[PATCH] btrfs: fix uninitialized pointer free on add_inode_ref

[Roi Martin <jroi.martin@gmail.com>]

The "add_inode_ref" function does not initializes the "name" struct
when it is declared.  If any of the following calls to
"read_one_inode" returns NULL,

	dir = read_one_inode(root, parent_objectid);
	if (!dir) {
		ret = -ENOENT;
		goto out;
	}

	inode = read_one_inode(root, inode_objectid);
	if (!inode) {
		ret = -EIO;
		goto out;
	}

then "name.name" would be freed on "out" before being initialized.

out:
	...
	kfree(name.name);

This issue was reported by Coverity with CID 1526744.

Signed-off-by: Roi Martin <jroi.martin@gmail.com>
---
 fs/btrfs/tree-log.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index e2ed2a791f8f..35c452bab1ca 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -1374,7 +1374,7 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
 	struct inode *inode = NULL;
 	unsigned long ref_ptr;
 	unsigned long ref_end;
-	struct fscrypt_str name;
+	struct fscrypt_str name = { 0 };
 	int ret;
 	int log_ref_ver = 0;
 	u64 parent_objectid;

base-commit: 75b607fab38d149f232f01eae5e6392b394dd659
-- 
2.46.0