From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anders Widell , Parthasarathy Bhuvaragan , Jon Maloy , "David S. Miller" , Sasha Levin Subject: [PATCH 4.4 082/192] [PATCH 086/135] tipc: fix nullptr crash during subscription cancel Date: Mon, 12 Sep 2016 18:59:51 +0200 Message-Id: <20160912152202.379316669@linuxfoundation.org> In-Reply-To: <20160912152158.855601725@linuxfoundation.org> References: <20160912152158.855601725@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 4de13d7ed6ffdcbb34317acaa9236f121176f5f8 ] commit 4d5cfcba2f6e ('tipc: fix connection abort during subscription cancel'), removes the check for a valid subscription before calling tipc_nametbl_subscribe(). This will lead to a nullptr exception when we process a subscription cancel request. For a cancel request, a null subscription is passed to tipc_nametbl_subscribe() resulting in exception. In this commit, we call tipc_nametbl_subscribe() only for a valid subscription. Fixes: 4d5cfcba2f6e ('tipc: fix connection abort during subscription cancel') Reported-by: Anders Widell Signed-off-by: Parthasarathy Bhuvaragan Acked-by: Jon Maloy Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/tipc/subscr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/tipc/subscr.c +++ b/net/tipc/subscr.c @@ -296,7 +296,8 @@ static void tipc_subscrb_rcv_cb(struct n if (tipc_subscrp_create(net, (struct tipc_subscr *)buf, subscrb, &sub)) return tipc_conn_terminate(tn->topsrv, subscrb->conid); - tipc_nametbl_subscribe(sub); + if (sub) + tipc_nametbl_subscribe(sub); } /* Handle one request to establish a new subscriber */