From: Josef Bacik <josef@toxicpanda.com>
Date: Fri, 24 Jan 2020 09:32:34 -0500
Git-commit: 88234012beaaf677dc6d3e685d270acc1bb56a03
Patch-mainline: 5.7-rc1
References: bsc#1176019
Subject: [PATCH] btrfs: hold a ref on the root in btrfs_search_path_in_tree

We look up an arbitrary fs root, we need to hold a ref on it while we're
doing our search.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/ioctl.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index b173bb6915d9..9c8a9944f848 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2328,6 +2328,12 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
 	root = btrfs_get_fs_root(info, &key, true);
 	if (IS_ERR(root)) {
 		ret = PTR_ERR(root);
+		root = NULL;
+		goto out;
+	}
+	if (!btrfs_grab_fs_root(root)) {
+		ret = -ENOENT;
+		root = NULL;
 		goto out;
 	}
 
@@ -2378,6 +2384,7 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
 	name[total_len] = '\0';
 	ret = 0;
 out:
+	btrfs_put_fs_root(root);
 	btrfs_free_path(path);
 	return ret;
 }
-- 
2.26.2