BUG: memory leak
unreferenced object 0xffff888021c1f740 (size 16):
  comm "syz-executor.6", pid 4713, jiffies 4294864277 (age 17.012s)
  hex dump (first 16 bytes):
    10 09 0f 46 80 88 ff ff 00 60 c6 34 80 88 ff ff  ...F.....`.4....
  backtrace:
    [<00000000cfe2217c>] kmalloc include/linux/slab.h:552 [inline]
    [<00000000cfe2217c>] ext4_multi_mount_protect+0x861/0xb20 fs/ext4/mmp.c:367
    [<00000000257db5f4>] ext4_fill_super+0xa20e/0xcf20 fs/ext4/super.c:4774
    [<00000000a78f581f>] mount_bdev+0x331/0x3f0 fs/super.c:1419
    [<000000000d4453c0>] legacy_get_tree+0x105/0x220 fs/fs_context.c:592
    [<00000000d16b3037>] vfs_get_tree+0x8e/0x2f0 fs/super.c:1549
    [<00000000ea50e56e>] do_new_mount fs/namespace.c:2881 [inline]
    [<00000000ea50e56e>] path_mount+0x139a/0x2080 fs/namespace.c:3211
    [<00000000cb9297b5>] do_mount fs/namespace.c:3224 [inline]
    [<00000000cb9297b5>] __do_sys_mount fs/namespace.c:3432 [inline]
    [<00000000cb9297b5>] __se_sys_mount fs/namespace.c:3409 [inline]
    [<00000000cb9297b5>] __x64_sys_mount+0x27e/0x300 fs/namespace.c:3409
    [<00000000c73370ae>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
    [<000000007dcc86ee>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: leak checking failed