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-rw-r--r--kernel/signal.c425
1 files changed, 267 insertions, 158 deletions
diff --git a/kernel/signal.c b/kernel/signal.c
index 415d85d6f6c6..d7f70aed1cc0 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -87,7 +87,7 @@ static int sig_ignored(struct task_struct *t, int sig, int from_ancestor_ns)
/*
* Tracers may want to know about even ignored signals.
*/
- return !tracehook_consider_ignored_signal(t, sig);
+ return !t->ptrace;
}
/*
@@ -124,7 +124,7 @@ static inline int has_pending_signals(sigset_t *signal, sigset_t *blocked)
static int recalc_sigpending_tsk(struct task_struct *t)
{
- if ((t->group_stop & GROUP_STOP_PENDING) ||
+ 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);
@@ -150,9 +150,7 @@ void recalc_sigpending_and_wake(struct task_struct *t)
void recalc_sigpending(void)
{
- if (unlikely(tracehook_force_sigpending()))
- set_thread_flag(TIF_SIGPENDING);
- else if (!recalc_sigpending_tsk(current) && !freezing(current))
+ if (!recalc_sigpending_tsk(current) && !freezing(current))
clear_thread_flag(TIF_SIGPENDING);
}
@@ -224,47 +222,93 @@ static inline void print_dropped_signal(int sig)
}
/**
- * task_clear_group_stop_trapping - clear group stop trapping bit
+ * task_set_jobctl_pending - set jobctl pending bits
* @task: target task
+ * @mask: pending bits to set
*
- * If GROUP_STOP_TRAPPING is set, a ptracer is waiting for us. 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.
+ * Clear @mask from @task->jobctl. @mask must be subset of
+ * %JOBCTL_PENDING_MASK | %JOBCTL_STOP_CONSUME | %JOBCTL_STOP_SIGMASK |
+ * %JOBCTL_TRAPPING. If stop signo is being set, the existing signo is
+ * cleared. If @task is already being killed or exiting, this function
+ * becomes noop.
+ *
+ * CONTEXT:
+ * Must be called with @task->sighand->siglock held.
+ *
+ * RETURNS:
+ * %true if @mask is set, %false if made noop because @task was dying.
+ */
+bool task_set_jobctl_pending(struct task_struct *task, unsigned int mask)
+{
+ BUG_ON(mask & ~(JOBCTL_PENDING_MASK | JOBCTL_STOP_CONSUME |
+ JOBCTL_STOP_SIGMASK | JOBCTL_TRAPPING));
+ BUG_ON((mask & JOBCTL_TRAPPING) && !(mask & JOBCTL_PENDING_MASK));
+
+ if (unlikely(fatal_signal_pending(task) || (task->flags & PF_EXITING)))
+ return false;
+
+ if (mask & JOBCTL_STOP_SIGMASK)
+ task->jobctl &= ~JOBCTL_STOP_SIGMASK;
+
+ task->jobctl |= mask;
+ return true;
+}
+
+/**
+ * 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.
*/
-static void task_clear_group_stop_trapping(struct task_struct *task)
+void task_clear_jobctl_trapping(struct task_struct *task)
{
- if (unlikely(task->group_stop & GROUP_STOP_TRAPPING)) {
- task->group_stop &= ~GROUP_STOP_TRAPPING;
- __wake_up_sync_key(&task->parent->signal->wait_chldexit,
- TASK_UNINTERRUPTIBLE, 1, task);
+ if (unlikely(task->jobctl & JOBCTL_TRAPPING)) {
+ task->jobctl &= ~JOBCTL_TRAPPING;
+ wake_up_bit(&task->jobctl, JOBCTL_TRAPPING_BIT);
}
}
/**
- * task_clear_group_stop_pending - clear pending group stop
+ * 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.
*
- * Clear group stop states for @task.
