From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754209AbaHTMGL (ORCPT ); Wed, 20 Aug 2014 08:06:11 -0400 Received: from ip4-83-240-18-248.cust.nbox.cz ([83.240.18.248]:58922 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752519AbaHTLoK (ORCPT ); Wed, 20 Aug 2014 07:44:10 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Sasha Levin , "David S. Miller" , Jiri Slaby Subject: [PATCH 3.12 041/104] iovec: make sure the caller actually wants anything in memcpy_fromiovecend Date: Wed, 20 Aug 2014 13:43:04 +0200 Message-Id: X-Mailer: git-send-email 2.0.4 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sasha Levin 3.12-stable review patch. If anyone has any objections, please let me know. =============== [ Upstream commit 06ebb06d49486676272a3c030bfeef4bd969a8e6 ] Check for cases when the caller requests 0 bytes instead of running off and dereferencing potentially invalid iovecs. Signed-off-by: Sasha Levin Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby --- net/core/iovec.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/core/iovec.c b/net/core/iovec.c index dcf0bd5fbc20..8254497bda65 100644 --- a/net/core/iovec.c +++ b/net/core/iovec.c @@ -107,6 +107,10 @@ EXPORT_SYMBOL(memcpy_toiovecend); int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov, int offset, int len) { + /* No data? Done! */ + if (len == 0) + return 0; + /* Skip over the finished iovecs */ while (offset >= iov->iov_len) { offset -= iov->iov_len; -- 2.0.4