We lookup the name of a subvol which means we'll cross into different
roots. Hold a ref while we're doing the look ups in the fs_root we're
searching.
Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
---
fs/btrfs/super.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 3118bc01321e..5c3a1b7de6ee 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1101,6 +1101,10 @@ static char *get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info,
ret = PTR_ERR(fs_root);
goto err;
}
+ if (!btrfs_grab_fs_root(fs_root)) {
+ ret = -ENOENT;
+ goto err;
+ }
/*
* Walk up the filesystem tree by inode refs until we hit the
@@ -1113,13 +1117,16 @@ static char *get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info,
ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0);
if (ret < 0) {
+ btrfs_put_fs_root(fs_root);
goto err;
} else if (ret > 0) {
ret = btrfs_previous_item(fs_root, path, dirid,
BTRFS_INODE_REF_KEY);
if (ret < 0) {
+ btrfs_put_fs_root(fs_root);
goto err;
} else if (ret > 0) {
+ btrfs_put_fs_root(fs_root);
ret = -ENOENT;
goto err;
}
@@ -1136,6 +1143,7 @@ static char *get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info,
ptr -= len + 1;
if (ptr < name) {
ret = -ENAMETOOLONG;
+ btrfs_put_fs_root(fs_root);
goto err;
}
read_extent_buffer(path->nodes[0], ptr + 1,
@@ -1143,6 +1151,7 @@ static char *get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info,
ptr[0] = '/';
btrfs_release_path(path);
}
+ btrfs_put_fs_root(fs_root);
}
btrfs_free_path(path);
--
2.24.1
