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=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 A68BEC282CE for ; Wed, 22 May 2019 19:27:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7968C217D7 for ; Wed, 22 May 2019 19:27:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558553264; bh=Z0M1Ru0jdwl8r/WKfcgsUwrussyr67JIQ72gfQBLf24=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ev5mYv2K49O7bXZcGRHtsYftFF/WBt7D0Q4giMBxTg9AkORtJz0Wrx4D/7tuWGZdx 1db/qdsikleHakFgX4EGU9+yxdkBLhxw4SQy4Zt3f3rpbtaQ0txe0WCK8bRCm/lgLz +byVJ6IZQA8UyUsliwtqz5ldZ67GZpS/TpkLtlT8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732368AbfEVT1n (ORCPT ); Wed, 22 May 2019 15:27:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:49994 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730529AbfEVT1m (ORCPT ); Wed, 22 May 2019 15:27:42 -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 BC89F20675; Wed, 22 May 2019 19:27:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558553261; bh=Z0M1Ru0jdwl8r/WKfcgsUwrussyr67JIQ72gfQBLf24=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MfjZFSGKzUAz9cs07Lorn7RtSMByalzoUSc3nV7L0zbGddjvbPdGF0lKXj4zm/lIW vX5orcncL1xLcU8C5dv4kewlMYkpesGZ9+Zp16ACm9Aw2UOKObFy2GtTAWktApFmk+ Nf8HwZSKfKOEvI4bv2mE9tinVIq9C9mkDrB74ABY= 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 4.19 040/244] Btrfs: fix data bytes_may_use underflow with fallocate due to failed quota reserve Date: Wed, 22 May 2019 15:23:06 -0400 Message-Id: <20190522192630.24917-40-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190522192630.24917-1-sashal@kernel.org> References: <20190522192630.24917-1-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 ca4902c66dc43..868da8566f84c 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -3151,6 +3151,7 @@ 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; } @@ -3200,7 +3201,7 @@ static long btrfs_fallocate(struct file *file, int mode, /* Let go of our reservation. */ if (ret != 0 && !(mode & FALLOC_FL_ZERO_RANGE)) 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