+ * 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_group_stop_pending(struct task_struct *task)
+void task_clear_jobctl_pending(struct task_struct *task, unsigned int mask)
{
- task->group_stop &= ~(GROUP_STOP_PENDING | GROUP_STOP_CONSUME |
- GROUP_STOP_DEQUEUED);
+ 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);
}
/**
* task_participate_group_stop - participate in a group stop
* @task: task participating in a group stop
*
- * @task has GROUP_STOP_PENDING set and is 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
- * %GROUP_STOP_CONSUME was set. If the consumption completes the group
+ * %JOBCTL_STOP_CONSUME was set. If the consumption completes the group
* stop, the appropriate %SIGNAL_* flags are set.
*
* CONTEXT:
@@ -277,11 +321,11 @@ void task_clear_group_stop_pending(struct task_struct *task)
static bool task_participate_group_stop(struct task_struct *task)
{
struct signal_struct *sig = task->signal;
- bool consume = task->group_stop & GROUP_STOP_CONSUME;
+ bool consume = task->jobctl & JOBCTL_STOP_CONSUME;
- WARN_ON_ONCE(!(task->group_stop & GROUP_STOP_PENDING));
+ WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING));
- task_clear_group_stop_pending(task);
+ task_clear_jobctl_pending(task, JOBCTL_STOP_PENDING);
if (!consume)
return false;
@@ -449,7 +493,8 @@ int unhandled_signal(struct task_struct *tsk, int sig)
return 1;
if (handler != SIG_IGN && handler != SIG_DFL)
return 0;
- return !tracehook_consider_fatal_signal(tsk, sig);
+ /* if ptraced, let the tracer determine */
+ return !tsk->ptrace;
}
/*
@@ -604,7 +649,7 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
* is to alert stop-signal processing code when another
* processor has come along and cleared the flag.
*/
- current->group_stop |= GROUP_STOP_DEQUEUED;
+ current->jobctl |= JOBCTL_STOP_DEQUEUED;
}
if ((info->si_code & __SI_MASK) == __SI_TIMER && info->si_sys_private) {
/*
@@ -773,6 +818,32 @@ static int check_kill_permission(int sig, struct siginfo *info,
return security_task_kill(t, info, sig, 0);
}
+/**
+ * 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);
+ signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
+}
+
/*
* Handle magic process-wide effects of stop/continue signals. Unlike
* the signal actions, these happen immediately at signal-generation
@@ -809,9 +880,12 @@ static int prepare_signal(int sig, struct task_struct *p, int from_ancestor_ns)
rm_from_queue(SIG_KERNEL_STOP_MASK, &signal->shared_pending);
t = p;
do {
- task_clear_group_stop_pending(t);
+ task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING);
rm_from_queue(SIG_KERNEL_STOP_MASK, &t->pending);
- wake_up_state(t, __TASK_STOPPED);
+ if (likely(!(t->ptrace & PT_SEIZED)))
+ wake_up_state(t, __TASK_STOPPED);
+ else
+ ptrace_trap_notify(t);
} while_each_thread(p, t);
/*
@@ -908,8 +982,7 @@ static void complete_signal(int sig, struct task_struct *p, int group)
if (sig_fatal(p, sig) &&
!(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) &&
!sigismember(&t->real_blocked, sig) &&
- (sig == SIGKILL ||
- !tracehook_consider_fatal_signal(t, sig))) {
+ (sig == SIGKILL || !t->ptrace)) {
/*
* This signal will be fatal to the whole group.
*/
@@ -925,7 +998,7 @@ static void complete_signal(int sig, struct task_struct *p, int group)
signal->group_stop_count = 0;
t = p;
do {
- task_clear_group_stop_pending(t);
+ task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK);
sigaddset(&t->pending.signal, SIGKILL);
signal_wake_up(t, 1);
} while_each_thread(p, t);
@@ -1160,7 +1233,7 @@ int zap_other_threads(struct task_struct *p)
p->signal->group_stop_count = 0;
while_each_thread(p, t) {
- task_clear_group_stop_pending(t);
+ task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK);
count++;
/* Don't bother with already dead threads */
@@ -1511,22 +1584,22 @@ ret:
* Let a parent know about the death of a child.
* For a stopped/continued status change, use do_notify_parent_cldstop instead.
*
- * Returns -1 if our parent ignored us and so we've switched to
- * self-reaping, or else @sig.
