Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752011AbdGPOG2 (ORCPT ); Sun, 16 Jul 2017 10:06:28 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43248 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751803AbdGPN6A (ORCPT ); Sun, 16 Jul 2017 09:58:00 -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, "Dmitry Vyukov" , "Steffen Klassert" , "Florian Westphal" Date: Sun, 16 Jul 2017 14:56:46 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 001/178] xfrm: policy: init locks early In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 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: 2286 Lines: 65 3.16.46-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Florian Westphal commit c282222a45cb9503cbfbebfdb60491f06ae84b49 upstream. Dmitry reports following splat: INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 0 PID: 13059 Comm: syz-executor1 Not tainted 4.10.0-rc7-next-20170207 #1 [..] spin_lock_bh include/linux/spinlock.h:304 [inline] xfrm_policy_flush+0x32/0x470 net/xfrm/xfrm_policy.c:963 xfrm_policy_fini+0xbf/0x560 net/xfrm/xfrm_policy.c:3041 xfrm_net_init+0x79f/0x9e0 net/xfrm/xfrm_policy.c:3091 ops_init+0x10a/0x530 net/core/net_namespace.c:115 setup_net+0x2ed/0x690 net/core/net_namespace.c:291 copy_net_ns+0x26c/0x530 net/core/net_namespace.c:396 create_new_namespaces+0x409/0x860 kernel/nsproxy.c:106 unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:205 SYSC_unshare kernel/fork.c:2281 [inline] Problem is that when we get error during xfrm_net_init we will call xfrm_policy_fini which will acquire xfrm_policy_lock before it was initialized. Just move it around so locks get set up first. Reported-by: Dmitry Vyukov Fixes: 283bc9f35bbbcb0e9 ("xfrm: Namespacify xfrm state/policy locks") Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert Signed-off-by: Ben Hutchings [bwh: Backported to 3.2: xfrm_policy_lock is an rwlock] --- net/xfrm/xfrm_policy.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -2878,6 +2878,11 @@ static int __net_init xfrm_net_init(stru { int rv; + /* Initialize the per-net locks here */ + spin_lock_init(&net->xfrm.xfrm_state_lock); + rwlock_init(&net->xfrm.xfrm_policy_lock); + mutex_init(&net->xfrm.xfrm_cfg_mutex); + rv = xfrm_statistics_init(net); if (rv < 0) goto out_statistics; @@ -2894,11 +2899,6 @@ static int __net_init xfrm_net_init(stru if (rv < 0) goto out; - /* Initialize the per-net locks here */ - spin_lock_init(&net->xfrm.xfrm_state_lock); - rwlock_init(&net->xfrm.xfrm_policy_lock); - mutex_init(&net->xfrm.xfrm_cfg_mutex); - return 0; out: