I blindly copied this code from ptrace_resume() but it is wrong.
task_is_stopped() can never be true, and we must not use ->sighand
directly. Since the tracee should be TRACED or killed we do not
check tracee->state at all.
Fixes a couple of tests...
---
kernel/ptrace.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
--- PU/kernel/ptrace.c~29_WAKEUP_COMPAT_BUG 2009-09-12 00:13:34.000000000
+0200
+++ PU/kernel/ptrace.c 2009-09-12 00:59:10.000000000 +0200
@@ -320,12 +320,13 @@ static void ptrace_wake_up(struct utrace
struct task_struct *tracee,
enum utrace_resume_action action)
{
+ unsigned long flags;
+
/* preserve the compatibility bug */
- if (task_is_stopped(tracee)) {
- spin_lock_irq(&tracee->sighand->siglock);
- tracee->signal->flags &= ~SIGNAL_STOP_STOPPED;
- spin_unlock_irq(&tracee->sighand->siglock);
- }
+ if (!lock_task_sighand(tracee, &flags))
+ return;
+ tracee->signal->flags &= ~SIGNAL_STOP_STOPPED;
+ unlock_task_sighand(tracee, &flags);
// XXX: FIXME!!! racy.
tracee->exit_code = 0;
@@ -1134,10 +1135,11 @@ static int ptrace_resume(struct task_str
do_notify_parent_cldstop(child, CLD_TRAPPED);
read_unlock(&tasklist_lock);
} else {
- if (task_is_stopped(child)) {
- spin_lock_irq(&child->sighand->siglock);
+ unsigned long flags;
+
+ if (lock_task_sighand(child, &flags)) {
child->signal->flags &= ~SIGNAL_STOP_STOPPED;
- spin_unlock_irq(&child->sighand->siglock);
+ unlock_task_sighand(child, &flags);
}
/*
