAST) { sops = kmalloc(sizeof(*sops)*nsops,GFP_KERNEL); if(sops==NULL) return -ENOMEM; } if (copy_from_user (sops, tsops, nsops * sizeof(*tsops))) { error=-EFAULT; goto out_free; } if (timeout) { struct timespec _timeout; if (copy_from_user(&_timeout, timeout, sizeof(*timeout))) { error = -EFAULT; goto out_free; } if (_timeout.tv_sec < 0 || _timeout.tv_nsec < 0 || _timeout.tv_nsec >= 1000000000L) { error = -EINVAL; goto out_free; } jiffies_left = timespec_to_jiffies(&_timeout); } max = 0; for (sop = sops; sop < sops + nsops; sop++) { if (sop->sem_num >= max) max = sop->sem_num; if (sop->sem_flg & SEM_UNDO) |
b78755abc [PATCH] ipcsem: r... |
1319 1320 |
undos = 1; if (sop->sem_op != 0) |
1da177e4c Linux-2.6.12-rc2 |
1321 1322 |
alter = 1; } |
1da177e4c Linux-2.6.12-rc2 |
1323 |
|
1da177e4c Linux-2.6.12-rc2 |
1324 |
if (undos) { |
4daa28f6d ipc/sem.c: conver... |
1325 |
un = find_alloc_undo(ns, semid); |
1da177e4c Linux-2.6.12-rc2 |
1326 1327 1328 1329 1330 1331 |
if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } } else un = NULL; |
0a2b9d4c7 ipc/sem.c: move w... |
1332 |
INIT_LIST_HEAD(&tasks); |
023a53557 ipc: integrate ip... |
1333 1334 |
sma = sem_lock_check(ns, semid); if (IS_ERR(sma)) { |
380af1b33 ipc/sem.c: rewrit... |
1335 1336 |
if (un) rcu_read_unlock(); |
023a53557 ipc: integrate ip... |
1337 |
error = PTR_ERR(sma); |
1da177e4c Linux-2.6.12-rc2 |
1338 |
goto out_free; |
023a53557 ipc: integrate ip... |
1339 |
} |
1da177e4c Linux-2.6.12-rc2 |
1340 |
/* |
4daa28f6d ipc/sem.c: conver... |
1341 |
* semid identifiers are not unique - find_alloc_undo may have |
1da177e4c Linux-2.6.12-rc2 |
1342 |
* allocated an undo structure, it was invalidated by an RMID |
4daa28f6d ipc/sem.c: conver... |
1343 |
* and now a new array with received the same id. Check and fail. |
25985edce Fix common misspe... |
1344 |
* This case can be detected checking un->semid. The existence of |
380af1b33 ipc/sem.c: rewrit... |
1345 |
* "un" itself is guaranteed by rcu. |
1da177e4c Linux-2.6.12-rc2 |
1346 |
*/ |
4daa28f6d ipc/sem.c: conver... |
1347 |
error = -EIDRM; |
380af1b33 ipc/sem.c: rewrit... |
1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 |
if (un) { if (un->semid == -1) { rcu_read_unlock(); goto out_unlock_free; } else { /* * rcu lock can be released, "un" cannot disappear: * - sem_lock is acquired, thus IPC_RMID is * impossible. * - exit_sem is impossible, it always operates on * current (or a dead task). */ rcu_read_unlock(); } } |
4daa28f6d ipc/sem.c: conver... |
1364 |
|
1da177e4c Linux-2.6.12-rc2 |
1365 1366 1367 1368 1369 |
error = -EFBIG; if (max >= sma->sem_nsems) goto out_unlock_free; error = -EACCES; |
b0e77598f userns: user name... |
1370 |
if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO)) |
1da177e4c Linux-2.6.12-rc2 |
1371 1372 1373 1374 1375 |
goto out_unlock_free; error = security_sem_semop(sma, sops, nsops, alter); if (error) goto out_unlock_free; |
b488893a3 pid namespaces: c... |
1376 |
error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); |
1da177e4c Linux-2.6.12-rc2 |
1377 1378 |
if (error <= 0) { if (alter && error == 0) |
0a2b9d4c7 ipc/sem.c: move w... |
1379 |
do_smart_update(sma, sops, nsops, 1, &tasks); |
