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 X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3CB8CC28B25 for ; Mon, 6 Sep 2021 01:36:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32BAE60F3A for ; Mon, 6 Sep 2021 01:36:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241548AbhIFBgR (ORCPT ); Sun, 5 Sep 2021 21:36:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:48338 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351931AbhIFBbQ (ORCPT ); Sun, 5 Sep 2021 21:31:16 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C5C0661050; Mon, 6 Sep 2021 01:24:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1630891487; bh=ygTgi3ZOuywsl37Y3rfKuIb8lCI6FVLBpXonPSgzYwY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ocbcrS5JdIHOsZQLi1FCta2nLVTNOeWzkjN2DCRI2axtbCghMvyOA1G4wGCg4GDsV f7atlsP+IWSZOIbSu7YtMkIh+oxp1TNIu5j/7IaWHdnb21JEx1j6V1MU3raUSK5w9q AMqIBeF93ycf9M+Be35VYNKiUhuj4lXFOdUik+5RO314jkeErEo/NVOC3j8VX1OU4l ZmhtYJu3CNTjJHLyJWKWfhlRyAjQ0aNspShuo3R8S0rn88SJU2ZOPVEm/52RfQK0qc KrMS9Zdi8dyW3+cOnDijL5qnekxhhRaGpHtLG9x4qJHT2SXcAa+WCOMpTLMv0PJfW4 mQoVotJOOZ10g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Stian Skjelstad , Jan Kara , Sasha Levin Subject: [PATCH AUTOSEL 4.4 9/9] udf_get_extendedattr() had no boundary checks. Date: Sun, 5 Sep 2021 21:24:34 -0400 Message-Id: <20210906012435.931318-9-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210906012435.931318-1-sashal@kernel.org> References: <20210906012435.931318-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Stian Skjelstad [ Upstream commit 58bc6d1be2f3b0ceecb6027dfa17513ec6aa2abb ] When parsing the ExtendedAttr data, malicous or corrupt attribute length could cause kernel hangs and buffer overruns in some special cases. Link: https://lore.kernel.org/r/20210822093332.25234-1-stian.skjelstad@gmail.com Signed-off-by: Stian Skjelstad Signed-off-by: Jan Kara Signed-off-by: Sasha Levin --- fs/udf/misc.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/fs/udf/misc.c b/fs/udf/misc.c index 71d1c25f360d..8c7f9ea251e5 100644 --- a/fs/udf/misc.c +++ b/fs/udf/misc.c @@ -175,13 +175,22 @@ struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type, else offset = le32_to_cpu(eahd->appAttrLocation); - while (offset < iinfo->i_lenEAttr) { + while (offset + sizeof(*gaf) < iinfo->i_lenEAttr) { + uint32_t attrLength; + gaf = (struct genericFormat *)&ea[offset]; + attrLength = le32_to_cpu(gaf->attrLength); + + /* Detect undersized elements and buffer overflows */ + if ((attrLength < sizeof(*gaf)) || + (attrLength > (iinfo->i_lenEAttr - offset))) + break; + if (le32_to_cpu(gaf->attrType) == type && gaf->attrSubtype == subtype) return gaf; else - offset += le32_to_cpu(gaf->attrLength); + offset += attrLength; } } -- 2.30.2