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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 D12F5C43381 for ; Tue, 12 Mar 2019 18:08:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A23BB2147C for ; Tue, 12 Mar 2019 18:08:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552414081; bh=q3kXbD1ysyQ7+orqua6uY2D+D/0ahDZ3k4nRiV7VkTA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=qJejZrckepeWGkHWIsXANz3M505x6UewcHjoaymSlWVUMadqDoNFAxD+5jjENsDCT xXS5//54f9XUmiTrHp4DsSK/ZytkkHmlmvYNDXWY96YSwBs7yZehvddDJwSyLH3aVz Z0FyEZgMMaCodTmcGtQu4+jQLcnuyjacYrEzf7bg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728156AbfCLSIA (ORCPT ); Tue, 12 Mar 2019 14:08:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:47224 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727372AbfCLRMS (ORCPT ); Tue, 12 Mar 2019 13:12:18 -0400 Received: from localhost (unknown [104.133.8.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 79DB12087C; Tue, 12 Mar 2019 17:12:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1552410737; bh=q3kXbD1ysyQ7+orqua6uY2D+D/0ahDZ3k4nRiV7VkTA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tUlN/GrX1uqDmFlhBtz36L4QiW0+3Nyf5bYTkcEAgpfT9bXpLgtNfQV5pI0Io2VNi aoUkzPt0vn4B28QOXYVUbaClFg14KwB5NWdrhly6Ui5c4O/MAlUQdvUUZJgqJqCXNW IhBphc2BROZwPef9CmWnINiLpT94Bh7rp9aH3rMs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yao Liu , Anna Schumaker , Sasha Levin Subject: [PATCH 4.20 040/171] nfs: Fix NULL pointer dereference of dev_name Date: Tue, 12 Mar 2019 10:07:00 -0700 Message-Id: <20190312170351.554683239@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190312170347.868927101@linuxfoundation.org> References: <20190312170347.868927101@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 80ff00172407e0aad4b10b94ef0816fc3e7813cb ] There is a NULL pointer dereference of dev_name in nfs_parse_devname() The oops looks something like: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 ... RIP: 0010:nfs_fs_mount+0x3b6/0xc20 [nfs] ... Call Trace: ? ida_alloc_range+0x34b/0x3d0 ? nfs_clone_super+0x80/0x80 [nfs] ? nfs_free_parsed_mount_data+0x60/0x60 [nfs] mount_fs+0x52/0x170 ? __init_waitqueue_head+0x3b/0x50 vfs_kern_mount+0x6b/0x170 do_mount+0x216/0xdc0 ksys_mount+0x83/0xd0 __x64_sys_mount+0x25/0x30 do_syscall_64+0x65/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fix this by adding a NULL check on dev_name Signed-off-by: Yao Liu Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin --- fs/nfs/super.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/nfs/super.c b/fs/nfs/super.c index 5ef2c71348bd..6b666d187907 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -1906,6 +1906,11 @@ static int nfs_parse_devname(const char *dev_name, size_t len; char *end; + if (unlikely(!dev_name || !*dev_name)) { + dfprintk(MOUNT, "NFS: device name not specified\n"); + return -EINVAL; + } + /* Is the host name protected with square brakcets? */ if (*dev_name == '[') { end = strchr(++dev_name, ']'); -- 2.19.1