+ * Returns true if our parent ignored us and so we've switched to
+ * self-reaping.
*/
-int do_notify_parent(struct task_struct *tsk, int sig)
+bool do_notify_parent(struct task_struct *tsk, int sig)
{
struct siginfo info;
unsigned long flags;
struct sighand_struct *psig;
- int ret = sig;
+ bool autoreap = false;
BUG_ON(sig == -1);
/* do_notify_parent_cldstop should have been called instead. */
BUG_ON(task_is_stopped_or_traced(tsk));
- BUG_ON(!task_ptrace(tsk) &&
+ BUG_ON(!tsk->ptrace &&
(tsk->group_leader != tsk || !thread_group_empty(tsk)));
info.si_signo = sig;
@@ -1565,7 +1638,7 @@ int do_notify_parent(struct task_struct *tsk, int sig)
psig = tsk->parent->sighand;
spin_lock_irqsave(&psig->siglock, flags);
- if (!task_ptrace(tsk) && sig == SIGCHLD &&
+ if (!tsk->ptrace && sig == SIGCHLD &&
(psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN ||
(psig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT))) {
/*
@@ -1583,16 +1656,16 @@ int do_notify_parent(struct task_struct *tsk, int sig)
* is implementation-defined: we do (if you don't want
* it, just use SIG_IGN instead).
*/
- ret = tsk->exit_signal = -1;
+ autoreap = true;
if (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN)
- sig = -1;
+ sig = 0;
}
- if (valid_signal(sig) && 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 ret;
+ return autoreap;
}
/**
@@ -1665,7 +1738,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk,
static inline int may_ptrace_stop(void)
{
- if (!likely(task_ptrace(current)))
+ if (!likely(current->ptrace))
return 0;
/*
* Are we in the middle of do_coredump?
@@ -1694,15 +1767,6 @@ static int sigkill_pending(struct task_struct *tsk)
}
/*
- * Test whether the target task of the usual cldstop notification - the
- * real_parent of @child - is in the same group as the ptracer.
- */
-static bool real_parent_is_ptracer(struct task_struct *child)
-{
- return same_thread_group(child->parent, child->real_parent);
-}
-
-/*
* This must be called with current->sighand->siglock held.
*
* This should be the path for all ptrace stops.
@@ -1739,31 +1803,34 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
}
/*
- * If @why is CLD_STOPPED, we're trapping to participate in a group
- * stop. Do the bookkeeping. Note that if SIGCONT was delievered
- * while siglock was released for the arch hook, PENDING could be
- * clear now. We act as if SIGCONT is received after TASK_TRACED
- * is entered - ignore it.
+ * 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.
*/
- if (why == CLD_STOPPED && (current->group_stop & GROUP_STOP_PENDING))
- gstop_done = task_participate_group_stop(current);
+ set_current_state(TASK_TRACED);
current->last_siginfo = info;
current->exit_code = exit_code;
/*
- * TRACED should be visible before TRAPPING is cleared; otherwise,
- * the tracer might fail do_wait().
+ * 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.
*/
- set_current_state(TASK_TRACED);
+ if (why == CLD_STOPPED && (current->jobctl & JOBCTL_STOP_PENDING))
+ gstop_done = task_participate_group_stop(current);
- /*
- * We're committing to trapping. Clearing GROUP_STOP_TRAPPING and
- * transition to TASK_TRACED should be atomic with respect to
- * siglock. This hsould be done after the arch hook as siglock is
- * released and regrabbed across it.
- */
- task_clear_group_stop_trapping(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);
@@ -1779,7 +1846,7 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
* separately unless they're gonna be duplicates.
*/
do_notify_parent_cldstop(current, true, why);
- if (gstop_done && !real_parent_is_ptracer(current))
+ if (gstop_done && ptrace_reparented(current))
do_notify_parent_cldstop(current, false, why);
/*
@@ -1799,9 +1866,9 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
*
* If @gstop_done, the ptracer went away between group stop
* completion and here. During detach, it would have set
- * GROUP_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.
+ * 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);
@@ -1827,6 +1894,9 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
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.