636c6be82 ipc/sem.c: optimi... |
1380 |
|
1da177e4c Linux-2.6.12-rc2 |
1381 1382 1383 1384 1385 1386 1387 |
goto out_unlock_free; } /* We need to sleep on this operation, so we put the current * task into the pending queue and go to sleep. */ |
1da177e4c Linux-2.6.12-rc2 |
1388 1389 1390 |
queue.sops = sops; queue.nsops = nsops; queue.undo = un; |
b488893a3 pid namespaces: c... |
1391 |
queue.pid = task_tgid_vnr(current); |
1da177e4c Linux-2.6.12-rc2 |
1392 1393 |
queue.alter = alter; if (alter) |
a1193f8ec ipc/sem.c: conver... |
1394 |
list_add_tail(&queue.list, &sma->sem_pending); |
1da177e4c Linux-2.6.12-rc2 |
1395 |
else |
a1193f8ec ipc/sem.c: conver... |
1396 |
list_add(&queue.list, &sma->sem_pending); |
1da177e4c Linux-2.6.12-rc2 |
1397 |
|
b97e820ff ipc/sem.c: add a ... |
1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 |
if (nsops == 1) { struct sem *curr; curr = &sma->sem_base[sops->sem_num]; if (alter) list_add_tail(&queue.simple_list, &curr->sem_pending); else list_add(&queue.simple_list, &curr->sem_pending); } else { INIT_LIST_HEAD(&queue.simple_list); sma->complex_count++; } |
1da177e4c Linux-2.6.12-rc2 |
1410 1411 |
queue.status = -EINTR; queue.sleeper = current; |
0b0577f60 ipc/sem.c: handle... |
1412 1413 |
sleep_again: |
1da177e4c Linux-2.6.12-rc2 |
1414 1415 1416 1417 1418 1419 1420 |
current->state = TASK_INTERRUPTIBLE; sem_unlock(sma); if (timeout) jiffies_left = schedule_timeout(jiffies_left); else schedule(); |
c61284e99 ipc/sem.c: bugfix... |
1421 |
error = get_queue_result(&queue); |
1da177e4c Linux-2.6.12-rc2 |
1422 1423 1424 |
if (error != -EINTR) { /* fast path: update_queue already obtained all requested |
c61284e99 ipc/sem.c: bugfix... |
1425 1426 1427 1428 1429 1430 1431 |
* resources. * Perform a smp_mb(): User space could assume that semop() * is a memory barrier: Without the mb(), the cpu could * speculatively read in user space stale data that was * overwritten by the previous owner of the semaphore. */ smp_mb(); |
1da177e4c Linux-2.6.12-rc2 |
1432 1433 |
goto out_free; } |
e38935341 [PATCH] IPC names... |
1434 |
sma = sem_lock(ns, semid); |
d694ad62b ipc/sem.c: fix ra... |
1435 1436 1437 1438 1439 1440 1441 1442 1443 |
/* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. */ error = get_queue_result(&queue); /* * Array removed? If yes, leave without sem_unlock(). */ |
023a53557 ipc: integrate ip... |
1444 |
if (IS_ERR(sma)) { |
1da177e4c Linux-2.6.12-rc2 |
1445 1446 |
goto out_free; } |
c61284e99 ipc/sem.c: bugfix... |
1447 |
|
1da177e4c Linux-2.6.12-rc2 |
1448 |
/* |
d694ad62b ipc/sem.c: fix ra... |
1449 1450 |
* If queue.status != -EINTR we are woken up by another process. * Leave without unlink_queue(), but with sem_unlock(). |
1da177e4c Linux-2.6.12-rc2 |
1451 |
*/ |
c61284e99 ipc/sem.c: bugfix... |
1452 |
|
1da177e4c Linux-2.6.12-rc2 |
1453 1454 1455 1456 1457 1458 1459 1460 1461 |
if (error != -EINTR) { goto out_unlock_free; } /* * If an interrupt occurred we have to clean up the queue */ if (timeout && jiffies_left == 0) error = -EAGAIN; |
0b0577f60 ipc/sem.c: handle... |
1462 1463 1464 1465 1466 1467 |
/* * If the wakeup was spurious, just retry */ if (error == -EINTR && !signal_pending(current)) goto sleep_again; |
