From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xu Wen , Qu Wenruo , David Sterba , Sasha Levin Subject: [PATCH 4.18 133/197] btrfs: Exit gracefully when chunk map cannot be inserted to the tree Date: Thu, 13 Sep 2018 15:31:22 +0200 Message-Id: <20180913131846.882504917@linuxfoundation.org> In-Reply-To: <20180913131841.568116777@linuxfoundation.org> References: <20180913131841.568116777@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Qu Wenruo [ Upstream commit 64f64f43c89aca1782aa672e0586f6903c5d8979 ] It's entirely possible that a crafted btrfs image contains overlapping chunks. Although we can't detect such problem by tree-checker, it's not a catastrophic problem, current extent map can already detect such problem and return -EEXIST. We just only need to exit gracefully and fail the mount. Reported-by: Xu Wen Link: https://bugzilla.kernel.org/show_bug.cgi?id=200409 Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/volumes.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6563,10 +6563,14 @@ static int read_one_chunk(struct btrfs_f write_lock(&map_tree->map_tree.lock); ret = add_extent_mapping(&map_tree->map_tree, em, 0); write_unlock(&map_tree->map_tree.lock); - BUG_ON(ret); /* Tree corruption */ + if (ret < 0) { + btrfs_err(fs_info, + "failed to add chunk map, start=%llu len=%llu: %d", + em->start, em->len, ret); + } free_extent_map(em); - return 0; + return ret; } static void fill_device_from_item(struct extent_buffer *leaf,