[PATCH] btrfs: fix uninitialized pointer free on add_inode_ref

From: Roi Martin
Date: Wed Oct 09 2024 - 04:09:15 EST


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@xxxxxxxxx>
---
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