cregit-Linux how code gets into the kernel

Release 4.10 kernel/signal.c

Directory: kernel
/*
 *  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.
 */

#include <linux/slab.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
#include <linux/coredump.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/ptrace.h>
#include <linux/signal.h>
#include <linux/signalfd.h>
#include <linux/ratelimit.h>
#include <linux/tracehook.h>
#include <linux/capability.h>
#include <linux/freezer.h>
#include <linux/pid_namespace.h>
#include <linux/nsproxy.h>
#include <linux/user_namespace.h>
#include <linux/uprobes.h>
#include <linux/compat.h>
#include <linux/cn_proc.h>
#include <linux/compiler.h>


#define CREATE_TRACE_POINTS
#include <trace/events/signal.h>

#include <asm/param.h>
#include <linux/uaccess.h>
#include <asm/unistd.h>
#include <asm/siginfo.h>
#include <asm/cacheflush.h>
#include "audit.h"	/* audit_signal_info() */

/*
 * SLAB caches for signal bits.
 */


static struct kmem_cache *sigqueue_cachep;


int print_fatal_signals __read_mostly;


static void __user *sig_handler(struct task_struct *t, int sig) { return t->sighand->action[sig - 1].sa.sa_handler; }

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pavel emelianovpavel emelianov1443.75%116.67%
roland mcgrathroland mcgrath721.88%116.67%
linus torvaldslinus torvalds721.88%116.67%
ingo molnaringo molnar26.25%233.33%
pre-gitpre-git26.25%116.67%
Total32100.00%6100.00%


static int sig_handler_ignored(void __user *handler, int sig) { /* Is it explicitly or implicitly ignored? */ return handler == SIG_IGN || (handler == SIG_DFL && sig_kernel_ignore(sig)); }

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pavel emelianovpavel emelianov1754.84%150.00%
roland mcgrathroland mcgrath1445.16%150.00%
Total31100.00%2100.00%


static int sig_task_ignored(struct task_struct *t, int sig, bool force) { void __user *handler; handler = sig_handler(t, sig); if (unlikely(t->signal->flags & SIGNAL_UNKILLABLE) && handler == SIG_DFL && !force) return 1; return sig_handler_ignored(handler, sig); }

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oleg nesterovoleg nesterov4267.74%240.00%
pavel emelianovpavel emelianov1219.35%120.00%
roland mcgrathroland mcgrath58.06%120.00%
sukadev bhattiprolusukadev bhattiprolu34.84%120.00%
Total62100.00%5100.00%


static int sig_ignored(struct task_struct *t, int sig, bool force) { /* * Blocked signals are never ignored, since the * signal handler may change by the time it is * unblocked. */ if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig)) return 0; if (!sig_task_ignored(t, sig, force)) return 0; /* * Tracers may want to know about even ignored signals. */ return !t->ptrace; }

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roland mcgrathroland mcgrath2335.38%225.00%
linus torvaldslinus torvalds1929.23%112.50%
oleg nesterovoleg nesterov1827.69%225.00%
tejun heotejun heo23.08%112.50%
sukadev bhattiprolusukadev bhattiprolu23.08%112.50%
pavel emelianovpavel emelianov11.54%112.50%
Total65100.00%8100.00%

/* * 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; }

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william lee irwin iiiwilliam lee irwin iii198100.00%1100.00%
Total198100.00%1100.00%

#define PENDING(p,b) has_pending_signals(&(p)->signal, (b))
static int recalc_sigpending_tsk(struct task_struct *t) { if ((t->jobctl & JOBCTL_PENDING_MASK) || PENDING(&t->pending, &t->blocked) || PENDING(&t->signal->shared_pending, &t->blocked)) { set_tsk_thread_flag(t, TIF_SIGPENDING); return 1; } /* * 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. */ return 0; }

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ingo molnaringo molnar4772.31%225.00%
roland mcgrathroland mcgrath1218.46%225.00%
tejun heotejun heo57.69%337.50%
linus torvaldslinus torvalds11.54%112.50%
Total65100.00%8100.00%

/* * 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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roland mcgrathroland mcgrath2395.83%150.00%
ingo molnaringo molnar14.17%150.00%
Total24100.00%2100.00%


void recalc_sigpending(void) { if (!recalc_sigpending_tsk(current) && !freezing(current)) clear_thread_flag(TIF_SIGPENDING); }

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ingo molnaringo molnar1246.15%250.00%
roland mcgrathroland mcgrath830.77%125.00%
rafael j. wysockirafael j. wysocki623.08%125.00%
Total26100.00%4100.00%

/* Given the mask, find the first available signal that should be serviced. */ #define SYNCHRONOUS_MASK \ (sigmask(SIGSEGV) | sigmask(SIGBUS) | sigmask(SIGILL) | \ sigmask(SIGTRAP) | sigmask(SIGFPE) | sigmask(SIGSYS))
int next_signal(struct sigpending *pending, sigset_t *mask) { unsigned long i, *s, *m, x; int sig = 0; s = pending->signal.sig; m = mask->sig; /* * 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; } switch (_NSIG_WORDS) { default: for (i = 1; i < _NSIG_WORDS; ++i) { x = *++s &~ *++m; if (!x) continue; sig = ffz(~x) + i*_NSIG_BPW + 1; break; } break; case 2: x = s[1] &~ m[1]; if (!x) break; sig = ffz(~x) + _NSIG_BPW + 1; break; case 1: /* Nothing to do */ break; } return sig; }

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pre-gitpre-git12065.93%350.00%
linus torvaldslinus torvalds5831.87%116.67%
ingo molnaringo molnar31.65%116.67%
davide libenzidavide libenzi10.55%116.67%
Total182100.00%6100.00%


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; pr_info("%s/%d: reached RLIMIT_SIGPENDING, dropped signal %d\n", current->comm, current->pid, sig); }

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naohiro ooiwanaohiro ooiwa5298.11%150.00%
wang xiaoqiangwang xiaoqiang11.89%150.00%
Total53100.00%2100.00%

/** * task_set_jobctl_pending - set jobctl pending bits * @task: target task * @mask: pending bits to set * * 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 long 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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tejun heotejun heo8898.88%150.00%
palmer dabbeltpalmer dabbelt11.12%150.00%
Total89100.00%2100.00%

/** * task_clear_jobctl_trapping - clear jobctl trapping bit * @task: target task * * 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. * * CONTEXT: * Must be called with @task->sighand->siglock held. */
void task_clear_jobctl_trapping(struct task_struct *task) { if (unlikely(task->jobctl & JOBCTL_TRAPPING)) { task->jobctl &= ~JOBCTL_TRAPPING; smp_mb(); /* advised by wake_up_bit() */ wake_up_bit(&task->jobctl, JOBCTL_TRAPPING_BIT); } }

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tejun heotejun heo4090.91%480.00%
oleg nesterovoleg nesterov49.09%120.00%
Total44100.00%5100.00%

/** * task_clear_jobctl_pending - clear jobctl pending bits * @task: target task * @mask: pending bits to clear * * 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. * * If clearing of @mask leaves no stop or trap pending, this function calls * task_clear_jobctl_trapping(). * * CONTEXT: * Must be called with @task->sighand->siglock held. */
void task_clear_jobctl_pending(struct task_struct *task, unsigned long mask) { BUG_ON(mask & ~JOBCTL_PENDING_MASK); if (mask & JOBCTL_STOP_PENDING) mask |= JOBCTL_STOP_CONSUME | JOBCTL_STOP_DEQUEUED; task->jobctl &= ~mask; if (!(task->jobctl & JOBCTL_PENDING_MASK)) task_clear_jobctl_trapping(task); }

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tejun heotejun heo5596.49%571.43%
palmer dabbeltpalmer dabbelt11.75%114.29%
oleg nesterovoleg nesterov11.75%114.29%
Total57100.00%7100.00%

/** * task_participate_group_stop - participate in a group stop * @task: task participating in a group stop * * @task has %JOBCTL_STOP_PENDING set and is participating in a group stop. * Group stop states are cleared and the group stop count is consumed if * %JOBCTL_STOP_CONSUME was set. If the consumption completes the group * stop, the appropriate %SIGNAL_* flags are set. * * CONTEXT: * Must be called with @task->sighand->siglock held. * * RETURNS: * %true if group stop completion should be notified to the parent, %false * otherwise. */
static bool task_participate_group_stop(struct task_struct *task) { struct signal_struct *sig = task->signal; bool consume = task->jobctl & JOBCTL_STOP_CONSUME; WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING)); task_clear_jobctl_pending(task, JOBCTL_STOP_PENDING); if (!consume) return false; if (!WARN_ON_ONCE(sig->group_stop_count == 0)) sig->group_stop_count--; /* * 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)) { signal_set_stop_flags(sig, SIGNAL_STOP_STOPPED); return true; } return false; }

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tejun heotejun heo10196.19%583.33%
jamie ilesjamie iles43.81%116.67%
Total105100.00%6100.00%

/* * allocate a new signal queue record * - this may be called without locks if and only if t == current, otherwise an * appropriate lock must be held to stop the target task from exiting */
static struct sigqueue * __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit) { struct sigqueue *q = NULL; struct user_struct *user; /* * Protect access to @t credentials. This can go away when all * callers hold rcu read lock. */ rcu_read_lock(); user = get_uid(__task_cred(t)->user); atomic_inc(&user->sigpending); rcu_read_unlock(); if (override_rlimit || atomic_read(&user->sigpending) <= task_rlimit(t, RLIMIT_SIGPENDING)) { q = kmem_cache_alloc(sigqueue_cachep, flags); } else { print_dropped_signal(sig); } if (unlikely(q == NULL)) { atomic_dec(&user->sigpending); free_uid(user); } else { INIT_LIST_HEAD(&q->list); q->flags = 0; q->user = user; } return q; }

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jim houstonjim houston3322.15%15.88%
roland mcgrathroland mcgrath3020.13%15.88%
pre-gitpre-git2114.09%423.53%
chris wrightchris wright1711.41%211.76%
naohiro ooiwanaohiro ooiwa138.72%15.88%
david howellsdavid howells128.05%317.65%
linus torvaldslinus torvalds117.38%211.76%
thomas gleixnerthomas gleixner74.70%15.88%
jiri slabyjiri slaby42.68%15.88%
al viroal viro10.67%15.88%
Total149100.00%17100.00%


static void __sigqueue_free(struct sigqueue *q) { 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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chris wrightchris wright1738.64%116.67%
jim houstonjim houston1738.64%116.67%
pre-gitpre-git1022.73%466.67%
Total44100.00%6100.00%


void flush_sigqueue(struct sigpending *queue) { 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); } }

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jim houstonjim houston6092.31%125.00%
pre-gitpre-git57.69%375.00%
Total65100.00%4100.00%

/* * Flush all pending signals for this kthread. */
void flush_signals(struct task_struct *t) { unsigned long flags; spin_lock_irqsave(&t->sighand->siglock, flags); clear_tsk_thread_flag(t, TIF_SIGPENDING); flush_sigqueue(&t->pending); flush_sigqueue(&t->signal->shared_pending); spin_unlock_irqrestore(&t->sighand->siglock, flags); }

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linus torvaldslinus torvalds2234.92%120.00%
oleg nesterovoleg nesterov1828.57%240.00%
pre-gitpre-git1828.57%120.00%
david howellsdavid howells57.94%120.00%
Total63100.00%5100.00%

#ifdef CONFIG_POSIX_TIMERS
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); }

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oleg nesterovoleg nesterov118100.00%1100.00%
Total118100.00%1100.00%


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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oleg nesterovoleg nesterov60100.00%1100.00%
Total60100.00%1100.00%

#endif
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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oleg nesterovoleg nesterov46100.00%1100.00%
Total46100.00%1100.00%

/* * 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; #ifdef __ARCH_HAS_SA_RESTORER ka->sa.sa_restorer = NULL; #endif sigemptyset(&ka->sa.sa_mask); ka++; } }

