BUG: memory leak
unreferenced object 0xffff88800c669680 (size 16):
  comm "syz-executor.7", pid 5346, jiffies 4294967363 (age 27.845s)
  hex dump (first 16 bytes):
    70 95 64 19 80 88 ff ff 00 a0 aa 40 80 88 ff ff  p.d........@....
  backtrace:
    [<00000000965a46a4>] kmalloc include/linux/slab.h:552 [inline]
    [<00000000965a46a4>] ext4_multi_mount_protect+0x861/0xb20 fs/ext4/mmp.c:367
    [<000000007201699a>] ext4_fill_super+0xa20e/0xcf20 fs/ext4/super.c:4774
    [<0000000080d7ab2f>] mount_bdev+0x331/0x3f0 fs/super.c:1419
    [<00000000396f44a9>] legacy_get_tree+0x105/0x220 fs/fs_context.c:592
    [<000000003be2360f>] vfs_get_tree+0x8e/0x2f0 fs/super.c:1549
    [<000000003f624a17>] do_new_mount fs/namespace.c:2881 [inline]
    [<000000003f624a17>] path_mount+0x139a/0x2080 fs/namespace.c:3211
    [<0000000060c046c0>] do_mount fs/namespace.c:3224 [inline]
    [<0000000060c046c0>] __do_sys_mount fs/namespace.c:3432 [inline]
    [<0000000060c046c0>] __se_sys_mount fs/namespace.c:3409 [inline]
    [<0000000060c046c0>] __x64_sys_mount+0x27e/0x300 fs/namespace.c:3409
    [<000000009334b47a>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
    [<0000000022f02fc5>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: leak checking failed