}
}
-int fastcall __fatal_signal_pending(struct task_struct *tsk)
+int __fatal_signal_pending(struct task_struct *tsk)
{
return sigismember(&tsk->pending.signal, SIGKILL);
}
}
/*
- * kill_pgrp_info() sends a signal to a process group: this is what the tty
+ * __kill_pgrp_info() sends a signal to a process group: this is what the tty
* control characters do (^C, ^Z etc)
*/
return success ? 0 : retval;
}
-int kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp)
-{
- int retval;
-
- read_lock(&tasklist_lock);
- retval = __kill_pgrp_info(sig, info, pgrp);
- read_unlock(&tasklist_lock);
-
- return retval;
-}
-
int kill_pid_info(int sig, struct siginfo *info, struct pid *pid)
{
- int error;
+ int error = -ESRCH;
struct task_struct *p;
rcu_read_lock();
if (unlikely(sig_needs_tasklist(sig)))
read_lock(&tasklist_lock);
+retry:
p = pid_task(pid, PIDTYPE_PID);
- error = -ESRCH;
- if (p)
+ if (p) {
error = group_send_sig_info(sig, info, p);
+ if (unlikely(error == -ESRCH))
+ /*
+ * The task was unhashed in between, try again.
+ * If it is dead, pid_task() will return NULL,
+ * if we race with de_thread() it will find the
+ * new leader.
+ */
+ goto retry;
+ }
if (unlikely(sig_needs_tasklist(sig)))
read_unlock(&tasklist_lock);
static int kill_something_info(int sig, struct siginfo *info, int pid)
{
int ret;
- rcu_read_lock();
- if (!pid) {
- ret = kill_pgrp_info(sig, info, task_pgrp(current));
- } else if (pid == -1) {
+
+ 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;
- read_lock(&tasklist_lock);
for_each_process(p) {
if (p->pid > 1 && !same_thread_group(p, current)) {
int err = group_send_sig_info(sig, info, p);
retval = err;
}
}
- read_unlock(&tasklist_lock);
ret = count ? retval : -ESRCH;
- } else if (pid < 0) {
- ret = kill_pgrp_info(sig, info, find_vpid(-pid));
- } else {
- ret = kill_pid_info(sig, info, find_vpid(pid));
}
- rcu_read_unlock();
+ read_unlock(&tasklist_lock);
+
return ret;
}
return send_sig_info(sig, __si_special(priv), p);
}
-/*
- * This is the entry point for "process-wide" signals.
- * They will go to an appropriate thread in the thread group.
- */
-int
-send_group_sig_info(int sig, struct siginfo *info, struct task_struct *p)
-{
- int ret;
- read_lock(&tasklist_lock);
- ret = group_send_sig_info(sig, info, p);
- read_unlock(&tasklist_lock);
- return ret;
-}
-
void
force_sig(int sig, struct task_struct *p)
{
int kill_pgrp(struct pid *pid, int sig, int priv)
{
- return kill_pgrp_info(sig, __si_special(priv), pid);
+ int ret;
+
+ read_lock(&tasklist_lock);
+ ret = __kill_pgrp_info(sig, __si_special(priv), pid);
+ read_unlock(&tasklist_lock);
+
+ return ret;
}
EXPORT_SYMBOL(kill_pgrp);
{
if (!likely(current->ptrace & PT_PTRACED))
return 0;
-
- if (unlikely(current->parent == current->real_parent &&
- (current->ptrace & PT_ATTACHED)))
- return 0;
-
/*
* Are we in the middle of do_coredump?
* If so and our tracer is also part of the coredump stopping
* 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 leave nostop_code in current->exit_code.
+ * 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 nostop_code, siginfo_t *info)
+static void ptrace_stop(int exit_code, int clear_code, siginfo_t *info)
{
int killed = 0;
/* Let the debugger run. */
__set_current_state(TASK_TRACED);
spin_unlock_irq(¤t->sighand->siglock);
- try_to_freeze();
read_lock(&tasklist_lock);
if (!unlikely(killed) && may_ptrace_stop()) {
do_notify_parent_cldstop(current, CLD_TRAPPED);
} else {
/*
* By the time we got the lock, our tracer went away.
- * Don't stop here.
+ * Don't drop the lock yet, another tracer may come.
*/
+ __set_current_state(TASK_RUNNING);
+ if (clear_code)
+ current->exit_code = 0;
read_unlock(&tasklist_lock);
- set_current_state(TASK_RUNNING);
- current->exit_code = nostop_code;
}
+ /*
+ * While in TASK_TRACED, we were considered "frozen enough".
