From 4af1036df4dd4f0d59fad9d82ed456bfa2e73fa6 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov <oleg@redhat.com> Date: Wed, 10 Dec 2014 15:45:10 -0800 Subject: [PATCH] proc: task_state: read cred->group_info outside of task_lock() task_state() reads cred->group_info under task_lock() because a long ago it was task_struct->group_info and it was actually protected by task->alloc_lock. Today this task_unlock() after rcu_read_unlock() just adds the confusion, move task_unlock() up. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Aaron Tomlin <atomlin@redhat.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com>, Cc: Sterling Alexander <stalexan@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roland McGrath <roland@hack.frob.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- fs/proc/array.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/proc/array.c b/fs/proc/array.c index cd3653e4f35c6..b5810c228c104 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -201,11 +201,10 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns, "FDSize:\t%d\n" "Groups:\t", fdt ? fdt->max_fds : 0); + task_unlock(p); rcu_read_unlock(); group_info = cred->group_info; - task_unlock(p); - for (g = 0; g < group_info->ngroups; g++) seq_printf(m, "%d ", from_kgid_munged(user_ns, GROUP_AT(group_info, g))); -- GitLab