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pre-gitpre-git8181.00%660.00%
kees cookkees cook1212.00%110.00%
linus torvaldslinus torvalds66.00%220.00%
andrew mortonandrew morton11.00%110.00%
Total100100.00%10100.00%


int unhandled_signal(struct task_struct *tsk, int sig) { void __user *handler = tsk->sighand->action[sig-1].sa.sa_handler; if (is_global_init(tsk)) return 1; if (handler != SIG_IGN && handler != SIG_DFL) return 0; /* if ptraced, let the tracer determine */ return !tsk->ptrace; }

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masoud asgharifard sharbianimasoud asgharifard sharbiani3149.21%125.00%
roland mcgrathroland mcgrath2844.44%125.00%
tejun heotejun heo34.76%125.00%
serge hallynserge hallyn11.59%125.00%
Total63100.00%4100.00%


static void collect_signal(int sig, struct sigpending *list, siginfo_t *info) { struct sigqueue *q, *first = NULL; /* * 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) { if (first) goto still_pending; first = q; } } sigdelset(&list->signal, sig); if (first) { still_pending: list_del_init(&first->list); copy_siginfo(info, &first->info); __sigqueue_free(first); } else { /* * 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. */ info->si_signo = sig; info->si_errno = 0; info->si_code = SI_USER; info->si_pid = 0; info->si_uid = 0; } }

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pre-gitpre-git6144.53%333.33%
jim houstonjim houston5842.34%111.11%
oleg nesterovoleg nesterov1611.68%333.33%
randy dunlaprandy dunlap10.73%111.11%
linus torvaldslinus torvalds10.73%111.11%
Total137100.00%9100.00%


static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, siginfo_t *info) { int sig = next_signal(pending, mask); if (sig) collect_signal(sig, pending, info); return sig; }

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pre-gitpre-git3373.33%342.86%
ingo molnaringo molnar920.00%228.57%
linus torvaldslinus torvalds24.44%114.29%
roland mcgrathroland mcgrath12.22%114.29%
Total45100.00%7100.00%

/* * Dequeue a signal and return the element to the caller, which is * expected to free it. * * All callers have to hold the siglock. */
int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) { int signr; /* We only dequeue private signals from ourselves, we don't let * signalfd steal them */ signr = __dequeue_signal(&tsk->pending, mask, info); if (!signr) { signr = __dequeue_signal(&tsk->signal->shared_pending, mask, info); #ifdef CONFIG_POSIX_TIMERS /* * 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 * compliant with the old way of self-restarting * 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 != 0) { hrtimer_forward(tmr, tmr->base->get_time(), tsk->signal->it_real_incr); hrtimer_restart(tmr); } } #endif } recalc_sigpending(); if (!signr) return 0; if (unlikely(sig_kernel_stop(signr))) { /* * 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. */ current->jobctl |= JOBCTL_STOP_DEQUEUED; } #ifdef CONFIG_POSIX_TIMERS if ((info->si_code & __SI_MASK) == __SI_TIMER && info->si_sys_private) { /* * 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); } #endif return signr; }

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thomas gleixnerthomas gleixner6731.75%16.25%
ingo molnaringo molnar4722.27%212.50%
roland mcgrathroland mcgrath3918.48%425.00%
george anzingergeorge anzinger2411.37%16.25%
nicolas pitrenicolas pitre104.74%16.25%
linus torvaldslinus torvalds83.79%212.50%
pavel emelianovpavel emelianov73.32%16.25%
benjamin herrenschmidtbenjamin herrenschmidt52.37%16.25%
tejun heotejun heo20.95%16.25%
randy dunlaprandy dunlap10.47%16.25%
oleg nesterovoleg nesterov10.47%16.25%
Total211100.00%16100.00%

/* * 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_state(struct task_struct *t, unsigned int state) { set_tsk_thread_flag(t, TIF_SIGPENDING); /* * TASK_WAKEKILL also means wake it up in the stopped/traced/killable * case. We don't check t->state here because there is a race with it * 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. */ if (!wake_up_state(t, state | TASK_INTERRUPTIBLE)) kick_process(t); }

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ingo molnaringo molnar2153.85%233.33%
pre-gitpre-git820.51%116.67%
oleg nesterovoleg nesterov717.95%116.67%
linus torvaldslinus torvalds37.69%233.33%
Total39100.00%6100.00%

/* * Remove signals in mask from the pending set and queue. * Returns 1 if any signals were found. * * All callers must be holding the siglock. */
static int flush_sigqueue_mask(sigset_t *mask, struct sigpending *s) { struct sigqueue *q, *n; sigset_t m; sigandsets(&m, mask, &s->signal); if (sigisemptyset(&m)) return 0; sigandnsets(&s->signal, &s->signal, mask); 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; }

Contributors

PersonTokensPropCommitsCommitProp
george anzingergeorge anzinger10698.15%133.33%
oleg nesterovoleg nesterov21.85%266.67%
Total108100.00%3100.00%


static inline int is_si_special(const struct siginfo *info) { return info <= SEND_SIG_FORCED; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov18100.00%1100.00%
Total18100.00%1100.00%


static inline bool si_fromuser(const struct siginfo *info) { return info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info)); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov31100.00%1100.00%
Total31100.00%1100.00%

/* * 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 (uid_eq(cred->euid, tcred->suid) || uid_eq(cred->euid, tcred->uid) || uid_eq(cred->uid, tcred->suid) || uid_eq(cred->uid, tcred->uid)) return 1; if (ns_capable(tcred->user_ns, CAP_KILL)) return 1; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
serge hallynserge hallyn8183.51%150.00%
eric w. biedermaneric w. biederman1616.49%150.00%
Total97100.00%2100.00%

/* * Bad permissions for sending the signal * - the caller must hold the RCU read lock */
static int check_kill_permission(int sig, struct siginfo *info, struct task_struct *t) { struct pid *sid; int error; if (!valid_signal(sig)) return -EINVAL; if (!si_fromuser(info)) return 0; error = audit_signal_info(sig, t); /* Let audit system see the signal */ if (error) return error; if (!same_thread_group(current, t) && !kill_ok_by_cred(t)) { switch (sig) { case SIGCONT: sid = task_session(t); /* * 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; } } return security_task_kill(t, info, sig, 0); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov5541.67%433.33%
ingo molnaringo molnar2518.94%216.67%
pre-gitpre-git2216.67%18.33%
amy griffisamy griffis1612.12%18.33%
al viroal viro64.55%18.33%
jesper juhljesper juhl43.03%18.33%
serge hallynserge hallyn21.52%18.33%
david p. quigleydavid p. quigley21.52%18.33%
Total132100.00%12100.00%

/** * 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. * * 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. * * 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); ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING); }

Contributors

PersonTokensPropCommitsCommitProp
tejun heotejun heo5098.04%266.67%
oleg nesterovoleg nesterov11.96%133.33%
Total51100.00%3100.00%

/* * Handle magic process-wide effects of stop/continue signals. Unlike * the signal actions, these happen immediately at signal-generation * time regardless of blocking, ignoring, or handling. This does the * actual continuing for SIGCONT, but not the actual stopping for stop * 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. */
static bool prepare_signal(int sig, struct task_struct *p, bool force) { struct signal_struct *signal = p->signal; struct task_struct *t; sigset_t flush; if (signal->flags & (SIGNAL_GROUP_EXIT | SIGNAL_GROUP_COREDUMP)) { if (!(signal->flags & SIGNAL_GROUP_EXIT)) return sig == SIGKILL; /* * The process is in the middle of dying, nothing to do. */ } else if (sig_kernel_stop(sig)) { /* * This is a stop signal. Remove SIGCONT from all queues. */ siginitset(&flush, sigmask(SIGCONT)); flush_sigqueue_mask(&flush, &signal->shared_pending); for_each_thread(p, t) flush_sigqueue_mask(&flush, &t->pending); } else if (sig == SIGCONT) { unsigned int why; /* * Remove all stop signals from all queues, wake all threads. */ siginitset(&flush, SIG_KERNEL_STOP_MASK); flush_sigqueue_mask(&flush, &signal->shared_pending); for_each_thread(p, t) { flush_sigqueue_mask(&flush, &t->pending); task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING); if (likely(!(t->ptrace & PT_SEIZED))) wake_up_state(t, __TASK_STOPPED); else ptrace_trap_notify(t); } /* * 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; if (signal->flags & SIGNAL_STOP_STOPPED) why |= SIGNAL_CLD_CONTINUED; else if (signal->group_stop_count) why |= SIGNAL_CLD_STOPPED; if (why) { /* * The first thread which returns from do_signal_stop() * will take ->siglock, notice SIGNAL_CLD_MASK, and * notify its parent. See get_signal_to_deliver(). */ signal_set_stop_flags(signal, why | SIGNAL_STOP_CONTINUED); signal->group_stop_count = 0; signal->group_exit_code = 0; } } return !sig_ignored(p, sig, force); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov13349.63%1035.71%
ingo molnaringo molnar3713.81%13.57%
pre-gitpre-git2910.82%414.29%
roland mcgrathroland mcgrath259.33%414.29%
tejun heotejun heo217.84%27.14%
linus torvaldslinus torvalds155.60%414.29%
jamie ilesjamie iles41.49%13.57%
sukadev bhattiprolusukadev bhattiprolu20.75%13.57%
bhavesh p. davdabhavesh p. davda20.75%13.57%
Total268100.00%28100.00%

/* * 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); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov5677.78%266.67%
pavel emelianovpavel emelianov1622.22%133.33%
Total72100.00%3100.00%


static void complete_signal(int sig, struct task_struct *p, int group) { 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; else if (!group || thread_group_empty(p)) /* * 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. */ if (sig_fatal(p, sig) && !(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) && !sigismember(&t->real_blocked, sig) && (sig == SIGKILL || !t->ptrace)) { /* * 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 { task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); sigaddset(&t->pending.signal, SIGKILL); signal_wake_up(t, 1); } while_each_thread(p, t); return; } }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov13963.76%419.05%
pre-gitpre-git4018.35%523.81%
pavel emelianovpavel emelianov104.59%29.52%
tejun heotejun heo94.13%419.05%
roland mcgrathroland mcgrath52.29%14.76%
ingo molnaringo molnar41.83%14.76%
jim houstonjim houston41.83%14.76%
davide libenzidavide libenzi41.83%14.76%
chris wrightchris wright31.38%29.52%
Total218100.00%21100.00%

/* * 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;
} static inline int legacy_queue(struct sigpending *signals, int sig) { return (sig < SIGRTMIN) && sigismember(&signals->signal, sig); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov1856.25%120.00%
pre-gitpre-git1340.62%360.00%
george anzingergeorge anzinger13.12%120.00%
Total32100.00%5100.00%

#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; rcu_read_lock(); info->si_uid = from_kuid_munged(task_cred_xxx(t, user_ns), make_kuid(current_user_ns(), info->si_uid)); rcu_read_unlock(); }

Contributors

PersonTokensPropCommitsCommitProp
serge hallynserge hallyn5783.82%150.00%
eric w. biedermaneric w. biederman1116.18%150.00%
Total68100.00%2100.00%

#else
static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t) { return; }

Contributors

PersonTokensPropCommitsCommitProp
serge hallynserge hallyn18100.00%1100.00%
Total18100.00%1100.00%

