From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753956AbbLIKpk (ORCPT ); Wed, 9 Dec 2015 05:45:40 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:44943 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753711AbbLIJia (ORCPT ); Wed, 9 Dec 2015 04:38:30 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Sowmini Varadhan , "David S. Miller" , Luis Henriques Subject: [PATCH 3.16.y-ckt 004/126] RDS-TCP: Recover correctly from pskb_pull()/pksb_trim() failure in rds_tcp_data_recv Date: Wed, 9 Dec 2015 09:36:14 +0000 Message-Id: <1449653896-5236-5-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1449653896-5236-1-git-send-email-luis.henriques@canonical.com> References: <1449653896-5236-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt21 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Sowmini Varadhan commit 8ce675ff39b9958d1c10f86cf58e357efaafc856 upstream. 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: Luis Henriques --- net/rds/tcp_recv.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/net/rds/tcp_recv.c b/net/rds/tcp_recv.c index 9ae6e0a264ec..2dd88db4a1a2 100644 --- a/net/rds/tcp_recv.c +++ b/net/rds/tcp_recv.c @@ -234,8 +234,15 @@ static int rds_tcp_data_recv(read_descriptor_t *desc, struct sk_buff *skb, } 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 -> "