> -----Original Message----- > From: linux-btrfs-ow...@vger.kernel.org > [mailto:linux-btrfs-ow...@vger.kernel.org] On Behalf Of Qu Wenruo > Sent: Thursday, July 05, 2018 3:38 PM > To: linux-btrfs@vger.kernel.org > Subject: [PATCH 3/4] 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: tag. > However again: tag 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 record which root we should skip for repair mode. > > Signed-off-by: Qu Wenruo <w...@suse.com> > --- > check/main.c | 19 +++++++++++++++++-- > 1 file changed, 17 insertions(+), 2 deletions(-) > > diff --git a/check/main.c b/check/main.c > index c8c347236543..2b5abb2d025b 100644 > --- a/check/main.c > +++ b/check/main.c > @@ -3380,6 +3380,7 @@ 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; > > @@ -3400,7 +3401,10 @@ 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) { > @@ -3409,6 +3413,7 @@ again: > } > tree_node = tree_root->node; > while (1) { > + > if (tree_node != tree_root->node) { > free_root_recs_tree(root_cache); > btrfs_release_path(&path); > @@ -3445,8 +3450,18 @@ 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: tag we will still hit this > + * root and fail to repair, must skip this root > 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 || > --
Reviewed-by: Gu Jinxiang <g...@cn.fujitsu.com> > 2.18.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
