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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 D7C07C282DD for ; Wed, 22 May 2019 19:40:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A888120675 for ; Wed, 22 May 2019 19:40:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558554030; bh=tT1XJYwMVrZZz9et0vtMrBF2skqe3DiQHfOYqhZBQ8Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fPh2LGzvww4WX1OR9RMliTC9JnOd/zkWCsmSZETQmBloaH3a3NvAPv4DQjHy8XwP7 Fy70iDy9wYbdfoz8m2FuHQg6FuILvx9yVXDiGd5JcItrUXdVqodItOyKYKlKmVsziX WxvThKlY1XOZUnTbYFGx6xMiYKX1DhZFnkpPZ2Zs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732885AbfEVT32 (ORCPT ); Wed, 22 May 2019 15:29:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:52432 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732832AbfEVT3Z (ORCPT ); Wed, 22 May 2019 15:29:25 -0400 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 9D256217F9; Wed, 22 May 2019 19:29:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558553364; bh=tT1XJYwMVrZZz9et0vtMrBF2skqe3DiQHfOYqhZBQ8Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SL5Z0TorUJKNiX2Nrz3zUHXedX1sVl3xyq2dAydeRFHXB5DN/dosXcYIF1F0t8HH7 nMumE1yVkVNkFkCSGJiTyBuMSuodT86u5gEFRx/VMnsBhNglxRc0DBwaHMcctHkGTU LT0/GEFTu7cjkEwnP4kAC/tEBzYAwHxiUxevPAzU= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Robbie Ko , Filipe Manana , David Sterba , Sasha Levin , linux-btrfs@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 026/167] Btrfs: fix data bytes_may_use underflow with fallocate due to failed quota reserve Date: Wed, 22 May 2019 15:26:21 -0400 Message-Id: <20190522192842.25858-26-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190522192842.25858-1-sashal@kernel.org> References: <20190522192842.25858-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Robbie Ko [ Upstream commit 39ad317315887c2cb9a4347a93a8859326ddf136 ] When doing fallocate, we first add the range to the reserve_list and then reserve the quota. If quota reservation fails, we'll release all reserved parts of reserve_list. However, cur_offset is not updated to indicate that this range is already been inserted into the list. Therefore, the same range is freed twice. Once at list_for_each_entry loop, and once at the end of the function. This will result in WARN_ON on bytes_may_use when we free the remaining space. At the end, under the 'out' label we have a call to: btrfs_free_reserved_data_space(inode, data_reserved, alloc_start, alloc_end - cur_offset); The start offset, third argument, should be cur_offset. Everything from alloc_start to cur_offset was freed by the list_for_each_entry_safe_loop. Fixes: 18513091af94 ("btrfs: update btrfs_space_info's bytes_may_use timely") Reviewed-by: Filipe Manana Signed-off-by: Robbie Ko Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 57e25e83b81a8..7d99f36af100e 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -2964,6 +2964,7 @@ static long btrfs_fallocate(struct file *file, int mode, ret = btrfs_qgroup_reserve_data(inode, &data_reserved, cur_offset, last_byte - cur_offset); if (ret < 0) { + cur_offset = last_byte; free_extent_map(em); break; } @@ -3034,7 +3035,7 @@ static long btrfs_fallocate(struct file *file, int mode, /* Let go of our reservation. */ if (ret != 0) btrfs_free_reserved_data_space(inode, data_reserved, - alloc_start, alloc_end - cur_offset); + cur_offset, alloc_end - cur_offset); extent_changeset_free(data_reserved); return ret; } -- 2.20.1