#endif
static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, int group, int from_ancestor_ns) { struct sigpending *pending; struct sigqueue *q; int override_rlimit; int ret = 0, result; assert_spin_locked(&t->sighand->siglock); result = TRACE_SIGNAL_IGNORED; if (!prepare_signal(sig, t, from_ancestor_ns || (info == SEND_SIG_FORCED))) goto ret; pending = group ? &t->signal->shared_pending : &t->pending; /* * 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. */ result = TRACE_SIGNAL_ALREADY_PENDING; if (legacy_queue(pending, sig)) goto ret; result = TRACE_SIGNAL_DELIVERED; /* * fast-pathed signals for kernel-internal things like SIGSTOP * or SIGKILL. */ if (info == SEND_SIG_FORCED) goto out_set; /* * 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. */ if (sig < SIGRTMIN) override_rlimit = (is_si_special(info) || info->si_code >= 0); else override_rlimit = 0; q = __sigqueue_alloc(sig, t, GFP_ATOMIC | __GFP_NOTRACK_FALSE_POSITIVE, override_rlimit); if (q) { list_add_tail(&q->list, &pending->list); switch ((unsigned long) info) { case (unsigned long) SEND_SIG_NOINFO: q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_USER; q->info.si_pid = task_tgid_nr_ns(current, task_active_pid_ns(t)); q->info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); break; case (unsigned long) SEND_SIG_PRIV: 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); if (from_ancestor_ns) q->info.si_pid = 0; break; } userns_fixup_signal_uid(&q->info, t); } else if (!is_si_special(info)) { 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(). */ result = TRACE_SIGNAL_OVERFLOW_FAIL; ret = -EAGAIN; goto ret; } else { /* * This is a silent loss of information. We still * send the signal, but the *info bits are lost. */ result = TRACE_SIGNAL_LOSE_INFO; } } out_set: signalfd_notify(t, sig); sigaddset(&pending->signal, sig); complete_signal(sig, t, group); ret: trace_signal_generate(sig, info, t, group, result); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov29768.28%623.08%
ingo molnaringo molnar276.21%27.69%
vegard nossumvegard nossum255.75%13.85%
sukadev bhattiprolusukadev bhattiprolu245.52%519.23%
pre-gitpre-git173.91%27.69%
pavel emelianovpavel emelianov132.99%311.54%
serge hallynserge hallyn102.30%13.85%
masami hiramatsumasami hiramatsu92.07%13.85%
eric w. biedermaneric w. biederman61.38%13.85%
al viroal viro20.46%13.85%
david howellsdavid howells20.46%13.85%
naohiro ooiwanaohiro ooiwa20.46%13.85%
randy dunlaprandy dunlap10.23%13.85%
Total435100.00%26100.00%


static int send_signal(int sig, struct siginfo *info, struct task_struct *t, int group) { int from_ancestor_ns = 0; #ifdef CONFIG_PID_NS from_ancestor_ns = si_fromuser(info) && !task_pid_nr_ns(current, task_active_pid_ns(t)); #endif return __send_signal(sig, info, t, group, from_ancestor_ns); }

Contributors

PersonTokensPropCommitsCommitProp
sukadev bhattiprolusukadev bhattiprolu6093.75%266.67%
oleg nesterovoleg nesterov46.25%133.33%
Total64100.00%3100.00%


static void print_fatal_signal(int signr) { struct pt_regs *regs = signal_pt_regs(); pr_info("potentially unexpected fatal signal %d.\n", signr); #if defined(__i386__) && !defined(__arch_um__) pr_info("code at %08lx: ", regs->ip); { int i; for (i = 0; i < 16; i++) { unsigned char insn; if (get_user(insn, (unsigned char *)(regs->ip + i))) break; pr_cont("%02x ", insn); } } pr_cont("\n"); #endif preempt_disable(); show_regs(regs); preempt_enable(); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov6153.04%16.67%
pre-gitpre-git97.83%16.67%
ingo molnaringo molnar86.96%320.00%
al viroal viro86.96%16.67%
linus torvaldslinus torvalds76.09%16.67%
ed swierked swierk65.22%16.67%
andi kleenandi kleen54.35%16.67%
wang xiaoqiangwang xiaoqiang43.48%16.67%
greg kroah-hartmangreg kroah-hartman32.61%213.33%
valdis kletnieksvaldis kletnieks21.74%16.67%
vineet guptavineet gupta10.87%16.67%
paul e. mckenneypaul e. mckenney10.87%16.67%
Total115100.00%15100.00%


static int __init setup_print_fatal_signals(char *str) { get_option (&str, &print_fatal_signals); return 1; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds1147.83%125.00%
oleg nesterovoleg nesterov939.13%125.00%
ingo molnaringo molnar28.70%125.00%
matthew wilcoxmatthew wilcox14.35%125.00%
Total23100.00%4100.00%

__setup("print-fatal-signals=", setup_print_fatal_signals);
int __group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { return send_signal(sig, info, p, 1); }

Contributors

PersonTokensPropCommitsCommitProp
ingo molnaringo molnar1240.00%350.00%
oleg nesterovoleg nesterov1240.00%233.33%
pavel emelianovpavel emelianov620.00%116.67%
Total30100.00%6100.00%


static int specific_send_sig_info(int sig, struct siginfo *info, struct task_struct *t) { return send_signal(sig, info, t, 0); }

Contributors

PersonTokensPropCommitsCommitProp
pavel emelianovpavel emelianov2270.97%120.00%
oleg nesterovoleg nesterov722.58%240.00%
ingo molnaringo molnar26.45%240.00%
Total31100.00%5100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov67100.00%1100.00%
Total67100.00%1100.00%

/* * Force a signal that the process can't ignore: if necessary * we unblock the signal and change any SIG_IGN to SIG_DFL. * * 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. * * We don't want to have recursive SIGSEGV's etc, for example, * that is why we also clear SIGNAL_UNKILLABLE. */
int force_sig_info(int sig, struct siginfo *info, struct task_struct *t) { unsigned long int flags; int ret, blocked, ignored; struct k_sigaction *action; spin_lock_irqsave(&t->sighand->siglock, flags); 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); recalc_sigpending_and_wake(t); } } if (action->sa.sa_handler == SIG_DFL) t->signal->flags &= ~SIGNAL_UNKILLABLE; ret = specific_send_sig_info(sig, info, t); spin_unlock_irqrestore(&t->sighand->siglock, flags); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov13581.82%350.00%
ingo molnaringo molnar2917.58%233.33%
roland mcgrathroland mcgrath10.61%116.67%
Total165100.00%6100.00%

/* * Nuke all other threads in the group. */
int zap_other_threads(struct task_struct *p) { struct task_struct *t = p; int count = 0; p->signal->group_stop_count = 0; while_each_thread(p, t) { task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); count++; /* Don't bother with already dead threads */ if (t->exit_state) continue; sigaddset(&t->pending.signal, SIGKILL); signal_wake_up(t, 1); } return count; }

Contributors

PersonTokensPropCommitsCommitProp
jim houstonjim houston4152.56%111.11%
oleg nesterovoleg nesterov1924.36%111.11%
tejun heotejun heo78.97%333.33%
linus torvaldslinus torvalds67.69%111.11%
roland mcgrathroland mcgrath45.13%222.22%
ingo molnaringo molnar11.28%111.11%
Total78100.00%9100.00%


struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, unsigned long *flags) { struct sighand_struct *sighand; for (;;) { /* * Disable interrupts early to avoid deadlocks. * See rcu_read_unlock() comment header for details. */ local_irq_save(*flags); rcu_read_lock(); sighand = rcu_dereference(tsk->sighand); if (unlikely(sighand == NULL)) { rcu_read_unlock(); local_irq_restore(*flags); break; } /* * This sighand can be already freed and even reused, but * we rely on SLAB_DESTROY_BY_RCU and sighand_ctor() which * initializes ->siglock: this slab can't go away, it has * the same object type, ->siglock can't be reinitialized. * * We need to ensure that tsk->sighand is still the same * after we take the lock, we can race with de_thread() or * __exit_signal(). In the latter case the next iteration * must see ->sighand == NULL. */ spin_lock(&sighand->siglock); if (likely(sighand == tsk->sighand)) { rcu_read_unlock(); break; } spin_unlock(&sighand->siglock); rcu_read_unlock(); local_irq_restore(*flags); } return sighand; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov4034.78%333.33%
paul e. mckenneypaul e. mckenney3732.17%333.33%
jim houstonjim houston2521.74%111.11%
ingo molnaringo molnar1210.43%111.11%
namhyung kimnamhyung kim10.87%111.11%
Total115100.00%9100.00%

/* * send signal info to all the members of a group */
int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { int ret; rcu_read_lock(); ret = check_kill_permission(sig, info, p); rcu_read_unlock(); if (!ret && sig) ret = do_send_sig_info(sig, info, p, true); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov3455.74%233.33%
jim houstonjim houston1321.31%116.67%
david howellsdavid howells1016.39%116.67%
paul e. mckenneypaul e. mckenney34.92%116.67%
ingo molnaringo molnar11.64%116.67%
Total61100.00%6100.00%

/* * __kill_pgrp_info() sends a signal to a process group: this is what the tty * control characters do (^C, ^Z etc) * - the caller must hold at least a readlock on tasklist_lock */
int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp) { struct task_struct *p = NULL; int retval, success; success = 0; retval = -ESRCH; do_each_pid_task(pgrp, PIDTYPE_PGID, p) { int err = group_send_sig_info(sig, info, p); success |= !err; retval = err; } while_each_pid_task(pgrp, PIDTYPE_PGID, p); return success ? 0 : retval; }

Contributors

PersonTokensPropCommitsCommitProp
jim houstonjim houston4552.33%116.67%
linus torvaldslinus torvalds1416.28%116.67%
andrew mortonandrew morton1112.79%116.67%
kirill korotaevkirill korotaev89.30%116.67%
eric w. biedermaneric w. biederman66.98%116.67%
pawel sikorapawel sikora22.33%116.67%
Total86100.00%6100.00%


int kill_pid_info(int sig, struct siginfo *info, struct pid *pid) { int error = -ESRCH; struct task_struct *p; for (;;) { rcu_read_lock(); p = pid_task(pid, PIDTYPE_PID); if (p) error = group_send_sig_info(sig, info, p); rcu_read_unlock(); if (likely(!p || error != -ESRCH)) return error; /* * 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. */ } }

Contributors

PersonTokensPropCommitsCommitProp
jim houstonjim houston4453.01%116.67%
paul e. mckenneypaul e. mckenney1619.28%116.67%
oleg nesterovoleg nesterov89.64%116.67%
eric w. biedermaneric w. biederman78.43%116.67%
ingo molnaringo molnar67.23%116.67%
pre-gitpre-git22.41%116.67%
Total83100.00%6100.00%


int kill_proc_info(int sig, struct siginfo *info, pid_t pid) { int error; rcu_read_lock(); error = kill_pid_info(sig, info, find_vpid(pid)); rcu_read_unlock(); return error; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman4095.24%133.33%
randy dunlaprandy dunlap12.38%133.33%
pavel emelianovpavel emelianov12.38%133.33%
Total42100.00%3100.00%


static int kill_as_cred_perm(const struct cred *cred, struct task_struct *target) { const struct cred *pcred = __task_cred(target); if (!uid_eq(cred->euid, pcred->suid) && !uid_eq(cred->euid, pcred->uid) && !uid_eq(cred->uid, pcred->suid) && !uid_eq(cred->uid, pcred->uid)) return 0; return 1; }

Contributors

PersonTokensPropCommitsCommitProp
serge hallynserge hallyn6476.19%150.00%
eric w. biedermaneric w. biederman2023.81%150.00%
Total84100.00%2100.00%

/* like kill_pid_info(), but doesn't use uid/euid of "current" */
int kill_pid_info_as_cred(int sig, struct siginfo *info, struct pid *pid, const struct cred *cred, u32 secid) { int ret = -EINVAL; struct task_struct *p; unsigned long flags; if (!valid_signal(sig)) return ret; rcu_read_lock(); p = pid_task(pid, PIDTYPE_PID); if (!p) { ret = -ESRCH; goto out_unlock; } if (si_fromuser(info) && !kill_as_cred_perm(cred, p)) { ret = -EPERM; goto out_unlock; } ret = security_task_kill(p, info, sig, secid); if (ret) goto out_unlock; if (sig) { if (lock_task_sighand(p, &flags)) { ret = __send_signal(sig, info, p, 1, 0); unlock_task_sighand(p, &flags); } else ret = -ESRCH; } out_unlock: rcu_read_unlock(); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
harald welteharald welte10759.44%112.50%
david p. quigleydavid p. quigley2312.78%112.50%
thomas gleixnerthomas gleixner2312.78%112.50%
serge hallynserge hallyn137.22%112.50%
eric w. biedermaneric w. biederman63.33%112.50%
sukadev bhattiprolusukadev bhattiprolu52.78%112.50%
oleg nesterovoleg nesterov31.67%225.00%
Total180100.00%8100.00%