@@ -1835,44 +1905,66 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
recalc_sigpending_tsk(current);
}
-void ptrace_notify(int exit_code)
+static void ptrace_do_notify(int signr, int exit_code, int why)
{
siginfo_t info;
- BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP);
-
memset(&info, 0, sizeof info);
- info.si_signo = SIGTRAP;
+ info.si_signo = signr;
info.si_code = exit_code;
info.si_pid = task_pid_vnr(current);
info.si_uid = current_uid();
/* Let the debugger run. */
+ ptrace_stop(exit_code, why, 1, &info);
+}
+
+void ptrace_notify(int exit_code)
+{
+ BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP);
+
spin_lock_irq(&current->sighand->siglock);
- ptrace_stop(exit_code, CLD_TRAPPED, 1, &info);
+ ptrace_do_notify(SIGTRAP, exit_code, CLD_TRAPPED);
spin_unlock_irq(&current->sighand->siglock);
}
-/*
- * This performs the stopping for SIGSTOP and other stop signals.
- * We have to stop all threads in the thread group.
- * Returns non-zero if we've actually stopped and released the siglock.
- * Returns zero if we didn't stop and still hold the siglock.
+/**
+ * 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 int do_signal_stop(int signr)
+static bool do_signal_stop(int signr)
+ __releases(&current->sighand->siglock)
{
struct signal_struct *sig = current->signal;
- if (!(current->group_stop & GROUP_STOP_PENDING)) {
- unsigned int gstop = GROUP_STOP_PENDING | GROUP_STOP_CONSUME;
+ if (!(current->jobctl & JOBCTL_STOP_PENDING)) {
+ unsigned int gstop = JOBCTL_STOP_PENDING | JOBCTL_STOP_CONSUME;
struct task_struct *t;
- /* signr will be recorded in task->group_stop for retries */
- WARN_ON_ONCE(signr & ~GROUP_STOP_SIGMASK);
+ /* signr will be recorded in task->jobctl for retries */
+ WARN_ON_ONCE(signr & ~JOBCTL_STOP_SIGMASK);
- if (!likely(current->group_stop & GROUP_STOP_DEQUEUED) ||
+ if (!likely(current->jobctl & JOBCTL_STOP_DEQUEUED) ||
unlikely(signal_group_exit(sig)))
- return 0;
+ return false;
/*
* There is no group stop already in progress. We must
* initiate one now.
@@ -1895,28 +1987,32 @@ static int do_signal_stop(int signr)
if (!(sig->flags & SIGNAL_STOP_STOPPED))
sig->group_exit_code = signr;
else
- WARN_ON_ONCE(!task_ptrace(current));
+ WARN_ON_ONCE(!current->ptrace);
+
+ sig->group_stop_count = 0;
+
+ if (task_set_jobctl_pending(current, signr | gstop))
+ sig->group_stop_count++;
- current->group_stop &= ~GROUP_STOP_SIGMASK;
- current->group_stop |= signr | gstop;
- sig->group_stop_count = 1;
for (t = next_thread(current); t != current;
t = next_thread(t)) {
- t->group_stop &= ~GROUP_STOP_SIGMASK;
/*
* Setting state to TASK_STOPPED for a group
* stop is always done with the siglock held,
* so this check has no races.
*/
- if (!(t->flags & PF_EXITING) && !task_is_stopped(t)) {
- t->group_stop |= signr | gstop;
+ if (!task_is_stopped(t) &&
+ task_set_jobctl_pending(t, signr | gstop)) {
sig->group_stop_count++;
- signal_wake_up(t, 0);
+ if (likely(!(t->ptrace & PT_SEIZED)))
+ signal_wake_up(t, 0);
+ else
+ ptrace_trap_notify(t);
}
}
}
-retry:
- if (likely(!task_ptrace(current))) {
+
+ if (likely(!current->ptrace)) {
int notify = 0;
/*
@@ -1947,43 +2043,65 @@ retry:
/* Now we don't run again until woken by SIGCONT or SIGKILL */
schedule();
-
- spin_lock_irq(&current->sighand->siglock);
+ return true;
} else {
- ptrace_stop(current->group_stop & GROUP_STOP_SIGMASK,
- CLD_STOPPED, 0, NULL);
- current->exit_code = 0;
+ /*
+ * 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;
}
+}
- /*
- * GROUP_STOP_PENDING could be set if another group stop has
- * started since being woken up or ptrace wants us to transit
- * between TASK_STOPPED and TRACED. Retry group stop.
