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

[Chao Yu <chao@kernel.org>]

#syz test: https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git bugfix/syzbot

On 2026/3/4 06:25, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    af4e9ef3d784 uaccess: Fix scoped_user_read_access() for 'p..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=12506d5a580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=2c6ad6fefffa76b1
> dashboard link: https://syzkaller.appspot.com/bug?extid=cf7946ab25b21abc4b66
> compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=160a18d6580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14e2b0ba580000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/70cb2ebe1e6e/disk-af4e9ef3.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/945fea3c8a6d/vmlinux-af4e9ef3.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/fa6a6a5cbcc8/bzImage-af4e9ef3.xz
> mounted in repro: https://storage.googleapis.com/syzbot-assets/c12ae92fa9b6/mount_0.gz
>    fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=10e1d202580000)
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+cf7946ab25b21abc4b66@syzkaller.appspotmail.com
> 
> 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
> 
> connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF
> 
> 
> ---
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