if (why) {
/*
- * The first thread which returns from finish_stop()
+ * 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().
*/
return send_signal(sig, info, t, 0);
}
+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;
+}
+
/*
* Force a signal that the process can't ignore: if necessary
* we unblock the signal and change any SIG_IGN to SIG_DFL.
}
}
-int __fatal_signal_pending(struct task_struct *tsk)
-{
- return sigismember(&tsk->pending.signal, SIGKILL);
-}
-EXPORT_SYMBOL(__fatal_signal_pending);
-
struct sighand_struct *lock_task_sighand(struct task_struct *tsk, unsigned long *flags)
{
struct sighand_struct *sighand;
*/
int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
{
- unsigned long flags;
- int ret;
+ int ret = check_kill_permission(sig, info, p);
- ret = check_kill_permission(sig, info, p);
-
- if (!ret && sig) {
- ret = -ESRCH;
- if (lock_task_sighand(p, &flags)) {
- ret = __group_send_sig_info(sig, info, p);
- unlock_task_sighand(p, &flags);
- }
- }
+ if (!ret && sig)
+ ret = do_send_sig_info(sig, info, p, true);
return ret;
}
* These are for backward compatibility with the rest of the kernel source.
*/
-/*
- * The caller must ensure the task can't exit.
- */
int
send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
{
- int ret;
- unsigned long flags;
-
/*
* 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;
- spin_lock_irqsave(&p->sighand->siglock, flags);
- ret = specific_send_sig_info(sig, info, p);
- spin_unlock_irqrestore(&p->sighand->siglock, flags);
- return ret;
+ return do_send_sig_info(sig, info, p, false);
}
#define __si_special(priv) \
}
/*
- * Wake up any threads in the parent blocked in wait* syscalls.
- */
-static inline void __wake_up_parent(struct task_struct *p,
- struct task_struct *parent)
-{
- wake_up_interruptible_sync(&parent->signal->wait_chldexit);
-}
-
-/*
* Let a parent know about the death of a child.
* For a stopped/continued status change, use do_notify_parent_cldstop instead.
*
spin_unlock_irq(¤t->sighand->siglock);
}
-static void
-finish_stop(int stop_count)
-{
- /*
- * 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. When ptraced, every thread reports itself.
- */
- if (tracehook_notify_jctl(stop_count == 0, CLD_STOPPED)) {
- read_lock(&tasklist_lock);
- do_notify_parent_cldstop(current, CLD_STOPPED);
- read_unlock(&tasklist_lock);
- }
-
- do {
- schedule();
- } while (try_to_freeze());
- /*
- * Now we don't run again until continued.
- */
- current->exit_code = 0;
-}
-
/*
* This performs the stopping for SIGSTOP and other stop signals.
* We have to stop all threads in the thread group.
static int do_signal_stop(int signr)
{
struct signal_struct *sig = current->signal;
- int stop_count;
+ int notify;
- if (sig->group_stop_count > 0) {
- /*
- * There is a group stop in progress. We don't need to
- * start another one.
- */
- stop_count = --sig->group_stop_count;
- } else {
+ if (!sig->group_stop_count) {
struct task_struct *t;
if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED) ||
*/
sig->group_exit_code = signr;
- stop_count = 0;
+ sig->group_stop_count = 1;
for (t = next_thread(current); t != current; t = next_thread(t))
/*
* Setting state to TASK_STOPPED for a group
*/
if (!(t->flags & PF_EXITING) &&
!task_is_stopped_or_traced(t)) {
- stop_count++;
+ sig->group_stop_count++;
signal_wake_up(t, 0);
}
- sig->group_stop_count = stop_count;
}
+ /*
+ * 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. When ptraced, every thread reports itself.
+ */
+ notify = sig->group_stop_count == 1 ? CLD_STOPPED : 0;
+ notify = tracehook_notify_jctl(notify, CLD_STOPPED);
+ /*
+ * tracehook_notify_jctl() can drop and reacquire siglock, so
+ * we keep ->group_stop_count != 0 before the call. If SIGCONT
+ * or SIGKILL comes in between ->group_stop_count == 0.
+ */
+ if (sig->group_stop_count) {
+ if (!--sig->group_stop_count)
+ sig->flags = SIGNAL_STOP_STOPPED;
+ current->exit_code = sig->group_exit_code;
+ __set_current_state(TASK_STOPPED);
+ }
+ spin_unlock_irq(¤t->sighand->siglock);
- if (stop_count == 0)
- sig->flags = SIGNAL_STOP_STOPPED;
- current->exit_code = sig->group_exit_code;
- __set_current_state(TASK_STOPPED);
+ if (notify) {
+ read_lock(&tasklist_lock);
+ do_notify_parent_cldstop(current, notify);
+ read_unlock(&tasklist_lock);
+ }
+
+ /* Now we don't run again until woken by SIGCONT or SIGKILL */
+ do {
+ schedule();
+ } while (try_to_freeze());
+
+ tracehook_finish_jctl();
+ current->exit_code = 0;
- spin_unlock_irq(¤t->sighand->siglock);
- finish_stop(stop_count);
return 1;
}
int why = (signal->flags & SIGNAL_STOP_CONTINUED)
? CLD_CONTINUED : CLD_STOPPED;
signal->flags &= ~SIGNAL_CLD_MASK;
- spin_unlock_irq(&sighand->siglock);
- if (unlikely(!tracehook_notify_jctl(1, why)))
- goto relock;
+ why = tracehook_notify_jctl(why, CLD_CONTINUED);
+ spin_unlock_irq(&sighand->siglock);
- read_lock(&tasklist_lock);
- do_notify_parent_cldstop(current->group_leader, why);
- read_unlock(&tasklist_lock);
+ if (why) {
+ read_lock(&tasklist_lock);
+ do_notify_parent_cldstop(current->group_leader, why);
+ read_unlock(&tasklist_lock);
+ }
goto relock;
}
if (unlikely(tsk->signal->group_stop_count) &&
!--tsk->signal->group_stop_count) {
tsk->signal->flags = SIGNAL_STOP_STOPPED;
- group_stop = 1;
+ group_stop = tracehook_notify_jctl(CLD_STOPPED, CLD_STOPPED);
}
out:
spin_unlock_irq(&tsk->sighand->siglock);
- if (unlikely(group_stop) && tracehook_notify_jctl(1, CLD_STOPPED)) {
+ if (unlikely(group_stop)) {
read_lock(&tasklist_lock);
- do_notify_parent_cldstop(tsk, CLD_STOPPED);
+ do_notify_parent_cldstop(tsk, group_stop);
read_unlock(&tasklist_lock);
}
}
do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
{
struct task_struct *p;
- unsigned long flags;
int error = -ESRCH;
rcu_read_lock();
/*
* The null signal is a permissions and process existence
* probe. No signal is actually delivered.
- *
- * If lock_task_sighand() fails we pretend the task dies
- * after receiving the signal. The window is tiny, and the
- * signal is private anyway.
*/
- if (!error && sig && lock_task_sighand(p, &flags)) {
- error = specific_send_sig_info(sig, info, p);
- unlock_task_sighand(p, &flags);
+ 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();
int ss_flags;
error = -EFAULT;
- if (!access_ok(VERIFY_READ, uss, sizeof(*uss))
- || __get_user(ss_sp, &uss->ss_sp)
- || __get_user(ss_flags, &uss->ss_flags)
- || __get_user(ss_size, &uss->ss_size))
+ 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;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff