BUG: memory leak
unreferenced object 0xffff888016d44b60 (size 16):
  comm "syz-executor.4", pid 7748, jiffies 4295298394 (age 17.637s)
  hex dump (first 16 bytes):
    e0 2a 74 19 80 88 ff ff 00 80 05 46 80 88 ff ff  .*t........F....
  backtrace:
    [<00000000d820632e>] kmalloc include/linux/slab.h:552 [inline]
    [<00000000d820632e>] ext4_multi_mount_protect+0x861/0xb20 fs/ext4/mmp.c:367
    [<00000000b5adf42e>] ext4_fill_super+0xa20e/0xcf20 fs/ext4/super.c:4774
    [<000000001de9908b>] mount_bdev+0x331/0x3f0 fs/super.c:1419
    [<0000000009302788>] legacy_get_tree+0x105/0x220 fs/fs_context.c:592
    [<0000000077b233ac>] vfs_get_tree+0x8e/0x2f0 fs/super.c:1549
    [<000000004ce1bc69>] do_new_mount fs/namespace.c:2881 [inline]
    [<000000004ce1bc69>] path_mount+0x139a/0x2080 fs/namespace.c:3211
    [<00000000ae57cbc2>] do_mount fs/namespace.c:3224 [inline]
    [<00000000ae57cbc2>] __do_sys_mount fs/namespace.c:3432 [inline]
    [<00000000ae57cbc2>] __se_sys_mount fs/namespace.c:3409 [inline]
    [<00000000ae57cbc2>] __x64_sys_mount+0x27e/0x300 fs/namespace.c:3409
    [<00000000cc753b39>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
    [<00000000bd29ed8a>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: leak checking failed