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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 624D4C43381 for ; Thu, 14 Mar 2019 07:50:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 29F782087C for ; Thu, 14 Mar 2019 07:50:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=umn.edu header.i=@umn.edu header.b="mc33nTd7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726828AbfCNHuu (ORCPT ); Thu, 14 Mar 2019 03:50:50 -0400 Received: from mta-p8.oit.umn.edu ([134.84.196.208]:60036 "EHLO mta-p8.oit.umn.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726539AbfCNHut (ORCPT ); Thu, 14 Mar 2019 03:50:49 -0400 Received: from localhost (unknown [127.0.0.1]) by mta-p8.oit.umn.edu (Postfix) with ESMTP id 34461C43 for ; Thu, 14 Mar 2019 07:50:48 +0000 (UTC) X-Virus-Scanned: amavisd-new at umn.edu Received: from mta-p8.oit.umn.edu ([127.0.0.1]) by localhost (mta-p8.oit.umn.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jeB4Ymar3-cf for ; Thu, 14 Mar 2019 02:50:48 -0500 (CDT) Received: from mail-io1-f71.google.com (mail-io1-f71.google.com [209.85.166.71]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mta-p8.oit.umn.edu (Postfix) with ESMTPS id 083A096D for ; Thu, 14 Mar 2019 02:50:48 -0500 (CDT) Received: by mail-io1-f71.google.com with SMTP id i1so3735509ioq.9 for ; Thu, 14 Mar 2019 00:50:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=umn.edu; s=google; h=from:to:cc:subject:date:message-id; bh=DLANtRSSRHAl4T+X5AQuykmiffSXk6BE1bjRT1gOrDw=; b=mc33nTd7ZZ/PlEGWW5dq7jTiyDDeuhuqTkgvkT7UUjPuf9mlfb0OYOD2WSuMx7mMYL k27rZu7mjFY8Hat9LMZMSNWz9ebkb88gdOs/lvkOduofrXPwfR5vW5Ppon58sXNYaFiU M9mGXzggJEFRBsy+yTbckhYhrxRDeUfmJW5j67LuKN9yABTKQCOUV4GR4GGjw7xnpN1c jdcTYMS072mAsXq8Tuu130+wKC4RsMBaNxQHHbJCUblLR/hdjPytSi09CixubKD9MY2Z n33Y3Vrx0Y8pxAZj7zec+DRcVbFH9iS2ZeqBFK3z5Xy08gIhYk4oMOIyHMFWtOwlIDfv C/KQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=DLANtRSSRHAl4T+X5AQuykmiffSXk6BE1bjRT1gOrDw=; b=DwnLt1opEkOjEs6QllX1WhV5lFzc9gYHP7SqoRLriawh4JzwsvVIjWSuyDGmiBZL6P UjfEwl6Z3+CvK2B9dHdWMnZ00vO8t4RUCRWAckMLBwD5TuK6QOwU6iXRnQrMO/1jxw4o dojItA9rCQ+4tBwHn+FSqKZzTENT1sJV4l1exS1MLY9LUwgKGGAq+YbTxWeKLEdrMqZS fFoYb//ZORKCiqvl6VHgGaCQF9WC6kOmkiCr7Z2jh8OZ5CNWOLj92Uq9dT0SwDKwtCWf P4591TB1hsdYrRE7ydCWoXPIfHAjYkfZ1b8JI8BxqAMNvSg3rdzRGMaWgIogfX4FNRLX UlQQ== X-Gm-Message-State: APjAAAUrSLy8izTDc9CqebxwK75GATcCSjNkuZELqcUZbnZhokj4wBWN G99+8zTGXGAhmAJDkYFHTkp09Gr1vyJMI69HyLlQPpAfSGb1I68ZxufJE4TSChr+9aQAvvfnv04 8nsTdKPStAOL8QaGVHZ5XywORSUTa X-Received: by 2002:a24:29c8:: with SMTP id p191mr1116834itp.115.1552549847615; Thu, 14 Mar 2019 00:50:47 -0700 (PDT) X-Google-Smtp-Source: APXvYqwkfCVvG2ptR02yE3dTQHdvKlnANoVN72gvCgb3pCVla2WLuPN1hMoGboIrjjpRk4TFMRVtmA== X-Received: by 2002:a24:29c8:: with SMTP id p191mr1116826itp.115.1552549847379; Thu, 14 Mar 2019 00:50:47 -0700 (PDT) Received: from bee.dtc.umn.edu (cs-bee-u.cs.umn.edu. [128.101.106.63]) by smtp.gmail.com with ESMTPSA id k4sm820334itc.32.2019.03.14.00.50.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 14 Mar 2019 00:50:46 -0700 (PDT) From: Kangjie Lu To: kjlu@umn.edu Cc: pakki001@umn.edu, Chris Mason , Josef Bacik , David Sterba , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] btrfs: fix a NULL pointer dereference Date: Thu, 14 Mar 2019 02:50:40 -0500 Message-Id: <20190314075041.28966-1-kjlu@umn.edu> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org btrfs_lookup_block_group may fail and return NULL. The fix goes to out when it fails to avoid NULL pointer dereference. Signed-off-by: Kangjie Lu --- fs/btrfs/extent-tree.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 994f0cc41799..b1e7985bcb9d 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7303,6 +7303,8 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, pin = 0; cache = btrfs_lookup_block_group(fs_info, buf->start); + if (!cache) + goto out; if (btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { pin_down_extent(fs_info, cache, buf->start, -- 2.17.1