BUG: memory leak
unreferenced object 0xffff888021cffaa0 (size 16):
  comm "syz-executor.3", pid 9401, jiffies 4295807463 (age 19.247s)
  hex dump (first 16 bytes):
    a0 53 9f 20 80 88 ff ff 00 40 a4 42 80 88 ff ff  .S. .....@.B....
  backtrace:
    [<00000000df27ffe1>] kmalloc include/linux/slab.h:552 [inline]
    [<00000000df27ffe1>] ext4_multi_mount_protect+0x861/0xb20 fs/ext4/mmp.c:367
    [<000000001dc193a9>] ext4_fill_super+0xa20e/0xcf20 fs/ext4/super.c:4774
    [<00000000099576d7>] mount_bdev+0x331/0x3f0 fs/super.c:1419
    [<00000000d4a04d1c>] legacy_get_tree+0x105/0x220 fs/fs_context.c:592
    [<00000000b4c24496>] vfs_get_tree+0x8e/0x2f0 fs/super.c:1549
    [<0000000075897bad>] do_new_mount fs/namespace.c:2881 [inline]
    [<0000000075897bad>] path_mount+0x139a/0x2080 fs/namespace.c:3211
    [<00000000ba83144e>] do_mount fs/namespace.c:3224 [inline]
    [<00000000ba83144e>] __do_sys_mount fs/namespace.c:3432 [inline]
    [<00000000ba83144e>] __se_sys_mount fs/namespace.c:3409 [inline]
    [<00000000ba83144e>] __x64_sys_mount+0x27e/0x300 fs/namespace.c:3409
    [<00000000f08d59a3>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
    [<000000006b37d9d8>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: leak checking failed