From 78d2978874e4e10e97dfd4fd79db45bdc0748550 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Fri, 4 Feb 2011 18:13:24 +0000 Subject: [PATCH] CRED: Fix kernel panic upon security_file_alloc() failure. In get_empty_filp() since 2.6.29, file_free(f) is called with f->f_cred == NULL when security_file_alloc() returned an error. As a result, kernel will panic() due to put_cred(NULL) call within RCU callback. Fix this bug by assigning f->f_cred before calling security_file_alloc(). Signed-off-by: Tetsuo Handa Signed-off-by: David Howells Signed-off-by: Linus Torvalds --- fs/file_table.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/file_table.c b/fs/file_table.c index c3e89adf53c0..eb36b6b17e26 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -125,13 +125,13 @@ struct file *get_empty_filp(void) goto fail; percpu_counter_inc(&nr_files); + f->f_cred = get_cred(cred); if (security_file_alloc(f)) goto fail_sec; INIT_LIST_HEAD(&f->f_u.fu_list); atomic_long_set(&f->f_count, 1); rwlock_init(&f->f_owner.lock); - f->f_cred = get_cred(cred); spin_lock_init(&f->f_lock); eventpoll_init_file(f); /* f->f_version: 0 */ -- 2.20.1