From patchwork Thu Mar 14 07:50:40 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kangjie Lu X-Patchwork-Id: 10852283 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 21A2C14DE for ; Thu, 14 Mar 2019 07:50:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 126872A23F for ; Thu, 14 Mar 2019 07:50:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 06B282A251; Thu, 14 Mar 2019 07:50:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A4F392A23F for ; Thu, 14 Mar 2019 07:50:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726654AbfCNHut (ORCPT ); Thu, 14 Mar 2019 03:50:49 -0400 Received: from mta-p6.oit.umn.edu ([134.84.196.206]:59806 "EHLO mta-p6.oit.umn.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726284AbfCNHut (ORCPT ); Thu, 14 Mar 2019 03:50:49 -0400 Received: from localhost (unknown [127.0.0.1]) by mta-p6.oit.umn.edu (Postfix) with ESMTP id 21CF7C6E for ; Thu, 14 Mar 2019 07:50:48 +0000 (UTC) X-Virus-Scanned: amavisd-new at umn.edu Received: from mta-p6.oit.umn.edu ([127.0.0.1]) by localhost (mta-p6.oit.umn.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ORWZY6UTvClw 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-p6.oit.umn.edu (Postfix) with ESMTPS id EC7E7C50 for ; Thu, 14 Mar 2019 02:50:47 -0500 (CDT) Received: by mail-io1-f71.google.com with SMTP id k2so3690499ioj.2 for ; Thu, 14 Mar 2019 00:50:47 -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=IaKKjQ9TBPeUqOV5bW0I+8ZCYcVy7kWY79eyGWcXNpNac3URCUqGap8eCajCZX3pJN g1J+rxvJ7YCtc0BD9FUNZsjDB/gxN9zVj0VzGSm+dwWenyXRV2Ii03NGoqDcO04yQB8t HXoC9lO1hQtiw2GLrYPkteiFFv1tRwKXAKClOeZZ81IeeQRd5gl7kGtknSIfzH6okfZ8 FwwzD0bzc46APRLuTZbRwD+sDrdXFWQR51a57NXKi8Sqk5Kmq3B4OAfy3ZPlZy+11/t1 zhx/Am7+mtPe7BbRQRFAxsggDia6Ud12eQbqNphRfKY2KNEJBqGPiVzm/+LlKSOHWQ8F sKVQ== X-Gm-Message-State: APjAAAWnADfM0UhKFXGcHWQl0Ioy/KnVHyLfe3pH7Cm173Vg140j3r9p 5gF+JGI4b2YR/Ug/KU0NzlFGw+/UYVJFGI6vNWkPrYBmW7AytoSTyH9ybjKyS3E1m5HoFI6PtRl ITk+4XS9ll5RcwoYQmLQT6nizqkU= X-Received: by 2002:a24:29c8:: with SMTP id p191mr1116832itp.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-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 Reviewed-by: Qu Wenruo --- 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,