Commit 145b1f56 authored Aug 01, 2018 by Qu Wenruo Committed by Greg Kroah-Hartman Sep 15, 2018

btrfs: Exit gracefully when chunk map cannot be inserted to the tree



[ 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@gatech.edu>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200409


Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 80f97c79

fs/btrfs/volumes.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -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,