Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755893Ab3DVOmc (ORCPT ); Mon, 22 Apr 2013 10:42:32 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:51538 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754847Ab3DVOaC (ORCPT ); Mon, 22 Apr 2013 10:30:02 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Linus Torvalds" , "David S. Miller" , "Eric W. Biederman" , "Andy Lutomirski" , "Serge E. Hallyn" Date: Mon, 22 Apr 2013 15:25:59 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [52/75] net: fix incorrect credentials passing In-Reply-To: X-SA-Exim-Connect-IP: 2001:470:1f08:1539:6834:ff73:7553:7f84 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3011 Lines: 83 3.2.44-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Linus Torvalds commit 83f1b4ba917db5dc5a061a44b3403ddb6e783494 upstream. Commit 257b5358b32f ("scm: Capture the full credentials of the scm sender") changed the credentials passing code to pass in the effective uid/gid instead of the real uid/gid. Obviously this doesn't matter most of the time (since normally they are the same), but it results in differences for suid binaries when the wrong uid/gid ends up being used. This just undoes that (presumably unintentional) part of the commit. Reported-by: Andy Lutomirski Cc: Eric W. Biederman Cc: Serge E. Hallyn Cc: David S. Miller Signed-off-by: Linus Torvalds Acked-by: "Eric W. Biederman" Signed-off-by: David S. Miller [bwh: Backported to 3.2: scm_set_cred() does user namespace conversion of euid/egid using cred_to_ucred(). Add and use cred_real_to_ucred() to do the same thing for real uid/gid.] Signed-off-by: Ben Hutchings --- include/net/scm.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/include/net/scm.h +++ b/include/net/scm.h @@ -50,7 +50,7 @@ static __inline__ void scm_set_cred(stru { scm->pid = get_pid(pid); scm->cred = cred ? get_cred(cred) : NULL; - cred_to_ucred(pid, cred, &scm->creds); + cred_real_to_ucred(pid, cred, &scm->creds); } static __inline__ void scm_destroy_cred(struct scm_cookie *scm) --- a/net/core/sock.c +++ b/net/core/sock.c @@ -761,6 +761,20 @@ void cred_to_ucred(struct pid *pid, cons } EXPORT_SYMBOL_GPL(cred_to_ucred); +void cred_real_to_ucred(struct pid *pid, const struct cred *cred, + struct ucred *ucred) +{ + ucred->pid = pid_vnr(pid); + ucred->uid = ucred->gid = -1; + if (cred) { + struct user_namespace *current_ns = current_user_ns(); + + ucred->uid = user_ns_map_uid(current_ns, cred, cred->uid); + ucred->gid = user_ns_map_gid(current_ns, cred, cred->gid); + } +} +EXPORT_SYMBOL_GPL(cred_real_to_ucred); + int sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen) { --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -317,6 +317,7 @@ struct ucred { #define IPX_TYPE 1 extern void cred_to_ucred(struct pid *pid, const struct cred *cred, struct ucred *ucred); +extern void cred_real_to_ucred(struct pid *pid, const struct cred *cred, struct ucred *ucred); extern int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len); extern int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/