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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 BAD17C3B1A1 for ; Fri, 14 Feb 2020 16:37:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 89C5D217F4 for ; Fri, 14 Feb 2020 16:37:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581698242; bh=wdqrxYPyjy0I0lxc+ygjYYNq7crfOp6Bd9hVxhogQZU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FgvCp6Ln7jZa/J51t9fFyOEBkJtgn5n2+JP5Yi8baThKyGJZT3C1Ccf3A0YgnbEho U8lShZ1nh4TN0Hl4gMr85claYdwKGqY39bNztuF5Nrujxl+GUmqeYiFDp1fTc6FaLh RPGjkEJ1mVccUULn4o1UgoaTbh0m8FZkxsNi0WSk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727742AbgBNQhR (ORCPT ); Fri, 14 Feb 2020 11:37:17 -0500 Received: from mail.kernel.org ([198.145.29.99]:60522 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405758AbgBNQX6 (ORCPT ); Fri, 14 Feb 2020 11:23:58 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 68D9424787; Fri, 14 Feb 2020 16:23:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581697437; bh=wdqrxYPyjy0I0lxc+ygjYYNq7crfOp6Bd9hVxhogQZU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zx6olH03uxUb2VpWuUPa1+aPNKD+fLB7ndU9WnDrn7KJ7tV2oz5+MMNUqo8pI/Y5T x1iI4D53PD/lTFCQrtdrfzHmR9FdY9cbaZC7PxWrkre1Oc12kegT0SmS2SksZJtLbV tYptqHtYhdo/+iY9fnfUcLYfVLa+EPE+VsR6xSgE= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ronnie Sahlberg , Steve French , Sasha Levin , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org Subject: [PATCH AUTOSEL 4.9 123/141] cifs: fix NULL dereference in match_prepath Date: Fri, 14 Feb 2020 11:21:03 -0500 Message-Id: <20200214162122.19794-123-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214162122.19794-1-sashal@kernel.org> References: <20200214162122.19794-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org From: Ronnie Sahlberg [ Upstream commit fe1292686333d1dadaf84091f585ee903b9ddb84 ] RHBZ: 1760879 Fix an oops in match_prepath() by making sure that the prepath string is not NULL before we pass it into strcmp(). This is similar to other checks we make for example in cifs_root_iget() Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/cifs/connect.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 751bdde6515d5..961fcb40183a4 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -2927,8 +2927,10 @@ match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data) { struct cifs_sb_info *old = CIFS_SB(sb); struct cifs_sb_info *new = mnt_data->cifs_sb; - bool old_set = old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH; - bool new_set = new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH; + bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) && + old->prepath; + bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) && + new->prepath; if (old_set && new_set && !strcmp(new->prepath, old->prepath)) return 1; -- 2.20.1