Btrfs: fix error handling in __add_reloc_root()

We dereferenced "node" in the error message after freeing it.  Also
btrfs_panic() can return so we should return an error code instead of
continuing.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 646ee21..c5dbd91 100644 (file)
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1239,10 +1239,11 @@ static int __must_check __add_reloc_root(struct btrfs_root *root)
                              node->bytenr, &node->rb_node);
        spin_unlock(&rc->reloc_root_tree.lock);
        if (rb_node) {
-               kfree(node);
                btrfs_panic(root->fs_info, -EEXIST, "Duplicate root found "
                            "for start=%llu while inserting into relocation "
                            "tree\n");
+               kfree(node);
+               return -EEXIST;
        }
 
        list_add_tail(&root->root_list, &rc->reloc_roots);