Commit 04ec93fe authored by Li Zefan's avatar Li Zefan Committed by Linus Torvalds

fork.c: fix NULL pointer dereference when nr_threads == threads-max

I happened to forked lots of processes, and hit NULL pointer dereference.
It is because in copy_process() after checking max_threads, 0 is returned
but not -EAGAIN.

The bug is introduced by "CRED: Detach the credentials from task_struct"
(commit f1752eec).
Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Acked-by: default avatarJames Morris <jmorris@namei.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b2a740aa
...@@ -1005,6 +1005,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, ...@@ -1005,6 +1005,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
* triggers too late. This doesn't hurt, the check is only there * triggers too late. This doesn't hurt, the check is only there
* to stop root fork bombs. * to stop root fork bombs.
*/ */
retval = -EAGAIN;
if (nr_threads >= max_threads) if (nr_threads >= max_threads)
goto bad_fork_cleanup_count; goto bad_fork_cleanup_count;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment