From: Qu Wenruo <wqu@xxxxxxxx> [ 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 <wen.xu@xxxxxxxxxx> Link: https://bugzilla.kernel.org/show_bug.cgi?id=200409 Signed-off-by: Qu Wenruo <wqu@xxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> --- fs/btrfs/volumes.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 08afafb6ecf7..a39b1f0b0606 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6492,10 +6492,14 @@ static int read_one_chunk(struct btrfs_fs_info *fs_info, struct btrfs_key *key, 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, -- 2.17.1
