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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, 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 2F750C433F5 for ; Mon, 20 Sep 2021 17:14:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16BEE63210 for ; Mon, 20 Sep 2021 17:14:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245478AbhITRQF (ORCPT ); Mon, 20 Sep 2021 13:16:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:42492 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344275AbhITRNq (ORCPT ); Mon, 20 Sep 2021 13:13:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id CEC71619EB; Mon, 20 Sep 2021 16:57:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1632157079; bh=dfQULT2cZ6sVpSpjD1dVGD4rSCxzCafGOvflM4ZVMDE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gmMFAUAlXhrPMMjuaqsKabKc1wHqqxQXSaqfxHOULUdd0SVOEQ+9EPXO0o0dViKoh vz5jM+vogq6b6k39r3uWXz/wAJc5N08BvU9Dvdv/zq5o/YXEcISAGrK6Om2wkKKsEO oseOnJb61C/kPRQbdafgSlReYYy/9psw59Dm4PNI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stian Skjelstad , Jan Kara , Sasha Levin Subject: [PATCH 4.14 044/217] udf_get_extendedattr() had no boundary checks. Date: Mon, 20 Sep 2021 18:41:05 +0200 Message-Id: <20210920163926.119137088@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210920163924.591371269@linuxfoundation.org> References: <20210920163924.591371269@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: 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 3949c4bec3a3..e5f4dcde309f 100644 --- a/fs/udf/misc.c +++ b/fs/udf/misc.c @@ -173,13 +173,22 @@ 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