BUG: memory leak
unreferenced object 0xffff88800fad1d60 (size 16):
  comm "syz-executor.4", pid 601, jiffies 4297760356 (age 18.685s)
  hex dump (first 16 bytes):
    28 08 4c 19 80 88 ff ff 00 60 9a 48 80 88 ff ff  (.L......`.H....
  backtrace:
    [<00000000cf7181ce>] kmalloc include/linux/slab.h:552 [inline]
    [<00000000cf7181ce>] ext4_multi_mount_protect+0x861/0xb20 fs/ext4/mmp.c:367
    [<0000000014183712>] ext4_fill_super+0xa20e/0xcf20 fs/ext4/super.c:4774
    [<000000005cce18c8>] mount_bdev+0x331/0x3f0 fs/super.c:1419
    [<00000000580e2f17>] legacy_get_tree+0x105/0x220 fs/fs_context.c:592
    [<00000000a65ed36f>] vfs_get_tree+0x8e/0x2f0 fs/super.c:1549
    [<000000006f8844a1>] do_new_mount fs/namespace.c:2881 [inline]
    [<000000006f8844a1>] path_mount+0x139a/0x2080 fs/namespace.c:3211
    [<00000000ca14e33b>] do_mount fs/namespace.c:3224 [inline]
    [<00000000ca14e33b>] __do_sys_mount fs/namespace.c:3432 [inline]
    [<00000000ca14e33b>] __se_sys_mount fs/namespace.c:3409 [inline]
    [<00000000ca14e33b>] __x64_sys_mount+0x27e/0x300 fs/namespace.c:3409
    [<00000000dec942d6>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
    [<00000000fa37d277>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: leak checking failed