- */
- if (current->group_stop & GROUP_STOP_PENDING) {
- WARN_ON_ONCE(!(current->group_stop & GROUP_STOP_SIGMASK));
- goto retry;
+/**
+ * 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;
}
-
- /* PTRACE_ATTACH might have raced with task killing, clear trapping */
- task_clear_group_stop_trapping(current);
-
- spin_unlock_irq(&current->sighand->siglock);
-
- tracehook_finish_jctl();
-
- return 1;
}
static int ptrace_signal(int signr, siginfo_t *info,
struct pt_regs *regs, void *cookie)
{
- if (!task_ptrace(current))
- return signr;
-
ptrace_signal_deliver(regs, cookie);
-
- /* Let the debugger run. */
+ /*
+ * 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? */
@@ -2039,7 +2157,6 @@ relock:
* the CLD_ si_code into SIGNAL_CLD_MASK bits.
*/
if (unlikely(signal->flags & SIGNAL_CLD_MASK)) {
- struct task_struct *leader;
int why;
if (signal->flags & SIGNAL_CLD_CONTINUED)
@@ -2060,13 +2177,11 @@ relock:
* a duplicate.
*/
read_lock(&tasklist_lock);
-
do_notify_parent_cldstop(current, false, why);
- leader = current->group_leader;
- if (task_ptrace(leader) && !real_parent_is_ptracer(leader))
- do_notify_parent_cldstop(leader, true, why);
-
+ if (ptrace_reparented(current->group_leader))
+ do_notify_parent_cldstop(current->group_leader,
+ true, why);
read_unlock(&tasklist_lock);
goto relock;
@@ -2074,37 +2189,31 @@ relock:
for (;;) {
struct k_sigaction *ka;
- /*
- * Tracing can induce an artificial signal and choose sigaction.
- * The return value in @signr determines the default action,
- * but @info->si_signo is the signal number we will report.
- */
- signr = tracehook_get_signal(current, regs, info, return_ka);
- if (unlikely(signr < 0))
+
+ if (unlikely(current->jobctl & JOBCTL_STOP_PENDING) &&
+ do_signal_stop(0))
goto relock;
- if (unlikely(signr != 0))
- ka = return_ka;
- else {
- if (unlikely(current->group_stop &
- GROUP_STOP_PENDING) && do_signal_stop(0))
- goto relock;
- signr = dequeue_signal(current, &current->blocked,
- info);
+ if (unlikely(current->jobctl & JOBCTL_TRAP_MASK)) {
+ do_jobctl_trap();
+ spin_unlock_irq(&sighand->siglock);
+ goto relock;
+ }
- if (!signr)
- break; /* will return 0 */
+ signr = dequeue_signal(current, &current->blocked, info);
- if (signr != SIGKILL) {
- signr = ptrace_signal(signr, info,
- regs, cookie);
- if (!signr)
- continue;
- }
+ if (!signr)
+ break; /* will return 0 */
- ka = &sighand->action[signr-1];
+ if (unlikely(current->ptrace) && signr != SIGKILL) {
+ signr = ptrace_signal(signr, info,
+ regs, cookie);
+ if (!signr)
+ continue;
}
+ ka = &sighand->action[signr-1];
+
/* Trace actually delivered signals. */
trace_signal_deliver(signr, info, ka);
@@ -2260,7 +2369,7 @@ void exit_signals(struct task_struct *tsk)
signotset(&unblocked);
retarget_shared_pending(tsk, &unblocked);
- if (unlikely(tsk->group_stop & GROUP_STOP_PENDING) &&
+ if (unlikely(tsk->jobctl & JOBCTL_STOP_PENDING) &&
task_participate_group_stop(tsk))
group_stop = CLD_STOPPED;
out:

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