EXPORT_SYMBOL_GPL(kill_pid_info_as_cred); /* * 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. */
static int kill_something_info(int sig, struct siginfo *info, pid_t pid) { int ret; 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 { int retval = 0, count = 0; struct task_struct * p; for_each_process(p) { if (task_pid_vnr(p) > 1 && !same_thread_group(p, current)) { int err = group_send_sig_info(sig, info, p); ++count; if (err != -EPERM) retval = err; } } ret = count ? retval : -ESRCH; } read_unlock(&tasklist_lock); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
jim houstonjim houston7744.25%111.11%
pavel emelianovpavel emelianov5431.03%222.22%
pre-gitpre-git158.62%111.11%
eric w. biedermaneric w. biederman158.62%111.11%
ingo molnaringo molnar74.02%111.11%
sukadev bhattiprolusukadev bhattiprolu31.72%111.11%
andrew mortonandrew morton21.15%111.11%
gustavo padovangustavo padovan10.57%111.11%
Total174100.00%9100.00%

/* * These are for backward compatibility with the rest of the kernel source. */
int send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { /* * Make sure legacy kernel users don't send in bad values * (normal paths check this in check_kill_permission). */ if (!valid_signal(sig)) return -EINVAL; return do_send_sig_info(sig, info, p, false); }

Contributors

PersonTokensPropCommitsCommitProp
jim houstonjim houston2558.14%116.67%
linus torvaldslinus torvalds920.93%116.67%
jesper juhljesper juhl49.30%116.67%
oleg nesterovoleg nesterov36.98%116.67%
ingo molnaringo molnar12.33%116.67%
randy dunlaprandy dunlap12.33%116.67%
Total43100.00%6100.00%

#define __si_special(priv) \ ((priv) ? SEND_SIG_PRIV : SEND_SIG_NOINFO)
int send_sig(int sig, struct task_struct *p, int priv) { return send_sig_info(sig, __si_special(priv), p); }

Contributors

PersonTokensPropCommitsCommitProp
jim houstonjim houston1965.52%125.00%
pre-gitpre-git724.14%125.00%
ingo molnaringo molnar26.90%125.00%
oleg nesterovoleg nesterov13.45%125.00%
Total29100.00%4100.00%


void force_sig(int sig, struct task_struct *p) { force_sig_info(sig, SEND_SIG_PRIV, p); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git1150.00%133.33%
jim houstonjim houston1045.45%133.33%
oleg nesterovoleg nesterov14.55%133.33%
Total22100.00%3100.00%

/* * 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; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds76100.00%1100.00%
Total76100.00%1100.00%


int kill_pgrp(struct pid *pid, int sig, int priv) { int ret; read_lock(&tasklist_lock); ret = __kill_pgrp_info(sig, __si_special(priv), pid); read_unlock(&tasklist_lock); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman2756.25%150.00%
pavel emelianovpavel emelianov2143.75%150.00%
Total48100.00%2100.00%

EXPORT_SYMBOL(kill_pgrp);
int kill_pid(struct pid *pid, int sig, int priv) { return kill_pid_info(sig, __si_special(priv), pid); }

Contributors

PersonTokensPropCommitsCommitProp
eric w. biedermaneric w. biederman29100.00%1100.00%
Total29100.00%1100.00%

EXPORT_SYMBOL(kill_pid); /* * 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 * expirations or I/O completions". In the case of POSIX Timers * 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. */
struct sigqueue *sigqueue_alloc(void) { struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0); if (q) q->flags |= SIGQUEUE_PREALLOC; return q; }

Contributors

PersonTokensPropCommitsCommitProp
jim houstonjim houston1435.90%120.00%
pre-gitpre-git1025.64%120.00%
naohiro ooiwanaohiro ooiwa820.51%120.00%
chris wrightchris wright512.82%120.00%
roland mcgrathroland mcgrath25.13%120.00%
Total39100.00%5100.00%


void sigqueue_free(struct sigqueue *q) { unsigned long flags; spinlock_t *lock = &current->sighand->siglock; BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); /* * We must hold ->siglock while testing q->list * to serialize with collect_signal() or with * __exit_signal()->flush_sigqueue(). */ spin_lock_irqsave(lock, flags); q->flags &= ~SIGQUEUE_PREALLOC; /* * If it is queued it will be freed when dequeued, * like the "regular" sigqueue. */ if (!list_empty(&q->list)) q = NULL; spin_unlock_irqrestore(lock, flags); if (q) __sigqueue_free(q); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov3339.29%360.00%
jim houstonjim houston3035.71%120.00%
pre-gitpre-git2125.00%120.00%
Total84100.00%5100.00%


int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group) { int sig = q->info.si_signo; struct sigpending *pending; unsigned long flags; int ret, result; BUG_ON(!(q->flags & SIGQUEUE_PREALLOC)); ret = -1; if (!likely(lock_task_sighand(t, &flags))) goto ret; ret = 1; /* the signal is ignored */ result = TRACE_SIGNAL_IGNORED; if (!prepare_signal(sig, t, false)) goto out; ret = 0; if (unlikely(!list_empty(&q->list))) { /* * If an SI_TIMER entry is already queue just increment * the overrun count. */ BUG_ON(q->info.si_code != SI_TIMER); q->info.si_overrun++; result = TRACE_SIGNAL_ALREADY_PENDING; goto out; } q->info.si_overrun = 0; signalfd_notify(t, sig); pending = group ? &t->signal->shared_pending : &t->pending; list_add_tail(&q->list, &pending->list); sigaddset(&pending->signal, sig); complete_signal(sig, t, group); result = TRACE_SIGNAL_DELIVERED; out: trace_signal_generate(sig, &q->info, t, group, result); unlock_task_sighand(t, &flags); ret: return ret; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov14158.02%853.33%
jim houstonjim houston5321.81%16.67%
pavel emelianovpavel emelianov3313.58%213.33%
davide libenzidavide libenzi62.47%16.67%
ingo molnaringo molnar52.06%16.67%
pre-gitpre-git41.65%16.67%
sukadev bhattiprolusukadev bhattiprolu10.41%16.67%
Total243100.00%15100.00%

/* * Let a parent know about the death of a child. * For a stopped/continued status change, use do_notify_parent_cldstop instead. * * Returns true if our parent ignored us and so we've switched to * self-reaping. */
bool do_notify_parent(struct task_struct *tsk, int sig) { struct siginfo info; unsigned long flags; struct sighand_struct *psig; bool autoreap = false; cputime_t utime, stime; BUG_ON(sig == -1); /* do_notify_parent_cldstop should have been called instead. */ BUG_ON(task_is_stopped_or_traced(tsk)); BUG_ON(!tsk->ptrace && (tsk->group_leader != tsk || !thread_group_empty(tsk))); if (sig != SIGCHLD) { /* * This is only possible if parent == real_parent. * Check if it has changed security domain. */ if (tsk->parent_exec_id != tsk->parent->self_exec_id) sig = SIGCHLD; } info.si_signo = sig; info.si_errno = 0; /* * We are under tasklist_lock here so our parent is tied to * us and cannot change. * * task_active_pid_ns will always return the same pid namespace * until a task passes through release_task. * * 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, task_active_pid_ns(tsk->parent)); info.si_uid = from_kuid_munged(task_cred_xxx(tsk->parent, user_ns), task_uid(tsk)); rcu_read_unlock(); task_cputime(tsk, &utime, &stime); info.si_utime = cputime_to_clock_t(utime + tsk->signal->utime); info.si_stime = cputime_to_clock_t(stime + tsk->signal->stime); 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); if (!tsk->ptrace && sig == SIGCHLD && (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). */ autoreap = true; if (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) sig = 0; } if (valid_signal(sig) && sig) __group_send_sig_info(sig, &info, tsk->parent); __wake_up_parent(tsk, tsk->parent); spin_unlock_irqrestore(&psig->siglock, flags); return autoreap; }

Contributors

PersonTokensPropCommitsCommitProp
ingo molnaringo molnar22457.58%14.17%
roland mcgrathroland mcgrath4712.08%520.83%
oleg nesterovoleg nesterov369.25%312.50%
frederic weisbeckerfrederic weisbecker164.11%14.17%
peter zijlstrapeter zijlstra133.34%14.17%
eric w. biedermaneric w. biederman102.57%28.33%
pavel emelianovpavel emelianov102.57%14.17%
serge hallynserge hallyn82.06%14.17%
david howellsdavid howells51.29%28.33%
martin schwidefskymartin schwidefsky51.29%28.33%
tejun heotejun heo41.03%14.17%
matthew wilcoxmatthew wilcox30.77%14.17%
jesper juhljesper juhl30.77%14.17%
pavel machekpavel machek30.77%14.17%
linus torvaldslinus torvalds20.51%14.17%
Total389100.00%24100.00%

/** * 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) { struct siginfo info; unsigned long flags; struct task_struct *parent; struct sighand_struct *sighand; cputime_t utime, stime; if (for_ptracer) { parent = tsk->parent; } else { tsk = tsk->group_leader; parent = tsk->real_parent; } info.si_signo = SIGCHLD; info.si_errno = 0; /* * see comment in do_notify_parent() about the following 4 lines */ rcu_read_lock(); info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(parent)); info.si_uid = from_kuid_munged(task_cred_xxx(parent, user_ns), task_uid(tsk)); rcu_read_unlock(); task_cputime(tsk, &utime, &stime); info.si_utime = cputime_to_clock_t(utime); info.si_stime = cputime_to_clock_t(stime); 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); }

Contributors

PersonTokensPropCommitsCommitProp
ingo molnaringo molnar13045.94%16.67%
roland mcgrathroland mcgrath4917.31%213.33%
oleg nesterovoleg nesterov3010.60%16.67%
frederic weisbeckerfrederic weisbecker165.65%16.67%
linus torvaldslinus torvalds155.30%16.67%
pavel emelianovpavel emelianov103.53%16.67%
eric w. biedermaneric w. biederman93.18%213.33%
serge hallynserge hallyn72.47%16.67%
tejun heotejun heo62.12%16.67%
david howellsdavid howells41.41%16.67%
martin schwidefskymartin schwidefsky41.41%16.67%
michael kerriskmichael kerrisk20.71%16.67%
randy dunlaprandy dunlap10.35%16.67%
Total283100.00%15100.00%


static inline int may_ptrace_stop(void) { if (!likely(current->ptrace)) return 0; /* * 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 * ->siglock we must see ->core_state != NULL. Otherwise it * is safe to enter schedule(). * * This is almost outdated, a task with the pending SIGKILL can't * block in TASK_TRACED. But PTRACE_EVENT_EXIT can be reported * after SIGKILL was already dequeued. */ if (unlikely(current->mm->core_state) && unlikely(current->mm == current->parent->mm)) return 0; return 1; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov5196.23%375.00%
tejun heotejun heo23.77%125.00%
Total53100.00%4100.00%

/* * Return non-zero if there is a SIGKILL that should be waking us up. * Called with the siglock held. */
static int sigkill_pending(struct task_struct *tsk) { return sigismember(&tsk->pending.signal, SIGKILL) || sigismember(&tsk->signal->shared_pending.signal, SIGKILL); }

Contributors

PersonTokensPropCommitsCommitProp
roland mcgrathroland mcgrath38100.00%1100.00%
Total38100.00%1100.00%

/* * 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. * * If we actually decide not to stop at all because the tracer * is gone, we keep current->exit_code unless clear_code. */
static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info) __releases(&current->sighand->siglock

Contributors

PersonTokensPropCommitsCommitProp
roland mcgrathroland mcgrath1365.00%240.00%
tejun heotejun heo315.00%120.00%
namhyung kimnamhyung kim315.00%120.00%
oleg nesterovoleg nesterov15.00%120.00%
Total20100.00%5100.00%

