Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751437AbdFGXS6 (ORCPT ); Wed, 7 Jun 2017 19:18:58 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:50842 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753551AbdFGXGE (ORCPT ); Wed, 7 Jun 2017 19:06:04 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Andy Whitcroft , Linus Torvalds , Willy Tarreau Subject: [PATCH 3.10 013/250] xfrm_user: validate XFRM_MSG_NEWAE incoming ESN size harder Date: Thu, 8 Jun 2017 00:56:39 +0200 Message-Id: <1496876436-32402-14-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1496876436-32402-1-git-send-email-w@1wt.eu> References: <1496876436-32402-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1405 Lines: 37 From: Andy Whitcroft commit f843ee6dd019bcece3e74e76ad9df0155655d0df upstream. Kees Cook has pointed out that xfrm_replay_state_esn_len() is subject to wrapping issues. To ensure we are correctly ensuring that the two ESN structures are the same size compare both the overall size as reported by xfrm_replay_state_esn_len() and the internal length are the same. CVE-2017-7184 Signed-off-by: Andy Whitcroft Acked-by: Steffen Klassert Signed-off-by: Linus Torvalds Signed-off-by: Willy Tarreau --- net/xfrm/xfrm_user.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 8b55d42..91a6a29 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -390,7 +390,11 @@ static inline int xfrm_replay_verify_len(struct xfrm_replay_state_esn *replay_es up = nla_data(rp); ulen = xfrm_replay_state_esn_len(up); - if (nla_len(rp) < ulen || xfrm_replay_state_esn_len(replay_esn) != ulen) + /* Check the overall length and the internal bitmap length to avoid + * potential overflow. */ + if (nla_len(rp) < ulen || + xfrm_replay_state_esn_len(replay_esn) != ulen || + replay_esn->bmp_len != up->bmp_len) return -EINVAL; if (up->replay_window > up->bmp_len * sizeof(__u32) * 8) -- 2.8.0.rc2.1.gbe9624a