Re: [syzbot] [fscrypt?] [f2fs?] memory leak in fscrypt_setup_filename

[Eric Biggers <ebiggers@kernel.org>]

On Tue, Mar 03, 2026 at 02:25:37PM -0800, syzbot wrote:
> 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

The following commit added a call to f2fs_setup_filename() without a
matching call to f2fs_free_filename():

    commit 40b2d55e045222dd6de2a54a299f682e0f954b03
    Author: Chao Yu <chao@kernel.org>
    Date:   Wed Feb 7 15:05:48 2024 +0800

        f2fs: fix to create selinux label during whiteout initialization

Chao, do you want to handle fixing this?

- Eric