+ * Now that we woke up, it's crucial if we're supposed to be
+ * frozen that we freeze now before running anything substantial.
+ */
+ try_to_freeze();
+
/*
* We are back. Now reacquire the siglock before touching
* last_siginfo, so that we are sure to have synchronized with
/* Let the debugger run. */
spin_lock_irq(¤t->sighand->siglock);
- ptrace_stop(exit_code, 0, &info);
+ ptrace_stop(exit_code, 1, &info);
spin_unlock_irq(¤t->sighand->siglock);
}
* stop is always done with the siglock held,
* so this check has no races.
*/
- if (!t->exit_state &&
+ if (!(t->flags & PF_EXITING) &&
!task_is_stopped_or_traced(t)) {
stop_count++;
signal_wake_up(t, 0);
return 1;
}
+static int ptrace_signal(int signr, siginfo_t *info,
+ struct pt_regs *regs, void *cookie)
+{
+ if (!(current->ptrace & PT_PTRACED))
+ return signr;
+
+ ptrace_signal_deliver(regs, cookie);
+
+ /* Let the debugger run. */
+ ptrace_stop(signr, 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;
+ info->si_pid = task_pid_vnr(current->parent);
+ info->si_uid = current->parent->uid;
+ }
+
+ /* If the (new) signal is now blocked, requeue it. */
+ if (sigismember(¤t->blocked, signr)) {
+ specific_send_sig_info(signr, info, current);
+ signr = 0;
+ }
+
+ return signr;
+}
+
int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka,
struct pt_regs *regs, void *cookie)
{
sigset_t *mask = ¤t->blocked;
int signr = 0;
+relock:
+ /*
+ * We'll jump back here after any time we were stopped in TASK_STOPPED.
+ * While in TASK_STOPPED, we were considered "frozen enough".
+ * Now that we woke up, it's crucial if we're supposed to be
+ * frozen that we freeze now before running anything substantial.
+ */
try_to_freeze();
-relock:
spin_lock_irq(¤t->sighand->siglock);
for (;;) {
struct k_sigaction *ka;
if (!signr)
break; /* will return 0 */
- if ((current->ptrace & PT_PTRACED) && signr != SIGKILL) {
- ptrace_signal_deliver(regs, cookie);
-
- /* Let the debugger run. */
- ptrace_stop(signr, signr, info);
-
- /* We're back. Did the debugger cancel the sig? */
- signr = current->exit_code;
- if (signr == 0)
+ if (signr != SIGKILL) {
+ signr = ptrace_signal(signr, info, regs, cookie);
+ if (!signr)
continue;
-
- 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;
- info->si_pid = task_pid_vnr(current->parent);
- info->si_uid = current->parent->uid;
- }
-
- /* If the (new) signal is now blocked, requeue it. */
- if (sigismember(¤t->blocked, signr)) {
- specific_send_sig_info(signr, info, current);
- continue;
- }
}
ka = ¤t->sighand->action[signr-1];
return signr;
}
+void exit_signals(struct task_struct *tsk)
+{
+ int group_stop = 0;
+ struct task_struct *t;
+
+ if (thread_group_empty(tsk) || signal_group_exit(tsk->signal)) {
+ tsk->flags |= PF_EXITING;
+ 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;
+ if (!signal_pending(tsk))
+ goto out;
+
+ /* It could be that __group_complete_signal() choose us to
+ * notify about group-wide signal. Another thread should be
+ * woken now to take the signal since we will not.
+ */
+ for (t = tsk; (t = next_thread(t)) != tsk; )
+ if (!signal_pending(t) && !(t->flags & PF_EXITING))
+ recalc_sigpending_and_wake(t);
+
+ if (unlikely(tsk->signal->group_stop_count) &&
+ !--tsk->signal->group_stop_count) {
+ tsk->signal->flags = SIGNAL_STOP_STOPPED;
+ group_stop = 1;
+ }
+out:
+ spin_unlock_irq(&tsk->sighand->siglock);
+
+ if (unlikely(group_stop)) {
+ read_lock(&tasklist_lock);
+ do_notify_parent_cldstop(tsk, CLD_STOPPED);
+ read_unlock(&tasklist_lock);
+ }
+}
+
EXPORT_SYMBOL(recalc_sigpending);
EXPORT_SYMBOL_GPL(dequeue_signal);
EXPORT_SYMBOL(flush_signals);