From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5BF5C433EF for ; Mon, 1 Nov 2021 09:21:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91E43611C8 for ; Mon, 1 Nov 2021 09:21:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232167AbhKAJYO (ORCPT ); Mon, 1 Nov 2021 05:24:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:58242 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232276AbhKAJWi (ORCPT ); Mon, 1 Nov 2021 05:22:38 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D6B0160FC4; Mon, 1 Nov 2021 09:19:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1635758383; bh=ocp48DkTY7kLC6jIyi1Tr/DeEqvaghmAsPPVA29C9fI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V35EqT9fGRY5AjBBHK7Cpbu1EYTAo7fKo0f6fsAOlMgkXGSiOC6CrR7a8kqBqVMto +cm+Ms92JOCxRAnfCnc/Qc5ivFUvCBEYAaZyACmwp+QAPPI61GWMhdHa1DuSGRMlav XlQq1LTr/PiyY+Rs4ObojA8EkCQ8wJFi13PMA6NA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xin Long , Marcelo Ricardo Leitner , Jakub Kicinski , Sasha Levin Subject: [PATCH 4.9 20/20] sctp: add vtag check in sctp_sf_violation Date: Mon, 1 Nov 2021 10:17:29 +0100 Message-Id: <20211101082448.446922290@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211101082444.133899096@linuxfoundation.org> References: <20211101082444.133899096@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xin Long [ Upstream commit aa0f697e45286a6b5f0ceca9418acf54b9099d99 ] sctp_sf_violation() is called when processing HEARTBEAT_ACK chunk in cookie_wait state, and some other places are also using it. The vtag in the chunk's sctphdr should be verified, otherwise, as later in chunk length check, it may send abort with the existent asoc's vtag, which can be exploited by one to cook a malicious chunk to terminate a SCTP asoc. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sctp/sm_statefuns.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index c3d293dc8281..f71991520ad6 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -4333,6 +4333,9 @@ sctp_disposition_t sctp_sf_violation(struct net *net, { struct sctp_chunk *chunk = arg; + if (!sctp_vtag_verify(chunk, asoc)) + return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); + /* Make sure that the chunk has a valid length. */ if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, -- 2.33.0