b97e820ff ipc/sem.c: add a ... |
1468 |
unlink_queue(sma, &queue); |
1da177e4c Linux-2.6.12-rc2 |
1469 1470 1471 |
out_unlock_free: sem_unlock(sma); |
0a2b9d4c7 ipc/sem.c: move w... |
1472 1473 |
wake_up_sem_queue_do(&tasks); |
1da177e4c Linux-2.6.12-rc2 |
1474 1475 1476 1477 1478 |
out_free: if(sops != fast_sops) kfree(sops); return error; } |
d5460c997 [CVE-2009-0029] S... |
1479 1480 |
SYSCALL_DEFINE3(semop, int, semid, struct sembuf __user *, tsops, unsigned, nsops) |
1da177e4c Linux-2.6.12-rc2 |
1481 1482 1483 1484 1485 1486 |
{ return sys_semtimedop(semid, tsops, nsops, NULL); } /* If CLONE_SYSVSEM is set, establish sharing of SEM_UNDO state between * parent and child tasks. |
1da177e4c Linux-2.6.12-rc2 |
1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 |
*/ int copy_semundo(unsigned long clone_flags, struct task_struct *tsk) { struct sem_undo_list *undo_list; int error; if (clone_flags & CLONE_SYSVSEM) { error = get_undo_list(&undo_list); if (error) return error; |
1da177e4c Linux-2.6.12-rc2 |
1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 |
atomic_inc(&undo_list->refcnt); tsk->sysvsem.undo_list = undo_list; } else tsk->sysvsem.undo_list = NULL; return 0; } /* * add semadj values to semaphores, free undo structures. * undo structures are not freed when semaphore arrays are destroyed * so some of them may be out of date. * IMPLEMENTATION NOTE: There is some confusion over whether the * set of adjustments that needs to be done should be done in an atomic * manner or not. That is, if we are attempting to decrement the semval * should we queue up and wait until we can do so legally? * The original implementation attempted to do this (queue and wait). * The current implementation does not do so. The POSIX standard * and SVID should be consulted to determine what behavior is mandated. */ void exit_sem(struct task_struct *tsk) { |
4daa28f6d ipc/sem.c: conver... |
1520 |
struct sem_undo_list *ulp; |
1da177e4c Linux-2.6.12-rc2 |
1521 |
|
4daa28f6d ipc/sem.c: conver... |
1522 1523 |
ulp = tsk->sysvsem.undo_list; if (!ulp) |
1da177e4c Linux-2.6.12-rc2 |
1524 |
return; |
9edff4ab1 ipc: sysvsem: imp... |
1525 |
tsk->sysvsem.undo_list = NULL; |
1da177e4c Linux-2.6.12-rc2 |
1526 |
|
4daa28f6d ipc/sem.c: conver... |
1527 |
if (!atomic_dec_and_test(&ulp->refcnt)) |
1da177e4c Linux-2.6.12-rc2 |
1528 |
return; |
380af1b33 ipc/sem.c: rewrit... |
1529 |
for (;;) { |
1da177e4c Linux-2.6.12-rc2 |
1530 |
struct sem_array *sma; |
380af1b33 ipc/sem.c: rewrit... |
1531 |
struct sem_undo *un; |
0a2b9d4c7 ipc/sem.c: move w... |
1532 |
struct list_head tasks; |
380af1b33 ipc/sem.c: rewrit... |
1533 |
int semid; |
4daa28f6d ipc/sem.c: conver... |
1534 |
int i; |
380af1b33 ipc/sem.c: rewrit... |
1535 |
rcu_read_lock(); |
05725f7eb rculist: use list... |
1536 1537 |
un = list_entry_rcu(ulp->list_proc.next, struct sem_undo, list_proc); |
380af1b33 ipc/sem.c: rewrit... |
1538 1539 1540 1541 1542 |
if (&un->list_proc == &ulp->list_proc) semid = -1; else semid = un->semid; rcu_read_unlock(); |
4daa28f6d ipc/sem.c: conver... |
1543 |
|
380af1b33 ipc/sem.c: rewrit... |
1544 1545 |
if (semid == -1) break; |
1da177e4c Linux-2.6.12-rc2 |
1546 |
