From patchwork Wed Oct 12 14:32:16 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Pisati X-Patchwork-Id: 119218 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from chlorine.canonical.com (chlorine.canonical.com [91.189.94.204]) by ozlabs.org (Postfix) with ESMTP id C4B8BB6F62 for ; Thu, 13 Oct 2011 01:32:33 +1100 (EST) Received: from localhost ([127.0.0.1] helo=chlorine.canonical.com) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1RDzr5-0005uv-GA; Wed, 12 Oct 2011 14:32:23 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1RDzr2-0005uF-Vz for kernel-team@lists.ubuntu.com; Wed, 12 Oct 2011 14:32:21 +0000 Received: from dynamic-adsl-94-36-124-73.clienti.tiscali.it ([94.36.124.73] helo=canonical.com) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1RDzr2-0007mg-OB for kernel-team@lists.ubuntu.com; Wed, 12 Oct 2011 14:32:20 +0000 From: Paolo Pisati To: kernel-team@lists.ubuntu.com Subject: [PATCH] [hardy] NLM: Don't hang forever on NLM unlock requests - CVE-2011-2491 Date: Wed, 12 Oct 2011 16:32:16 +0200 Message-Id: <1318429938-16867-2-git-send-email-paolo.pisati@canonical.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1318429938-16867-1-git-send-email-paolo.pisati@canonical.com> References: <1318429938-16867-1-git-send-email-paolo.pisati@canonical.com> X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.13 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: kernel-team-bounces@lists.ubuntu.com Errors-To: kernel-team-bounces@lists.ubuntu.com From: Trond Myklebust NLM: Don't hang forever on NLM unlock requests If the NLM daemon is killed on the NFS server, we can currently end up hanging forever on an 'unlock' request, instead of aborting. Basically, if the rpcbind request fails, or the server keeps returning garbage, we really want to quit instead of retrying. Tested-by: Vasily Averin Signed-off-by: Trond Myklebust Cc: stable@kernel.org CVE-2011-2491 BugLink: http://bugs.launchpad.net/bugs/869237 commit upstream 0b760113a3a155269a3fba93a409c640031dd68f Signed-off-by: Paolo Pisati --- fs/lockd/clntproc.c | 8 +++++++- include/linux/sunrpc/sched.h | 1 + net/sunrpc/clnt.c | 3 +++ net/sunrpc/sched.c | 1 + 4 files changed, 12 insertions(+), 1 deletions(-) diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c index a10343b..e288810 100644 --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -655,7 +655,13 @@ static void nlmclnt_unlock_callback(struct rpc_task *task, void *data) if (task->tk_status < 0) { dprintk("lockd: unlock failed (err = %d)\n", -task->tk_status); - goto retry_rebind; + switch (task->tk_status) { + case -EACCES: + case -EIO: + goto die; + default: + goto retry_rebind; + } } if (status == NLM_LCK_DENIED_GRACE_PERIOD) { rpc_delay(task, NLMCLNT_GRACE_WAIT); diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h index 8ea077d..1ab5a60 100644 --- a/include/linux/sunrpc/sched.h +++ b/include/linux/sunrpc/sched.h @@ -55,6 +55,7 @@ struct rpc_task { struct rpc_message tk_msg; /* RPC call info */ __u8 tk_garb_retry; __u8 tk_cred_retry; + __u8 tk_rebind_retry; unsigned long tk_cookie; /* Cookie for batching tasks */ diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 76be83e..31b5956 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -964,6 +964,9 @@ call_bind_status(struct rpc_task *task) status = -EOPNOTSUPP; break; } + if (task->tk_rebind_retry == 0) + break; + task->tk_rebind_retry--; rpc_delay(task, 3*HZ); goto retry_timeout; case -ETIMEDOUT: diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c index c98873f..9e243a6 100644 --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -826,6 +826,7 @@ void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, cons /* Initialize retry counters */ task->tk_garb_retry = 2; task->tk_cred_retry = 2; + task->tk_rebind_retry = 2; task->tk_priority = RPC_PRIORITY_NORMAL; task->tk_cookie = (unsigned long)current;