) __acquires(&current->sighand->siglock) { bool gstop_done = false; 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(&current->sighand->siglock); arch_ptrace_stop(exit_code, info); spin_lock_irq(&current->sighand->siglock); if (sigkill_pending(current)) return; } /* * 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. */ set_current_state(TASK_TRACED); current->last_siginfo = info; current->exit_code = exit_code; /* * If @why is CLD_STOPPED, we're trapping to participate in a group * stop. Do the bookkeeping. Note that if SIGCONT was delievered * 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. */ if (why == CLD_STOPPED && (current->jobctl & JOBCTL_STOP_PENDING)) gstop_done = task_participate_group_stop(current); /* any trap clears pending STOP trap, STOP trap clears NOTIFY */ task_clear_jobctl_pending(current, JOBCTL_TRAP_STOP); if (info && info->si_code >> 8 == PTRACE_EVENT_STOP) task_clear_jobctl_pending(current, JOBCTL_TRAP_NOTIFY); /* entering a trap, clear TRAPPING */ task_clear_jobctl_trapping(current); spin_unlock_irq(&current->sighand->siglock); read_lock(&tasklist_lock); if (may_ptrace_stop()) { /* * 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); if (gstop_done && ptrace_reparented(current)) do_notify_parent_cldstop(current, false, why); /* * Don't want to allow preemption here, because * sys_ptrace() needs this task to be inactive. * * XXX: implement read_unlock_no_resched(). */ preempt_disable(); read_unlock(&tasklist_lock); preempt_enable_no_resched(); freezable_schedule(); } else { /* * By the time we got the lock, our tracer went away. * Don't drop the lock yet, another tracer may come. * * If @gstop_done, the ptracer went away between group stop * completion and here. During detach, it would have set * 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. */ if (gstop_done) do_notify_parent_cldstop(current, false, why); /* tasklist protects us from ptrace_freeze_traced() */ __set_current_state(TASK_RUNNING); if (clear_code) current->exit_code = 0; read_unlock(&tasklist_lock); } /* * 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(&current->sighand->siglock); current->last_siginfo = NULL; /* LISTENING can be set only during STOP traps, clear it */ current->jobctl &= ~JOBCTL_LISTENING; /* * Queued signals ignored us while we were stopped for tracing. * So check for any that we should take before resuming user mode. * This sets TIF_SIGPENDING, but never clears it. */ recalc_sigpending_tsk(current); }
static void ptrace_do_notify(int signr, int exit_code, int why) { siginfo_t info; memset(&info, 0, sizeof info); info.si_signo = signr; info.si_code = exit_code; info.si_pid = task_pid_vnr(current); info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); /* Let the debugger run. */ ptrace_stop(exit_code, why, 1, &info); }

Contributors

PersonTokensPropCommitsCommitProp
roland mcgrathroland mcgrath4356.58%120.00%
tejun heotejun heo2228.95%120.00%
eric w. biedermaneric w. biederman67.89%120.00%
pavel emelianovpavel emelianov33.95%120.00%
david howellsdavid howells22.63%120.00%
Total76100.00%5100.00%


void ptrace_notify(int exit_code) { BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP); if (unlikely(current->task_works)) task_work_run(); spin_lock_irq(&current->sighand->siglock); ptrace_do_notify(SIGTRAP, exit_code, CLD_TRAPPED); spin_unlock_irq(&current->sighand->siglock); }

Contributors

PersonTokensPropCommitsCommitProp
tejun heotejun heo2741.54%250.00%
roland mcgrathroland mcgrath2640.00%125.00%
al viroal viro1218.46%125.00%
Total65100.00%4100.00%

/** * 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. */
static bool do_signal_stop(int signr) __releases(&current->sighand->siglock

Contributors

PersonTokensPropCommitsCommitProp
tejun heotejun heo440.00%133.33%
ingo molnaringo molnar330.00%133.33%
pre-gitpre-git330.00%133.33%
Total10100.00%3100.00%

) { struct signal_struct *sig = current->signal; if (!(current->jobctl & JOBCTL_STOP_PENDING)) { unsigned long gstop = JOBCTL_STOP_PENDING | JOBCTL_STOP_CONSUME; struct task_struct *t; /* signr will be recorded in task->jobctl for retries */ WARN_ON_ONCE(signr & ~JOBCTL_STOP_SIGMASK); if (!likely(current->jobctl & JOBCTL_STOP_DEQUEUED) || unlikely(signal_group_exit(sig))) return false; /* * 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 * cause two group stops when !ptraced. That is why we * also check !task_is_stopped(t) below. * * 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. */ if (!(sig->flags & SIGNAL_STOP_STOPPED)) sig->group_exit_code = signr; sig->group_stop_count = 0; if (task_set_jobctl_pending(current, signr | gstop)) sig->group_stop_count++; t = current; while_each_thread(current, t) { /* * Setting state to TASK_STOPPED for a group * stop is always done with the siglock held, * so this check has no races. */ if (!task_is_stopped(t) && task_set_jobctl_pending(t, signr | gstop)) { sig->group_stop_count++; if (likely(!(t->ptrace & PT_SEIZED))) signal_wake_up(t, 0); else ptrace_trap_notify(t); } } } if (likely(!current->ptrace)) { int notify = 0; /* * 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; __set_current_state(TASK_STOPPED); spin_unlock_irq(&current->sighand->siglock); /* * 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. */ if (notify) { read_lock(&tasklist_lock); do_notify_parent_cldstop(current, false, notify); read_unlock(&tasklist_lock); } /* Now we don't run again until woken by SIGCONT or SIGKILL */ freezable_schedule(); return true; } else { /* * 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; } } /** * do_jobctl_trap - take care of ptrace jobctl traps * * 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. * * 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) { struct signal_struct *signal = current->signal; int signr = current->jobctl & JOBCTL_STOP_SIGMASK; 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; } }

Contributors

PersonTokensPropCommitsCommitProp
tejun heotejun heo9491.26%571.43%
roland mcgrathroland mcgrath87.77%114.29%
ingo molnaringo molnar10.97%114.29%
Total103100.00%7100.00%


static int ptrace_signal(int signr, siginfo_t *info) { ptrace_signal_deliver(); /* * 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; ptrace_stop(signr, CLD_TRAPPED, 0, info); /* We're back. Did the debugger cancel the sig? */ signr = current->exit_code; if (signr == 0) return signr; current->exit_code = 0; /* * 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. */ if (signr != info->si_signo) { info->si_signo = signr; info->si_errno = 0; info->si_code = SI_USER; rcu_read_lock(); info->si_pid = task_pid_vnr(current->parent); info->si_uid = from_kuid_munged(current_user_ns(), task_uid(current->parent)); rcu_read_unlock(); } /* If the (new) signal is now blocked, requeue it. */ if (sigismember(&current->blocked, signr)) { specific_send_sig_info(signr, info, current); signr = 0; } return signr; }

Contributors

PersonTokensPropCommitsCommitProp
stephen rothwellstephen rothwell8959.33%16.25%
roland mcgrathroland mcgrath2114.00%425.00%
ingo molnaringo molnar85.33%16.25%
oleg nesterovoleg nesterov85.33%212.50%
serge hallynserge hallyn85.33%16.25%
eric w. biedermaneric w. biederman53.33%16.25%
pavel emelianovpavel emelianov32.00%16.25%
david howellsdavid howells21.33%16.25%
tejun heotejun heo21.33%16.25%
david s. millerdavid s. miller21.33%16.25%
al viroal viro10.67%16.25%
randy dunlaprandy dunlap10.67%16.25%
Total150100.00%16100.00%


int get_signal(struct ksignal *ksig) { struct sighand_struct *sighand = current->sighand; struct signal_struct *signal = current->signal; int signr; if (unlikely(current->task_works)) task_work_run(); if (unlikely(uprobe_deny_signal())) return 0; /* * Do this once, we can't return to user-mode if freezing() == T. * do_signal_stop() and ptrace_stop() do freezable_schedule() and * thus do not need another check after return. */ try_to_freeze(); relock: spin_lock_irq(&sighand->siglock); /* * 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. */ if (unlikely(signal->flags & SIGNAL_CLD_MASK)) { int why; if (signal->flags & SIGNAL_CLD_CONTINUED) why = CLD_CONTINUED; else why = CLD_STOPPED; signal->flags &= ~SIGNAL_CLD_MASK; spin_unlock_irq(&sighand->siglock); /* * 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. */ read_lock(&tasklist_lock); do_notify_parent_cldstop(current, false, why); if (ptrace_reparented(current->group_leader)) do_notify_parent_cldstop(current->group_leader, true, why); read_unlock(&tasklist_lock); goto relock; } for (;;) { struct k_sigaction *ka; if (unlikely(current->jobctl & JOBCTL_STOP_PENDING) && do_signal_stop(0)) goto relock; if (unlikely(current->jobctl & JOBCTL_TRAP_MASK)) { do_jobctl_trap(); spin_unlock_irq(&sighand->siglock); goto relock; } signr = dequeue_signal(current, &current->blocked, &ksig->info); if (!signr) break; /* will return 0 */ if (unlikely(current->ptrace) && signr != SIGKILL) { signr = ptrace_signal(signr, &ksig->info); if (!signr) continue; } ka = &sighand->action[signr-1]; /* Trace actually delivered signals. */ trace_signal_deliver(signr, &ksig->info, ka); if (ka->sa.sa_handler == SIG_IGN) /* Do nothing. */ continue; if (ka->sa.sa_handler != SIG_DFL) { /* Run the handler. */ ksig->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; /* * Global init gets no signals it doesn't want. * 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. */ if (unlikely(signal->flags & SIGNAL_UNKILLABLE) && !sig_kernel_only(signr)) 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) { spin_unlock_irq(&sighand->siglock); /* signals can be posted during this window */ if (is_current_pgrp_orphaned()) goto relock; spin_lock_irq(&sighand->siglock); } if (likely(do_signal_stop(ksig->info.si_signo))) { /* It released the siglock. */ goto relock; } /* * We didn't actually stop, due to a race * with SIGCONT or something like that. */ continue; } spin_unlock_irq(&sighand->siglock); /* * Anything else is fatal, maybe with a core dump. */ current->flags |= PF_SIGNALED; if (sig_kernel_coredump(signr)) { if (print_fatal_signals) print_fatal_signal(ksig->info.si_signo); proc_coredump_connector(current); /* * 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. */ do_coredump(&ksig->info); } /* * Death signals, no core dump. */ do_group_exit(ksig->info.si_signo); /* NOTREACHED */ } spin_unlock_irq(&sighand->siglock); ksig->sig = signr; return ksig->sig > 0; }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov12222.98%927.27%
roland mcgrathroland mcgrath10720.15%412.12%
stephen rothwellstephen rothwell5610.55%13.03%
andrew mortonandrew morton509.42%13.03%
tejun heotejun heo489.04%618.18%
ingo molnaringo molnar407.53%26.06%
richard weinbergerrichard weinberger387.16%13.03%
corey minyardcorey minyard244.52%13.03%
al viroal viro122.26%13.03%
srikar dronamrajusrikar dronamraju112.07%13.03%
masami hiramatsumasami hiramatsu101.88%13.03%
sukadev bhattiprolusukadev bhattiprolu50.94%26.06%
jesper derehagjesper derehag50.94%13.03%
eric w. biedermaneric w. biederman20.38%13.03%
linus torvaldslinus torvalds10.19%13.03%
Total531100.00%33100.00%

/** * signal_delivered - * @ksig: kernel signal struct * @stepping: nonzero if debugger single-step or block-step in use * * This function should be called when a signal has successfully been * delivered. It updates the blocked signals accordingly (@ksig->ka.sa.sa_mask * is always blocked, and the signal itself is blocked unless %SA_NODEFER * is set in @ksig->ka.sa.sa_flags. Tracing is notified. */
static void signal_delivered(struct ksignal *ksig, int stepping) { sigset_t blocked; /* A signal was successfully delivered, and the saved sigmask was stored on the signal frame, and will be restored by sigreturn. So we can simply clear the restore sigmask flag. */ clear_restore_sigmask(); sigorsets(&blocked, &current->blocked, &ksig->ka.sa.sa_mask); if (!(ksig->ka.sa.sa_flags & SA_NODEFER)) sigaddset(&blocked, ksig->sig); set_current_blocked(&blocked); tracehook_signal_handler(stepping); }

