From patchwork Wed Oct 9 16:43:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Filipe Manana X-Patchwork-Id: 11181571 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 941A81668 for ; Wed, 9 Oct 2019 16:44:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B8BF21848 for ; Wed, 9 Oct 2019 16:44:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570639443; bh=7yDuSgFw56bj5l3Ep2A4zgGcqqGgBxVs1K4XpTHzQBQ=; h=From:To:Subject:Date:List-ID:From; b=Aow8oBM7pSfGYISIigkizhPnmQBTt9kFKHxVS4S34Z0R095FQbzB9ZbCr3q39FON0 vPbfj0hGt0ONYmYhhdhe7SwQnM2ivmE9wopGTBSGykgZJ26EZkPs05nH640CJG8Ov4 +n1lJ/0w/fdrofI3mvPvmLeF9m0tqYd8cCL9BP9Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731720AbfJIQoC (ORCPT ); Wed, 9 Oct 2019 12:44:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:55590 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731636AbfJIQoC (ORCPT ); Wed, 9 Oct 2019 12:44:02 -0400 Received: from localhost.localdomain (bl8-197-74.dsl.telepac.pt [85.241.197.74]) (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 6D6CD206BB for ; Wed, 9 Oct 2019 16:44:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570639441; bh=7yDuSgFw56bj5l3Ep2A4zgGcqqGgBxVs1K4XpTHzQBQ=; h=From:To:Subject:Date:From; b=edIMQkokAkklU25mQLljxLiMDExgXcJ3mEqFBIjK0JbXTZWPXqinPsBp3Z8Bg+B2K l/QHgivfbSDpfqPnlq05p00eo7fNN8DkhWMhyAHMIfeOcEk99lncriuItW7ey86Sc6 HkwGWDqGkGSYxExGs1hNwuJEYLUrmI9PGA8d1HvA= From: fdmanana@kernel.org To: linux-btrfs@vger.kernel.org Subject: [PATCH] Btrfs: fix metadata space leak on fixup worker failure to set range as delalloc Date: Wed, 9 Oct 2019 17:43:59 +0100 Message-Id: <20191009164359.29642-1-fdmanana@kernel.org> X-Mailer: git-send-email 2.11.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Filipe Manana In the fixup worker, if we fail to mark the range as delalloc in the io tree, we must release the previously reserved metadata, as well as update the outstanding extents counter for the inode, otherwise we leak metadata space. In pratice we can't return an error from btrfs_set_extent_delalloc(), which is just a wrapper around __set_extent_bit(), as for most errors __set_extent_bit() does a BUG_ON() (or panics which hits a BUG_ON() as well) and returning an -EEXIST error doesn't happen in this case since the exclusive bits parameter always has a value of 0 through this code path. Nevertheless, just fix the error handling in the fixup worker, in case one day __set_extent_bit() can return an error to this code path. Fixes: f3038ee3a3f101 ("btrfs: Handle btrfs_set_extent_delalloc failure in fixup worker") Signed-off-by: Filipe Manana Reviewed-by: Nikolay Borisov --- fs/btrfs/inode.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 0f2754eaa05b..f23b14ec743a 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2201,12 +2201,16 @@ static void btrfs_writepage_fixup_worker(struct btrfs_work *work) mapping_set_error(page->mapping, ret); end_extent_writepage(page, ret, page_start, page_end); ClearPageChecked(page); - goto out; + goto out_reserved; } ClearPageChecked(page); set_page_dirty(page); - btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, false); +out_reserved: + btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, ret != 0); + if (ret) + btrfs_delalloc_release_space(inode, data_reserved, page_start, + PAGE_SIZE, true); out: unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, &cached_state);