BUG: memory leak
unreferenced object 0xffff8880476090a0 (size 16):
  comm "syz-executor.6", pid 32169, jiffies 4297840930 (age 26.519s)
  hex dump (first 16 bytes):
    10 79 94 42 80 88 ff ff 00 80 18 50 80 88 ff ff  .y.B.......P....
  backtrace:
    [<000000003cb59540>] kmalloc include/linux/slab.h:552 [inline]
    [<000000003cb59540>] ext4_multi_mount_protect+0x861/0xb20 fs/ext4/mmp.c:367
    [<00000000fd6e726f>] ext4_fill_super+0xa20e/0xcf20 fs/ext4/super.c:4774
    [<00000000fa824e48>] mount_bdev+0x331/0x3f0 fs/super.c:1419
    [<00000000081afd00>] legacy_get_tree+0x105/0x220 fs/fs_context.c:592
    [<000000001d652396>] vfs_get_tree+0x8e/0x2f0 fs/super.c:1549
    [<000000008d142500>] do_new_mount fs/namespace.c:2881 [inline]
    [<000000008d142500>] path_mount+0x139a/0x2080 fs/namespace.c:3211
    [<000000002bff8795>] do_mount fs/namespace.c:3224 [inline]
    [<000000002bff8795>] __do_sys_mount fs/namespace.c:3432 [inline]
    [<000000002bff8795>] __se_sys_mount fs/namespace.c:3409 [inline]
    [<000000002bff8795>] __x64_sys_mount+0x27e/0x300 fs/namespace.c:3409
    [<00000000d8d6df2f>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
    [<00000000abf5332c>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: leak checking failed