Contributors

PersonTokensPropCommitsCommitProp
matt flemingmatt fleming5166.23%125.00%
al viroal viro1519.48%250.00%
richard weinbergerrichard weinberger1114.29%125.00%
Total77100.00%4100.00%


void signal_setup_done(int failed, struct ksignal *ksig, int stepping) { if (failed) force_sigsegv(ksig->sig, current); else signal_delivered(ksig, stepping); }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro37100.00%1100.00%
Total37100.00%1100.00%

/* * It could be that complete_signal() picked us to notify about the * group-wide signal. Other threads should be notified now to take * the shared signals in @which since we will not. */
static void retarget_shared_pending(struct task_struct *tsk, sigset_t *which) { sigset_t retarget; struct task_struct *t; sigandsets(&retarget, &tsk->signal->shared_pending.signal, which); if (sigisemptyset(&retarget)) return; t = tsk; while_each_thread(tsk, t) { 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; } }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov124100.00%3100.00%
Total124100.00%3100.00%


void exit_signals(struct task_struct *tsk) { int group_stop = 0; sigset_t unblocked; /* * @tsk is about to have PF_EXITING set - lock out users which * expect stable threadgroup. */ threadgroup_change_begin(tsk); if (thread_group_empty(tsk) || signal_group_exit(tsk->signal)) { tsk->flags |= PF_EXITING; threadgroup_change_end(tsk); return; } spin_lock_irq(&tsk->sighand->siglock); /* * From now this task is not visible for group-wide signals, * see wants_signal(), do_signal_stop(). */ tsk->flags |= PF_EXITING; threadgroup_change_end(tsk); if (!signal_pending(tsk)) goto out; unblocked = tsk->blocked; signotset(&unblocked); retarget_shared_pending(tsk, &unblocked); if (unlikely(tsk->jobctl & JOBCTL_STOP_PENDING) && task_participate_group_stop(tsk)) group_stop = CLD_STOPPED; out: spin_unlock_irq(&tsk->sighand->siglock); /* * If group stop has completed, deliver the notification. This * should always go to the real parent of the group leader. */ if (unlikely(group_stop)) { read_lock(&tasklist_lock); do_notify_parent_cldstop(tsk, false, group_stop); read_unlock(&tasklist_lock); } }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov14183.93%436.36%
tejun heotejun heo2514.88%654.55%
roland mcgrathroland mcgrath21.19%19.09%
Total168100.00%11100.00%

EXPORT_SYMBOL(recalc_sigpending); EXPORT_SYMBOL_GPL(dequeue_signal); EXPORT_SYMBOL(flush_signals); EXPORT_SYMBOL(force_sig); EXPORT_SYMBOL(send_sig); EXPORT_SYMBOL(send_sig_info); EXPORT_SYMBOL(sigprocmask); /* * System call entry points. */ /** * sys_restart_syscall - restart a system call */ SYSCALL_DEFINE0(restart_syscall) { struct restart_block *restart = &current->restart_block; return restart->fn(restart); }
long do_no_restart_syscall(struct restart_block *param) { return -EINTR; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds14100.00%1100.00%
Total14100.00%1100.00%


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. */ sigandnsets(&newblocked, newset, &current->blocked); retarget_shared_pending(tsk, &newblocked); } tsk->blocked = *newset; recalc_sigpending(); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov66100.00%3100.00%
Total66100.00%3100.00%

/** * 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. */
void set_current_blocked(sigset_t *newset) { sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP)); __set_current_blocked(newset); }

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PersonTokensPropCommitsCommitProp
al viroal viro2586.21%133.33%
oleg nesterovoleg nesterov413.79%266.67%
Total29100.00%3100.00%


void __set_current_blocked(const sigset_t *newset) { struct task_struct *tsk = current; /* * In case the signal mask hasn't changed, there is nothing we need * to do. The current->blocked shouldn't be modified by other task. */ if (sigequalsets(&tsk->blocked, newset)) return; spin_lock_irq(&tsk->sighand->siglock); __set_task_blocked(tsk, newset); spin_unlock_irq(&tsk->sighand->siglock); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov4170.69%250.00%
waiman longwaiman long1424.14%125.00%
al viroal viro35.17%125.00%
Total58100.00%4100.00%

/* * 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) { struct task_struct *tsk = current; sigset_t newset; /* Lockless, only current can change ->blocked, never from irq */ if (oldset) *oldset = tsk->blocked; switch (how) { case SIG_BLOCK: sigorsets(&newset, &tsk->blocked, set); break; case SIG_UNBLOCK: sigandnsets(&newset, &tsk->blocked, set); break; case SIG_SETMASK: newset = *set; break; default: return -EINVAL; } __set_current_blocked(&newset); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds7372.28%233.33%
oleg nesterovoleg nesterov2726.73%350.00%
al viroal viro10.99%116.67%
Total101100.00%6100.00%

/** * sys_rt_sigprocmask - change the list of currently blocked signals * @how: whether to add, remove, or set signals * @nset: stores pending signals * @oset: previous value of signal mask if non-null * @sigsetsize: size of sigset_t type */ SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, nset, sigset_t __user *, oset, size_t, sigsetsize) { sigset_t old_set, new_set; int error; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; old_set = current->blocked; if (nset) { if (copy_from_user(&new_set, nset, sizeof(sigset_t))) return -EFAULT; sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); error = sigprocmask(how, &new_set, NULL); if (error) return error; } if (oset) { if (copy_to_user(oset, &old_set, sizeof(sigset_t))) return -EFAULT; } return 0; } #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, compat_sigset_t __user *, oset, compat_size_t, sigsetsize) { #ifdef __BIG_ENDIAN sigset_t old_set = current->blocked; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; if (nset) { compat_sigset_t new32; sigset_t new_set; int error; if (copy_from_user(&new32, nset, sizeof(compat_sigset_t))) return -EFAULT; sigset_from_compat(&new_set, &new32); sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); error = sigprocmask(how, &new_set, NULL); if (error) return error; } if (oset) { compat_sigset_t old32; sigset_to_compat(&old32, &old_set); if (copy_to_user(oset, &old32, sizeof(compat_sigset_t))) return -EFAULT; } return 0; #else return sys_rt_sigprocmask(how, (sigset_t __user *)nset, (sigset_t __user *)oset, sigsetsize); #endif } #endif
static int do_sigpending(void *set, unsigned long sigsetsize) { if (sigsetsize > sizeof(sigset_t)) return -EINVAL; spin_lock_irq(&current->sighand->siglock); sigorsets(set, &current->pending.signal, &current->signal->shared_pending.signal); spin_unlock_irq(&current->sighand->siglock); /* Outside the lock because only this thread touches it. */ sigandsets(set, &current->blocked, set); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git4755.95%342.86%
ingo molnaringo molnar2125.00%228.57%
al viroal viro1315.48%114.29%
linus torvaldslinus torvalds33.57%114.29%
Total84100.00%7100.00%

/** * sys_rt_sigpending - examine a pending signal that has been raised * while blocked * @uset: stores pending signals * @sigsetsize: size of sigset_t type or larger */ SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize) { sigset_t set; int err = do_sigpending(&set, sigsetsize); if (!err && copy_to_user(uset, &set, sigsetsize)) err = -EFAULT; return err; } #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset, compat_size_t, sigsetsize) { #ifdef __BIG_ENDIAN sigset_t set; int err = do_sigpending(&set, sigsetsize); if (!err) { compat_sigset_t set32; sigset_to_compat(&set32, &set); /* we can get here only if sigsetsize <= sizeof(set) */ if (copy_to_user(uset, &set32, sigsetsize)) err = -EFAULT; } return err; #else return sys_rt_sigpending((sigset_t __user *)uset, sigsetsize); #endif } #endif #ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER
int copy_siginfo_to_user(siginfo_t __user *to, const 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. * Please remember to update the signalfd_copyinfo() function * inside fs/signalfd.c too, in case siginfo_t changes. * 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 #ifdef BUS_MCEERR_AO /* * Other callers might not initialize the si_lsb field, * so check explicitly for the right codes here. */ if (from->si_signo == SIGBUS && (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO)) err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); #endif #ifdef SEGV_BNDERR if (from->si_signo == SIGSEGV && from->si_code == SEGV_BNDERR) { err |= __put_user(from->si_lower, &to->si_lower); err |= __put_user(from->si_upper, &to->si_upper); } #endif #ifdef SEGV_PKUERR if (from->si_signo == SIGSEGV && from->si_code == SEGV_PKUERR) err |= __put_user(from->si_pkey, &to->si_pkey); #endif 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; #ifdef __ARCH_SIGSYS case __SI_SYS: err |= __put_user(from->si_call_addr, &to->si_call_addr); err |= __put_user(from->si_syscall, &to->si_syscall); err |= __put_user(from->si_arch, &to->si_arch); break; #endif 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; }

Contributors

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stephen rothwellstephen rothwell40066.67%321.43%
will drewrywill drewry518.50%17.14%
qiaowei renqiaowei ren335.50%17.14%
dave hansendave hansen335.50%17.14%
andi kleenandi kleen335.50%17.14%
amanieu d'antrasamanieu d'antras244.00%17.14%
george anzingergeorge anzinger183.00%17.14%
andrew mortonandrew morton40.67%17.14%
al viroal viro10.17%17.14%
randy dunlaprandy dunlap10.17%17.14%
davide libenzidavide libenzi10.17%17.14%
linus torvaldslinus torvalds10.17%17.14%
Total600100.00%14100.00%

#endif /** * 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) { ktime_t *to = NULL, timeout = KTIME_MAX; struct task_struct *tsk = current; sigset_t mask = *which; int sig, ret = 0; if (ts) { if (!timespec_valid(ts)) return -EINVAL; timeout = timespec_to_ktime(*ts); to = &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 * they arrive. Unblocking is always fine, we can avoid * set_current_blocked(). */ tsk->real_blocked = tsk->blocked; sigandsets(&tsk->blocked, &tsk->blocked, &mask); recalc_sigpending(); spin_unlock_irq(&tsk->sighand->siglock); __set_current_state(TASK_INTERRUPTIBLE); ret = freezable_schedule_hrtimeout_range(to, tsk->timer_slack_ns, HRTIMER_MODE_REL); spin_lock_irq(&tsk->sighand->siglock); __set_task_blocked(tsk, &tsk->real_blocked); sigemptyset(&tsk->real_blocked); sig = dequeue_signal(tsk, &mask, info); } spin_unlock_irq(&tsk->sighand->siglock); if (sig) return sig; return ret ? -EINTR : -EAGAIN; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git10239.69%535.71%
oleg nesterovoleg nesterov8633.46%428.57%
thomas gleixnerthomas gleixner3413.23%17.14%
ingo molnaringo molnar2810.89%17.14%
linus torvaldslinus torvalds62.33%214.29%
david s. millerdavid s. miller10.39%17.14%
Total257100.00%14100.00%

/** * 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 */ SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese, siginfo_t __user *, uinfo, const struct timespec __user *, uts, size_t, sigsetsize) { sigset_t these; struct timespec ts; siginfo_t info; int ret; /* 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; if (uts) { if (copy_from_user(&ts, uts, sizeof(ts))) return -EFAULT; } ret = do_sigtimedwait(&these, &info, uts ? &ts : NULL); if (ret > 0 && uinfo) { if (copy_siginfo_to_user(uinfo, &info)) ret = -EFAULT; } return ret; } /** * sys_kill - send a signal to a process * @pid: the PID of the process * @sig: signal to be sent */ SYSCALL_DEFINE2(kill, pid_t, pid, int, sig) { struct siginfo info; info.si_signo = sig; info.si_errno = 0; info.si_code = SI_USER; info.si_pid = task_tgid_vnr(current); info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); return kill_something_info(sig, &info, pid); }
static int do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info) { struct task_struct *p; int error = -ESRCH; rcu_read_lock(); p = find_task_by_vpid(pid); if (p && (tgid <= 0 || task_tgid_vnr(p) == tgid)) { error = check_kill_permission(sig, info, p); /* * The null signal is a permissions and process existence * probe. No signal is actually delivered. */ 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; } } rcu_read_unlock(); return error; }

