[PATCH] fs/ntfs3: fix potential double iput on d_make_root() failure

Zhan Xusheng posted 1 patch 1 week ago
fs/ntfs3/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
[PATCH] fs/ntfs3: fix potential double iput on d_make_root() failure
Posted by Zhan Xusheng 1 week ago
d_make_root() consumes the reference to the passed inode: it either
attaches it to the newly created dentry on success, or drops it via
iput() on failure.

In the error path, the code currently does:
    sb->s_root = d_make_root(inode);
    if (!sb->s_root)
        goto put_inode_out;

which leads to a second iput(inode) in put_inode_out. This results in
a double iput and may trigger a use-after-free if the inode gets freed
after the first iput().

Fix this by jumping directly to the common cleanup path, avoiding the
extra iput(inode).

Signed-off-by: Zhan Xusheng <zhanxusheng@xiaomi.com>
---
 fs/ntfs3/super.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c
index 174a7cb202a0..d0dad15076ca 100644
--- a/fs/ntfs3/super.c
+++ b/fs/ntfs3/super.c
@@ -1673,7 +1673,7 @@ static int ntfs_fill_super(struct super_block *sb, struct fs_context *fc)
 	sb->s_root = d_make_root(inode);
 	if (!sb->s_root) {
 		err = -ENOMEM;
-		goto put_inode_out;
+		goto out;
 	}
 
 	if (boot2) {
-- 
2.43.0