Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932487AbbKXWhU (ORCPT ); Tue, 24 Nov 2015 17:37:20 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:40298 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755449AbbKXWfl (ORCPT ); Tue, 24 Nov 2015 17:35:41 -0500 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, "Santosh Shilimkar" , "Sowmini Varadhan" , "David S. Miller" Date: Tue, 24 Nov 2015 22:33:59 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 49/52] RDS-TCP: Recover correctly from pskb_pull()/pksb_trim() failure in rds_tcp_data_recv In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.247 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: 1870 Lines: 52 3.2.74-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Sowmini Varadhan [ Upstream commit 8ce675ff39b9958d1c10f86cf58e357efaafc856 ] Either of pskb_pull() or pskb_trim() may fail under low memory conditions. If rds_tcp_data_recv() ignores such failures, the application will receive corrupted data because the skb has not been correctly carved to the RDS datagram size. Avoid this by handling pskb_pull/pskb_trim failure in the same manner as the skb_clone failure: bail out of rds_tcp_data_recv(), and retry via the deferred call to rds_send_worker() that gets set up on ENOMEM from rds_tcp_read_sock() Signed-off-by: Sowmini Varadhan Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/rds/tcp_recv.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) --- a/net/rds/tcp_recv.c +++ b/net/rds/tcp_recv.c @@ -235,8 +235,15 @@ static int rds_tcp_data_recv(read_descri } to_copy = min(tc->t_tinc_data_rem, left); - pskb_pull(clone, offset); - pskb_trim(clone, to_copy); + if (!pskb_pull(clone, offset) || + pskb_trim(clone, to_copy)) { + pr_warn("rds_tcp_data_recv: pull/trim failed " + "left %zu data_rem %zu skb_len %d\n", + left, tc->t_tinc_data_rem, skb->len); + kfree_skb(clone); + desc->error = -ENOMEM; + goto out; + } skb_queue_tail(&tinc->ti_skb_list, clone); rdsdebug("skb %p data %p len %d off %u to_copy %zu -> " -- 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/