Contributors

PersonTokensPropCommitsCommitProp
ulrich drepperulrich drepper7161.74%112.50%
oleg nesterovoleg nesterov2219.13%225.00%
vadim lobanovvadim lobanov86.96%112.50%
thomas gleixnerthomas gleixner86.96%112.50%
pavel emelianovpavel emelianov43.48%225.00%
gustavo padovangustavo padovan21.74%112.50%
Total115100.00%8100.00%


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 = from_kuid_munged(current_user_ns(), current_uid()); return do_send_specific(tgid, pid, sig, &info); }

Contributors

PersonTokensPropCommitsCommitProp
thomas gleixnerthomas gleixner6689.19%133.33%
eric w. biedermaneric w. biederman68.11%133.33%
emese revfyemese revfy22.70%133.33%
Total74100.00%3100.00%

/** * 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 * * This syscall also checks the @tgid and returns -ESRCH even if the PID * exists but it's not belonging to the target process anymore. This * method solves the problem of threads exiting and PIDs getting reused. */ SYSCALL_DEFINE3(tgkill, pid_t, tgid, pid_t, pid, int, sig) { /* This is only valid for single tasks */ if (pid <= 0 || tgid <= 0) return -EINVAL; return do_tkill(tgid, pid, sig); } /** * sys_tkill - send signal to one specific task * @pid: the PID of the task * @sig: signal to be sent * * Send a signal to only one task, even if it's a CLONE_THREAD task. */ SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig) { /* This is only valid for single tasks */ if (pid <= 0) return -EINVAL; return do_tkill(0, pid, sig); }
static int do_rt_sigqueueinfo(pid_t pid, int sig, siginfo_t *info) { /* Not even root can pretend to send signals from the kernel. * Nor can they impersonate a kill()/tgkill(), which adds source info. */ if ((info->si_code >= 0 || info->si_code == SI_TKILL) && (task_pid_vnr(current) != pid)) return -EPERM; info->si_signo = sig; /* POSIX.1b doesn't mention process groups. */ return kill_proc_info(sig, info, pid); }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro5282.54%150.00%
andrey vaginandrey vagin1117.46%150.00%
Total63100.00%2100.00%

/** * 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 */ SYSCALL_DEFINE3(rt_sigqueueinfo, 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_sigqueueinfo(pid, sig, &info); } #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo, compat_pid_t, pid, int, sig, struct compat_siginfo __user *, uinfo) { siginfo_t info = {}; int ret = copy_siginfo_from_user32(&info, uinfo); if (unlikely(ret)) return ret; return do_rt_sigqueueinfo(pid, sig, &info); } #endif
static int 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. * Nor can they impersonate a kill()/tgkill(), which adds source info. */ if ((info->si_code >= 0 || info->si_code == SI_TKILL) && (task_pid_vnr(current) != pid)) return -EPERM; info->si_signo = sig; return do_send_specific(tgid, pid, sig, info); }

Contributors

PersonTokensPropCommitsCommitProp
thomas gleixnerthomas gleixner6073.17%120.00%
andrey vaginandrey vagin1113.41%120.00%
roland dreierroland dreier89.76%120.00%
al viroal viro22.44%120.00%
julien tinnesjulien tinnes11.22%120.00%
Total82100.00%5100.00%

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); } #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo, compat_pid_t, tgid, compat_pid_t, pid, int, sig, struct compat_siginfo __user *, uinfo) { siginfo_t info = {}; if (copy_siginfo_from_user32(&info, uinfo)) return -EFAULT; return do_rt_tgsigqueueinfo(tgid, pid, sig, &info); } #endif /* * For kthreads only, must not be used if cloned with CLONE_SIGHAND */
void kernel_sigaction(int sig, __sighandler_t action) { spin_lock_irq(&current->sighand->siglock); current->sighand->action[sig - 1].sa.sa_handler = action; if (action == SIG_IGN) { sigset_t mask; sigemptyset(&mask); sigaddset(&mask, sig); flush_sigqueue_mask(&mask, &current->signal->shared_pending); flush_sigqueue_mask(&mask, &current->pending); recalc_sigpending(); } spin_unlock_irq(&current->sighand->siglock); }

Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov100100.00%3100.00%
Total100100.00%3100.00%

EXPORT_SYMBOL(kernel_sigaction);
void __weak sigaction_compat_abi(struct k_sigaction *act, struct k_sigaction *oact) { }

Contributors

PersonTokensPropCommitsCommitProp
dmitry safonovdmitry safonov15100.00%1100.00%
Total15100.00%1100.00%


int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) { struct task_struct *p = current, *t; struct k_sigaction *k; sigset_t mask; if (!valid_signal(sig) || sig < 1 || (act && sig_kernel_only(sig))) return -EINVAL; k = &p->sighand->action[sig-1]; spin_lock_irq(&p->sighand->siglock); if (oact) *oact = *k; sigaction_compat_abi(act, oact); if (act) { sigdelsetmask(&act->sa.sa_mask, sigmask(SIGKILL) | sigmask(SIGSTOP)); *k = *act; /* * 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" */ if (sig_handler_ignored(sig_handler(p, sig), sig)) { sigemptyset(&mask); sigaddset(&mask, sig); flush_sigqueue_mask(&mask, &p->signal->shared_pending); for_each_thread(p, t) flush_sigqueue_mask(&mask, &t->pending); } } spin_unlock_irq(&p->sighand->siglock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git7937.98%422.22%
oleg nesterovoleg nesterov4521.63%422.22%
ingo molnaringo molnar2311.06%211.11%
george anzingergeorge anzinger188.65%15.56%
roland mcgrathroland mcgrath188.65%211.11%
pavel emelianovpavel emelianov73.37%15.56%
dmitry safonovdmitry safonov73.37%15.56%
jesper juhljesper juhl62.88%15.56%
linus torvaldslinus torvalds52.40%211.11%
Total208100.00%18100.00%


static int do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long sp) { stack_t oss; int error; oss.ss_sp = (void __user *) current->sas_ss_sp; oss.ss_size = current->sas_ss_size; oss.ss_flags = sas_ss_flags(sp) | (current->sas_ss_flags & SS_FLAG_BITS); if (uss) { void __user *ss_sp; size_t ss_size; unsigned ss_flags; int ss_mode; error = -EFAULT; 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) goto out; error = -EPERM; if (on_sig_stack(sp)) goto out; ss_mode = ss_flags & ~SS_FLAG_BITS; error = -EINVAL; if (ss_mode != SS_DISABLE && ss_mode != SS_ONSTACK && ss_mode != 0) goto out; if (ss_mode == 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; current->sas_ss_flags = ss_flags; } error = 0; if (uoss) { error = -EFAULT; if (!access_ok(VERIFY_WRITE, uoss, sizeof(*uoss))) goto out; 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); } out: return error; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git23070.99%218.18%
linus torvaldslinus torvalds6219.14%436.36%
stas sergeevstas sergeev216.48%218.18%
andy lutomirskiandy lutomirski82.47%19.09%
jesper juhljesper juhl20.62%19.09%
oleg nesterovoleg nesterov10.31%19.09%
Total324100.00%11100.00%

SYSCALL_DEFINE2(sigaltstack,const stack_t __user *,uss, stack_t __user *,uoss) { return do_sigaltstack(uss, uoss, current_user_stack_pointer()); }
int restore_altstack(const stack_t __user *uss) { int err = do_sigaltstack(uss, NULL, current_user_stack_pointer()); /* squash all but EFAULT for now */ return err == -EFAULT ? err : 0; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro35100.00%1100.00%
Total35100.00%1100.00%


int __save_altstack(stack_t __user *uss, unsigned long sp) { struct task_struct *t = current; int err = __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) | __put_user(t->sas_ss_flags, &uss->ss_flags) | __put_user(t->sas_ss_size, &uss->ss_size); if (err) return err; if (t->sas_ss_flags & SS_AUTODISARM) sas_ss_reset(t); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro6068.18%150.00%
stas sergeevstas sergeev2831.82%150.00%
Total88100.00%2100.00%

#ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(sigaltstack, const compat_stack_t __user *, uss_ptr, compat_stack_t __user *, uoss_ptr) { stack_t uss, uoss; int ret; mm_segment_t seg; if (uss_ptr) { compat_stack_t uss32; memset(&uss, 0, sizeof(stack_t)); if (copy_from_user(&uss32, uss_ptr, sizeof(compat_stack_t))) return -EFAULT; uss.ss_sp = compat_ptr(uss32.ss_sp); uss.ss_flags = uss32.ss_flags; uss.ss_size = uss32.ss_size; } seg = get_fs(); set_fs(KERNEL_DS); ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL), (stack_t __force __user *) &uoss, compat_user_stack_pointer()); set_fs(seg); if (ret >= 0 && uoss_ptr) { if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(compat_stack_t)) || __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) || __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) || __put_user(uoss.ss_size, &uoss_ptr->ss_size)) ret = -EFAULT; } return ret; }
int compat_restore_altstack(const compat_stack_t __user *uss) { int err = compat_sys_sigaltstack(uss, NULL); /* squash all but -EFAULT for now */ return err == -EFAULT ? err : 0; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro32100.00%1100.00%
Total32100.00%1100.00%


int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp) { struct task_struct *t = current; return __put_user(ptr_to_compat((void __user *)t->sas_ss_sp), &uss->ss_sp) | __put_user(sas_ss_flags(sp), &uss->ss_flags) | __put_user(t->sas_ss_size, &uss->ss_size); }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro67100.00%1100.00%
Total67100.00%1100.00%