|
380af1b33 ipc/sem.c: rewrit... |
1547 |
sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); |
1da177e4c Linux-2.6.12-rc2 |
1548 |
|
380af1b33 ipc/sem.c: rewrit... |
1549 1550 1551 |
/* exit_sem raced with IPC_RMID, nothing to do */ if (IS_ERR(sma)) continue; |
1da177e4c Linux-2.6.12-rc2 |
1552 |
|
bf17bb717 ipc/sem.c: sem op... |
1553 |
un = __lookup_undo(ulp, semid); |
380af1b33 ipc/sem.c: rewrit... |
1554 1555 1556 1557 1558 1559 1560 1561 1562 |
if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ sem_unlock(sma); continue; } /* remove un from the linked lists */ |
4daa28f6d ipc/sem.c: conver... |
1563 1564 |
assert_spin_locked(&sma->sem_perm.lock); list_del(&un->list_id); |
380af1b33 ipc/sem.c: rewrit... |
1565 1566 1567 |
spin_lock(&ulp->lock); list_del_rcu(&un->list_proc); spin_unlock(&ulp->lock); |
4daa28f6d ipc/sem.c: conver... |
1568 1569 |
/* perform adjustments registered in un */ for (i = 0; i < sma->sem_nsems; i++) { |
5f921ae96 [PATCH] sem2mutex... |
1570 |
struct sem * semaphore = &sma->sem_base[i]; |
4daa28f6d ipc/sem.c: conver... |
1571 1572 |
if (un->semadj[i]) { semaphore->semval += un->semadj[i]; |
1da177e4c Linux-2.6.12-rc2 |
1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 |
/* * Range checks of the new semaphore value, * not defined by sus: * - Some unices ignore the undo entirely * (e.g. HP UX 11i 11.22, Tru64 V5.1) * - some cap the value (e.g. FreeBSD caps * at 0, but doesn't enforce SEMVMX) * * Linux caps the semaphore value, both at 0 * and at SEMVMX. * * Manfred <manfred@colorfullife.com> */ |
5f921ae96 [PATCH] sem2mutex... |
1586 1587 1588 1589 |
if (semaphore->semval < 0) semaphore->semval = 0; if (semaphore->semval > SEMVMX) semaphore->semval = SEMVMX; |
b488893a3 pid namespaces: c... |
1590 |
semaphore->sempid = task_tgid_vnr(current); |
1da177e4c Linux-2.6.12-rc2 |
1591 1592 |
} } |
1da177e4c Linux-2.6.12-rc2 |
1593 |
/* maybe some queued-up processes were waiting for this */ |
0a2b9d4c7 ipc/sem.c: move w... |
1594 1595 |
INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); |
1da177e4c Linux-2.6.12-rc2 |
1596 |
sem_unlock(sma); |
0a2b9d4c7 ipc/sem.c: move w... |
1597 |
wake_up_sem_queue_do(&tasks); |
380af1b33 ipc/sem.c: rewrit... |
1598 |
|
693a8b6ee ipc,rcu: Convert ... |
1599 |
kfree_rcu(un, rcu); |
1da177e4c Linux-2.6.12-rc2 |
1600 |
} |
4daa28f6d ipc/sem.c: conver... |
1601 |
kfree(ulp); |
1da177e4c Linux-2.6.12-rc2 |
1602 1603 1604 |
} #ifdef CONFIG_PROC_FS |
19b4946ca [PATCH] ipc: conv... |
1605 |
static int sysvipc_sem_proc_show(struct seq_file *s, void *it) |
1da177e4c Linux-2.6.12-rc2 |
1606 |
{ |
19b4946ca [PATCH] ipc: conv... |
1607 1608 1609 |
struct sem_array *sma = it; return seq_printf(s, |
b97e820ff ipc/sem.c: add a ... |
1610 1611 |
"%10d %10d %4o %10u %5u %5u %5u %5u %10lu %10lu ", |
19b4946ca [PATCH] ipc: conv... |
1612 |
sma->sem_perm.key, |
7ca7e564e ipc: store ipcs i... |
1613 |
sma->sem_perm.id, |
19b4946ca [PATCH] ipc: conv... |
1614 1615 1616 1617 1618 1619 1620 1621 |
sma->sem_perm.mode, sma->sem_nsems, sma->sem_perm.uid, sma->sem_perm.gid, sma->sem_perm.cuid, sma->sem_perm.cgid, sma->sem_otime, sma->sem_ctime); |
1da177e4c Linux-2.6.12-rc2 |
1622 1623 |
} #endif |