[PATCH 7.0 13/42] f2fs: fix to avoid memory leak in f2fs_rename()

Greg Kroah-Hartman
2026-04-24T13:32:08Z

From: Chao Yu <chao@kernel.org>

commit 3cf11e6f36c170050c12171dd6fd3142711478fc upstream.

syzbot reported a f2fs bug as below:

BUG: memory leak
unreferenced object 0xffff888127f70830 (size 16):
comm "syz.0.23", pid 6144, jiffies 4294943712
hex dump (first 16 bytes):
3c af 57 72 5b e6 8f ad 6e 8e fd 33 42 39 03 ff <.Wr[...n..3B9..
backtrace (crc 925f8a80):
kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
slab_post_alloc_hook mm/slub.c:4520 [inline]
slab_alloc_node mm/slub.c:4844 [inline]
__do_kmalloc_node mm/slub.c:5237 [inline]
__kmalloc_noprof+0x3bd/0x560 mm/slub.c:5250
kmalloc_noprof include/linux/slab.h:954 [inline]
fscrypt_setup_filename+0x15e/0x3b0 fs/crypto/fname.c:364
f2fs_setup_filename+0x52/0xb0 fs/f2fs/dir.c:143
f2fs_rename+0x159/0xca0 fs/f2fs/namei.c:961
f2fs_rename2+0xd5/0xf20 fs/f2fs/namei.c:1308
vfs_rename+0x7ff/0x1250 fs/namei.c:6026
filename_renameat2+0x4f4/0x660 fs/namei.c:6144
__do_sys_renameat2 fs/namei.c:6173 [inline]
__se_sys_renameat2 fs/namei.c:6168 [inline]
__x64_sys_renameat2+0x59/0x80 fs/namei.c:6168
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The root cause is in commit 40b2d55e0452 ("f2fs: fix to create selinux
label during whiteout initialization"), we added a call to
f2fs_setup_filename() without a matching call to f2fs_free_filename(),
fix it.

Fixes: 40b2d55e0452 ("f2fs: fix to create selinux label during whiteout initialization")
Cc: stable@kernel.org
Reported-by: syzbot+cf7946ab25b21abc4b66@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-f2fs-devel/69a75fe1.a70a0220.b118c.0014.GAE@google.com
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/f2fs/namei.c | 1 +
1 file changed, 1 insertion(+)

--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -964,6 +964,7 @@ static int f2fs_rename(struct mnt_idmap
return err;

err = f2fs_create_whiteout(idmap, old_dir, &whiteout, &fname);
+ f2fs_free_filename(&fname);
if (err)
return err;
}