From: Serge E. Hallyn <serge@hallyn.com>
Date: Thu, 26 May 2011 20:25:05 +0000 (-0500)
Subject: Set cred->user_ns in key_replace_session_keyring
X-Git-Tag: v2.6.39.1~31
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=82ce79999abf4899b10481209db7f0af8057a561;p=karo-tx-linux.git

Set cred->user_ns in key_replace_session_keyring

commit f7285b5d631fd6096b11c6af0058ed3a2b30ef4e upstream.

Since this cred was not created with copy_creds(), it needs to get
initialized.  Otherwise use of syscall(__NR_keyctl, KEYCTL_SESSION_TO_PARENT);
can lead to a NULL deref.  Thanks to Robert for finding this.

But introduced by commit 47a150edc2a ("Cache user_ns in struct cred").

Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Reported-by: Robert Święcki <robert@swiecki.net>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 930634e45149..7a0c5868651f 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -845,6 +845,7 @@ void key_replace_session_keyring(void)
 	new-> sgid	= old-> sgid;
 	new->fsgid	= old->fsgid;
 	new->user	= get_uid(old->user);
+	new->user_ns	= new->user->user_ns;
 	new->group_info	= get_group_info(old->group_info);
 
 	new->securebits	= old->securebits;