From 56a0e706fcf870270878d6d72b71092ae42d229c Mon Sep 17 00:00:00 2001 From: Liu Bo Date: Mon, 30 Oct 2017 11:14:38 -0600 Subject: Btrfs: bail out gracefully rather than BUG_ON If a file's DIR_ITEM key is invalid (due to memory errors) and gets written to disk, a future lookup_path can end up with kernel panic due to BUG_ON(). This gets rid of the BUG_ON(), meanwhile output the corrupted key and return ENOENT if it's invalid. Signed-off-by: Liu Bo Reported-by: Guillaume Bouchard Signed-off-by: David Sterba --- fs/btrfs/inode.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 8525a44a607e..1131db7a0b28 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5445,6 +5445,14 @@ static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry, goto out_err; btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); + if (location->type != BTRFS_INODE_ITEM_KEY && + location->type != BTRFS_ROOT_ITEM_KEY) { + btrfs_warn(root->fs_info, +"%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))", + __func__, name, btrfs_ino(BTRFS_I(dir)), + location->objectid, location->type, location->offset); + goto out_err; + } out: btrfs_free_path(path); return ret; @@ -5761,8 +5769,6 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) return inode; } - BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); - index = srcu_read_lock(&fs_info->subvol_srcu); ret = fixup_tree_root_location(fs_info, dir, dentry, &location, &sub_root); -- cgit v1.2.3