3.3-stable review patch. If anyone has any objections, please let me know.
------------------ From: Oleg Nesterov <[email protected]> commit 79549c6dfda0603dba9a70a53467ce62d9335c33 upstream. keyctl_session_to_parent(task) sets ->replacement_session_keyring, it should be processed and cleared by key_replace_session_keyring(). However, this task can fork before it notices TIF_NOTIFY_RESUME and the new child gets the bogus ->replacement_session_keyring copied by dup_task_struct(). This is obviously wrong and, if nothing else, this leads to put_cred(already_freed_cred). change copy_creds() to clear this member. If copy_process() fails before this point the wrong ->replacement_session_keyring doesn't matter, exit_creds() won't be called. Signed-off-by: Oleg Nesterov <[email protected]> Acked-by: David Howells <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- kernel/cred.c | 2 ++ 1 file changed, 2 insertions(+) --- a/kernel/cred.c +++ b/kernel/cred.c @@ -385,6 +385,8 @@ int copy_creds(struct task_struct *p, un struct cred *new; int ret; + p->replacement_session_keyring = NULL; + if ( #ifdef CONFIG_KEYS !p->cred->thread_keyring && -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