#endif #ifdef __ARCH_WANT_SYS_SIGPENDING /** * sys_sigpending - examine pending signals * @set: where mask of pending signal is returned */ SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set) { return sys_rt_sigpending((sigset_t __user *)set, sizeof(old_sigset_t)); } #endif #ifdef __ARCH_WANT_SYS_SIGPROCMASK /** * sys_sigprocmask - examine and change blocked signals * @how: whether to add, remove, or set signals * @nset: signals to add or remove (if non-null) * @oset: previous value of signal mask if non-null * * Some platforms have their own version with special arguments; * others support only sys_rt_sigprocmask. */ SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset, old_sigset_t __user *, oset) { old_sigset_t old_set, new_set; sigset_t new_blocked; old_set = current->blocked.sig[0]; if (nset) { if (copy_from_user(&new_set, nset, sizeof(*nset))) return -EFAULT; new_blocked = current->blocked; switch (how) { case SIG_BLOCK: sigaddsetmask(&new_blocked, new_set); break; case SIG_UNBLOCK: sigdelsetmask(&new_blocked, new_set); break; case SIG_SETMASK: new_blocked.sig[0] = new_set; break; default: return -EINVAL; } set_current_blocked(&new_blocked); } if (oset) { if (copy_to_user(oset, &old_set, sizeof(*oset))) return -EFAULT; } return 0; } #endif /* __ARCH_WANT_SYS_SIGPROCMASK */ #ifndef CONFIG_ODD_RT_SIGACTION /** * sys_rt_sigaction - alter an action taken by a process * @sig: signal to be sent * @act: new sigaction * @oact: used to save the previous sigaction * @sigsetsize: size of sigset_t type */ SYSCALL_DEFINE4(rt_sigaction, int, sig, const struct sigaction __user *, act, struct sigaction __user *, oact, size_t, sigsetsize) { 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; } #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, const struct compat_sigaction __user *, act, struct compat_sigaction __user *, oact, compat_size_t, sigsetsize) { struct k_sigaction new_ka, old_ka; compat_sigset_t mask; #ifdef __ARCH_HAS_SA_RESTORER compat_uptr_t restorer; #endif int ret; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(compat_sigset_t)) return -EINVAL; if (act) { compat_uptr_t handler; ret = get_user(handler, &act->sa_handler); new_ka.sa.sa_handler = compat_ptr(handler); #ifdef __ARCH_HAS_SA_RESTORER ret |= get_user(restorer, &act->sa_restorer); new_ka.sa.sa_restorer = compat_ptr(restorer); #endif ret |= copy_from_user(&mask, &act->sa_mask, sizeof(mask)); ret |= get_user(new_ka.sa.sa_flags, &act->sa_flags); if (ret) return -EFAULT; sigset_from_compat(&new_ka.sa.sa_mask, &mask); } ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); if (!ret && oact) { sigset_to_compat(&mask, &old_ka.sa.sa_mask); ret = put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler); ret |= copy_to_user(&oact->sa_mask, &mask, sizeof(mask)); ret |= put_user(old_ka.sa.sa_flags, &oact->sa_flags); #ifdef __ARCH_HAS_SA_RESTORER ret |= put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer); #endif } return ret; } #endif #endif /* !CONFIG_ODD_RT_SIGACTION */ #ifdef CONFIG_OLD_SIGACTION SYSCALL_DEFINE3(sigaction, int, sig, const struct old_sigaction __user *, act, struct old_sigaction __user *, oact) { struct k_sigaction new_ka, old_ka; int ret; if (act) { old_sigset_t mask; if (!access_ok(VERIFY_READ, act, sizeof(*act)) || __get_user(new_ka.sa.sa_handler, &act->sa_handler) || __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) || __get_user(new_ka.sa.sa_flags, &act->sa_flags) || __get_user(mask, &act->sa_mask)) return -EFAULT; #ifdef __ARCH_HAS_KA_RESTORER new_ka.ka_restorer = NULL; #endif siginitset(&new_ka.sa.sa_mask, mask); } ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); if (!ret && oact) { if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) || __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) return -EFAULT; } return ret; } #endif #ifdef CONFIG_COMPAT_OLD_SIGACTION COMPAT_SYSCALL_DEFINE3(sigaction, int, sig, const struct compat_old_sigaction __user *, act, struct compat_old_sigaction __user *, oact) { struct k_sigaction new_ka, old_ka; int ret; compat_old_sigset_t mask; compat_uptr_t handler, restorer; if (act) { if (!access_ok(VERIFY_READ, act, sizeof(*act)) || __get_user(handler, &act->sa_handler) || __get_user(restorer, &act->sa_restorer) || __get_user(new_ka.sa.sa_flags, &act->sa_flags) || __get_user(mask, &act->sa_mask)) return -EFAULT; #ifdef __ARCH_HAS_KA_RESTORER new_ka.ka_restorer = NULL; #endif new_ka.sa.sa_handler = compat_ptr(handler); new_ka.sa.sa_restorer = compat_ptr(restorer); siginitset(&new_ka.sa.sa_mask, mask); } ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); if (!ret && oact) { if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || __put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler) || __put_user(ptr_to_compat(old_ka.sa.sa_restorer), &oact->sa_restorer) || __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) return -EFAULT; } return ret; } #endif #ifdef CONFIG_SGETMASK_SYSCALL /* * For backwards compatibility. Functionality superseded by sigprocmask. */ SYSCALL_DEFINE0(sgetmask) { /* SMP safe */ return current->blocked.sig[0]; } SYSCALL_DEFINE1(ssetmask, int, newmask) { int old = current->blocked.sig[0]; sigset_t newset; siginitset(&newset, newmask); set_current_blocked(&newset); return old; } #endif /* CONFIG_SGETMASK_SYSCALL */ #ifdef __ARCH_WANT_SYS_SIGNAL /* * For backwards compatibility. Functionality superseded by sigaction. */ SYSCALL_DEFINE2(signal, int, sig, __sighandler_t, handler) { struct k_sigaction new_sa, old_sa; int ret; new_sa.sa.sa_handler = handler; new_sa.sa.sa_flags = SA_ONESHOT | SA_NOMASK; sigemptyset(&new_sa.sa.sa_mask); 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 SYSCALL_DEFINE0(pause) { while (!signal_pending(current)) { __set_current_state(TASK_INTERRUPTIBLE); schedule(); } return -ERESTARTNOHAND; } #endif
static int sigsuspend(sigset_t *set) { current->saved_sigmask = current->blocked; set_current_blocked(set); while (!signal_pending(current)) { __set_current_state(TASK_INTERRUPTIBLE); schedule(); } set_restore_sigmask(); return -ERESTARTNOHAND; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro3470.83%125.00%
sasha levinsasha levin1020.83%125.00%
davidlohr buesodavidlohr bueso36.25%125.00%
richard weinbergerrichard weinberger12.08%125.00%
Total48100.00%4100.00%

/** * 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 */ SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *, unewset, size_t, sigsetsize) { 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; return sigsuspend(&newset); } #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(rt_sigsuspend, compat_sigset_t __user *, unewset, compat_size_t, sigsetsize) { #ifdef __BIG_ENDIAN sigset_t newset; compat_sigset_t newset32; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t))) return -EFAULT; sigset_from_compat(&newset, &newset32); return sigsuspend(&newset); #else /* on little-endian bitmaps don't care about granularity */ return sys_rt_sigsuspend((sigset_t __user *)unewset, sigsetsize); #endif } #endif #ifdef CONFIG_OLD_SIGSUSPEND SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask) { sigset_t blocked; siginitset(&blocked, mask); return sigsuspend(&blocked); } #endif #ifdef CONFIG_OLD_SIGSUSPEND3 SYSCALL_DEFINE3(sigsuspend, int, unused1, int, unused2, old_sigset_t, mask) { sigset_t blocked; siginitset(&blocked, mask); return sigsuspend(&blocked); } #endif
__weak const char *arch_vma_name(struct vm_area_struct *vma) { return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
david howellsdavid howells1593.75%150.00%
gideon israel dsouzagideon israel dsouza16.25%150.00%
Total16100.00%2100.00%


void __init signals_init(void) { /* If this check fails, the __ARCH_SI_PREAMBLE_SIZE value is wrong! */ BUILD_BUG_ON(__ARCH_SI_PREAMBLE_SIZE != offsetof(struct siginfo, _sifields._pad)); sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC); }

Contributors

PersonTokensPropCommitsCommitProp
helge dellerhelge deller1648.48%125.00%
ingo molnaringo molnar1545.45%125.00%
andrew mortonandrew morton13.03%125.00%
christoph lameterchristoph lameter13.03%125.00%
Total33100.00%4100.00%

#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.\n" "The sigmask lock is held somewhere else in " "kernel, try again later\n"); 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\n" "on the run queue locks. " "The signal has _not_ been sent.\n" "Reissue the kill command if you want to risk " "the deadlock.\n"); return; } sig = info->si_signo; if (send_sig_info(sig, info, t)) kdb_printf("Fail to deliver Signal %d to process %d.\n", sig, t->pid); else kdb_printf("Signal %d is sent to process %d.\n", sig, t->pid); }

Contributors

PersonTokensPropCommitsCommitProp
jason wesseljason wessel132100.00%1100.00%
Total132100.00%1100.00%

#endif /* CONFIG_KGDB_KDB */

Overall Contributors

PersonTokensPropCommitsCommitProp
oleg nesterovoleg nesterov285220.18%10724.43%
al viroal viro206414.60%286.39%
pre-gitpre-git165511.71%409.13%
ingo molnaringo molnar8816.23%112.51%
tejun heotejun heo8636.10%276.16%
roland mcgrathroland mcgrath7765.49%255.71%
stephen rothwellstephen rothwell5724.05%51.14%
jim houstonjim houston5724.05%10.23%
linus torvaldslinus torvalds4943.49%286.39%
thomas gleixnerthomas gleixner3222.28%61.37%
serge hallynserge hallyn2811.99%40.91%
pavel emelianovpavel emelianov2671.89%122.74%
eric w. biedermaneric w. biederman2381.68%92.05%
william lee irwin iiiwilliam lee irwin iii1991.41%10.23%
heiko carstensheiko carstens1751.24%51.14%
george anzingergeorge anzinger1671.18%20.46%
jason wesseljason wessel1421.00%10.23%
sukadev bhattiprolusukadev bhattiprolu1110.79%81.83%
harald welteharald welte1110.79%10.23%
andrew mortonandrew morton940.66%81.83%
naohiro ooiwanaohiro ooiwa820.58%10.23%
ulrich drepperulrich drepper710.50%10.23%
david howellsdavid howells650.46%81.83%
paul e. mckenneypaul e. mckenney570.40%51.14%
will drewrywill drewry520.37%10.23%
matt flemingmatt fleming510.36%10.23%
richard weinbergerrichard weinberger510.36%30.68%
stas sergeevstas sergeev490.35%20.46%
david woodhousedavid woodhouse440.31%10.23%
chris wrightchris wright420.30%30.68%
andi kleenandi kleen380.27%20.46%
qiaowei renqiaowei ren330.23%10.23%
dave hansendave hansen330.23%10.23%
vadim lobanovvadim lobanov330.23%10.23%
frederic weisbeckerfrederic weisbecker320.23%10.23%
masoud asgharifard sharbianimasoud asgharifard sharbiani310.22%10.23%
amanieu d'antrasamanieu d'antras280.20%20.46%
david p. quigleydavid p. quigley250.18%10.23%
vegard nossumvegard nossum250.18%10.23%
randy dunlaprandy dunlap240.17%61.37%
corey minyardcorey minyard240.17%10.23%
masami hiramatsumasami hiramatsu230.16%30.68%
dmitry safonovdmitry safonov220.16%10.23%
jesper juhljesper juhl220.16%20.46%
andrey vaginandrey vagin220.16%10.23%
dave mccrackendave mccracken180.13%10.23%
amy griffisamy griffis160.11%10.23%
helge dellerhelge deller160.11%10.23%
davide libenzidavide libenzi150.11%10.23%
nicolas pitrenicolas pitre150.11%10.23%
waiman longwaiman long140.10%10.23%
srikar dronamrajusrikar dronamraju140.10%10.23%
peter zijlstrapeter zijlstra130.09%10.23%
kees cookkees cook120.08%10.23%
sasha levinsasha levin100.07%10.23%
namhyung kimnamhyung kim90.06%20.46%
andy lutomirskiandy lutomirski90.06%20.46%
martin schwidefskymartin schwidefsky90.06%20.46%
kirill korotaevkirill korotaev80.06%10.23%
david s. millerdavid s. miller80.06%30.68%
roland dreierroland dreier80.06%10.23%
jesper derehagjesper derehag80.06%10.23%
jamie ilesjamie iles80.06%10.23%
miklos szeredimiklos szeredi70.05%10.23%
ed swierked swierk60.04%10.23%
greg kroah-hartmangreg kroah-hartman60.04%30.68%
rafael j. wysockirafael j. wysocki60.04%10.23%
matthew wilcoxmatthew wilcox60.04%10.23%
davidlohr buesodavidlohr bueso60.04%10.23%
benjamin herrenschmidtbenjamin herrenschmidt50.04%10.23%
wang xiaoqiangwang xiaoqiang50.04%10.23%
petr vandrovec*petr vandrovec*50.04%10.23%
julien tinnesjulien tinnes50.04%10.23%
jiri slabyjiri slaby40.03%10.23%
mathieu desnoyersmathieu desnoyers40.03%20.46%
gideon israel dsouzagideon israel dsouza40.03%10.23%
daniel jacobowitzdaniel jacobowitz30.02%10.23%
palmer dabbeltpalmer dabbelt30.02%10.23%
arnd bergmannarnd bergmann30.02%10.23%
pavel machekpavel machek30.02%10.23%
alex kellyalex kelly30.02%10.23%
christoph lameterchristoph lameter30.02%20.46%
nigel cunninghamnigel cunningham30.02%10.23%
dave jonesdave jones30.02%10.23%
gustavo padovangustavo padovan30.02%10.23%
pawel sikorapawel sikora20.01%10.23%
emese revfyemese revfy20.01%10.23%
bhavesh p. davdabhavesh p. davda20.01%10.23%
michael kerriskmichael kerrisk20.01%10.23%
fabian frederickfabian frederick20.01%10.23%
valdis kletnieksvaldis kletnieks20.01%10.23%
robert p. j. dayrobert p. j. day10.01%10.23%
vineet guptavineet gupta10.01%10.23%
paul gortmakerpaul gortmaker10.01%10.23%
Total14136100.00%438100.00%
Directory: kernel
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