From: David Sterba Date: Fri, 19 Jan 2024 19:44:57 +0000 (+0100) Subject: btrfs: handle invalid range and start in merge_extent_mapping() X-Git-Tag: v6.9-rc1~172^2~90 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c093bf306562c34d1c71f89897bb9220f44f5e4c;p=thirdparty%2Fkernel%2Flinux.git btrfs: handle invalid range and start in merge_extent_mapping() Turn a BUG_ON to a properly handled error and update the error message in the caller. It is expected that @em_in and @start passed to btrfs_add_extent_mapping() overlap. Besides tests, the only caller btrfs_get_extent() makes sure this is true. Reviewed-by: Josef Bacik Reviewed-by: Anand Jain Signed-off-by: David Sterba --- diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 1bf4d0319f6cb..ea08601988deb 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -538,7 +538,8 @@ static noinline int merge_extent_mapping(struct extent_map_tree *em_tree, u64 end; u64 start_diff; - BUG_ON(map_start < em->start || map_start >= extent_map_end(em)); + if (map_start < em->start || map_start >= extent_map_end(em)) + return -EINVAL; if (existing->start > map_start) { next = existing; @@ -633,9 +634,9 @@ int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info, free_extent_map(em); *em_in = NULL; WARN_ONCE(ret, -"unexpected error %d: merge existing(start %llu len %llu) with em(start %llu len %llu)\n", - ret, existing->start, existing->len, - orig_start, orig_len); +"extent map merge error existing [%llu, %llu) with em [%llu, %llu) start %llu\n", + existing->start, existing->len, + orig_start, orig_len, start); } free_extent_map(existing); }