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=-20.4 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,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 54DC0C11F93 for ; Tue, 6 Jul 2021 11:39:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F2E06135E for ; Tue, 6 Jul 2021 11:39:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232849AbhGFLmc (ORCPT ); Tue, 6 Jul 2021 07:42:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:47602 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237772AbhGFLhU (ORCPT ); Tue, 6 Jul 2021 07:37:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1178661F5E; Tue, 6 Jul 2021 11:29:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625570984; bh=A4QdYZ8oBR9zs9/MVrYuFTTY8xRdz18tMYVC1uI/r2A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Bakm0M3DmZtYdcSCTMupvGCzgLA/La95UeKkDdc0/rt+afo+4MXjb4LsM3skUVmUD 4G88MNty8IfBPkobllxLRdmcoVnI4ad6LpovwrY+RhjEg1ZF8Scs2nKNeGkc/DH7uS gSeYDFI4yllKyMeTa8xSMTGVhpuMjGtHgnXzBz0o0YUNJivpKpE3fB2QbDFYHO28eq 3zeuSsRK7tDAwlgBXKG24TN6BOdw57F9PyKwdsFkCB+WVy/mC2N7wId0MMrvY0pwJG JCJ7ntwJDUJeRb/a0U3iSJXNTknL91JzekidYJS1EwG20zhM+jQ3j2UdBouzwR5ztY DPCZZX1Vh5D3w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Arturo Giusti , Jan Kara , Sasha Levin Subject: [PATCH AUTOSEL 4.4 10/31] udf: Fix NULL pointer dereference in udf_symlink function Date: Tue, 6 Jul 2021 07:29:10 -0400 Message-Id: <20210706112931.2066397-10-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210706112931.2066397-1-sashal@kernel.org> References: <20210706112931.2066397-1-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: stable@vger.kernel.org From: Arturo Giusti [ Upstream commit fa236c2b2d4436d9f19ee4e5d5924e90ffd7bb43 ] In function udf_symlink, epos.bh is assigned with the value returned by udf_tgetblk. The function udf_tgetblk is defined in udf/misc.c and returns the value of sb_getblk function that could be NULL. Then, epos.bh is used without any check, causing a possible NULL pointer dereference when sb_getblk fails. This fix adds a check to validate the value of epos.bh. Link: https://bugzilla.kernel.org/show_bug.cgi?id=213083 Signed-off-by: Arturo Giusti Signed-off-by: Jan Kara Signed-off-by: Sasha Levin --- fs/udf/namei.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/udf/namei.c b/fs/udf/namei.c index f34c545f4e54..074560ad190e 100644 --- a/fs/udf/namei.c +++ b/fs/udf/namei.c @@ -945,6 +945,10 @@ static int udf_symlink(struct inode *dir, struct dentry *dentry, iinfo->i_location.partitionReferenceNum, 0); epos.bh = udf_tgetblk(sb, block); + if (unlikely(!epos.bh)) { + err = -ENOMEM; + goto out_no_entry; + } lock_buffer(epos.bh); memset(epos.bh->b_data, 0x00, bsize); set_buffer_uptodate(epos.bh); -- 2.30.2