From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756679AbcH3Plt (ORCPT ); Tue, 30 Aug 2016 11:41:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51220 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756485AbcH3Plq (ORCPT ); Tue, 30 Aug 2016 11:41:46 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH net-next 1/8] rxrpc: Fix a potential NULL-pointer deref in rxrpc_abort_calls From: David Howells To: netdev@vger.kernel.org Cc: dhowells@redhat.com, linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org Date: Tue, 30 Aug 2016 16:41:44 +0100 Message-ID: <147257170401.6391.16219091111450190401.stgit@warthog.procyon.org.uk> In-Reply-To: <147257169706.6391.3116382288289485794.stgit@warthog.procyon.org.uk> References: <147257169706.6391.3116382288289485794.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 30 Aug 2016 15:41:45 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The call pointer in a channel on a connection will be NULL if there's no active call on that channel. rxrpc_abort_calls() needs to check for this before trying to take the call's state_lock. Signed-off-by: David Howells --- net/rxrpc/conn_event.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c index 6296374df840..bb81801fb805 100644 --- a/net/rxrpc/conn_event.c +++ b/net/rxrpc/conn_event.c @@ -149,19 +149,23 @@ static void rxrpc_abort_calls(struct rxrpc_connection *conn, int state, call = rcu_dereference_protected( conn->channels[i].call, lockdep_is_held(&conn->channel_lock)); - write_lock_bh(&call->state_lock); - if (call->state <= RXRPC_CALL_COMPLETE) { - call->state = state; - if (state == RXRPC_CALL_LOCALLY_ABORTED) { - call->local_abort = conn->local_abort; - set_bit(RXRPC_CALL_EV_CONN_ABORT, &call->events); - } else { - call->remote_abort = conn->remote_abort; - set_bit(RXRPC_CALL_EV_RCVD_ABORT, &call->events); + if (call) { + write_lock_bh(&call->state_lock); + if (call->state <= RXRPC_CALL_COMPLETE) { + call->state = state; + if (state == RXRPC_CALL_LOCALLY_ABORTED) { + call->local_abort = conn->local_abort; + set_bit(RXRPC_CALL_EV_CONN_ABORT, + &call->events); + } else { + call->remote_abort = conn->remote_abort; + set_bit(RXRPC_CALL_EV_RCVD_ABORT, + &call->events); + } + rxrpc_queue_call(call); } - rxrpc_queue_call(call); + write_unlock_bh(&call->state_lock); } - write_unlock_bh(&call->state_lock); } spin_unlock(&conn->channel_lock);