Fix ptrace self-attach rule
Before we did CLONE_THREAD, the way to check whether we were attaching
to ourselves was to just check "current == task", but with CLONE_THREAD
we should check that the thread group ID matches instead.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 5b8dd98..b88d418 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -155,7 +155,7 @@
retval = -EPERM;
if (task->pid <= 1)
goto bad;
- if (task == current)
+ if (task->tgid == current->tgid)
goto bad;
/* the same process cannot be attached many times */
if (task->ptrace & PT_PTRACED)