From 159f177cf93a235762dd9e776752cdfbda0dbb8c Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Thu, 5 Jul 2018 15:37:30 +0800 Subject: btrfs-progs: check/original: Avoid infinite loop when failed to repair inode Exposed by fuzz-tests/003-multi-check-unmounted/ on fuzzed image bko-161811.raw.xz. It's caused by the fact when check_fs_roots() finds tree root is modified, it re-search tree root by goto again: label. However again: label. will also reset root objectid to 0. If we failed to repair one fs root but still modified tree root, we will go into such infinite loop. Fix it by recording which root we should skip for repair mode. Signed-off-by: Qu Wenruo Reviewed-by: Gu Jinxiang Signed-off-by: David Sterba --- check/main.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) (limited to 'check') diff --git a/check/main.c b/check/main.c index 152eecec..b5ca6515 100644 --- a/check/main.c +++ b/check/main.c @@ -3398,6 +3398,7 @@ static int check_fs_roots(struct btrfs_fs_info *fs_info, struct extent_buffer *leaf, *tree_node; struct btrfs_root *tmp_root; struct btrfs_root *tree_root = fs_info->tree_root; + u64 skip_root = 0; int ret; int err = 0; @@ -3413,7 +3414,10 @@ static int check_fs_roots(struct btrfs_fs_info *fs_info, again: key.offset = 0; - key.objectid = 0; + if (skip_root) + key.objectid = skip_root + 1; + else + key.objectid = 0; key.type = BTRFS_ROOT_ITEM_KEY; ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0); if (ret < 0) { @@ -3422,6 +3426,7 @@ again: } tree_node = tree_root->node; while (1) { + if (tree_node != tree_root->node) { free_root_recs_tree(root_cache); btrfs_release_path(&path); @@ -3458,8 +3463,18 @@ again: btrfs_release_path(&path); goto again; } - if (ret) + if (ret) { err = 1; + + /* + * We failed to repair this root but modified + * tree root, after again: label we will still + * hit this root and fail to repair, so we must + * skip it to avoid infinite loop. + */ + if (repair) + skip_root = key.objectid; + } if (key.objectid == BTRFS_TREE_RELOC_OBJECTID) btrfs_free_fs_root(tmp_root); } else if (key.type == BTRFS_ROOT_REF_KEY || -- cgit v1.2.3