BUG: memory leak
unreferenced object 0xffff888124856b40 (size 32):
  comm "syz-executor.1", pid 10871, jiffies 4294982694 (age 8.950s)
  hex dump (first 32 bytes):
    38 d1 b4 0f 81 88 ff ff 00 50 18 26 81 88 ff ff  8........P.&....
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000006434afaf>] kmalloc include/linux/slab.h:552 [inline]
    [<000000006434afaf>] ext4_multi_mount_protect+0x4a6/0x5d0 fs/ext4/mmp.c:367
    [<0000000016c068eb>] ext4_fill_super+0x5650/0x5ad0 fs/ext4/super.c:4768
    [<00000000fed8ffaa>] mount_bdev+0x223/0x260 fs/super.c:1366
    [<00000000fd3d8ec9>] legacy_get_tree+0x2b/0x90 fs/fs_context.c:592
    [<00000000e54a5daa>] vfs_get_tree+0x28/0x100 fs/super.c:1496
    [<00000000a17d3824>] do_new_mount fs/namespace.c:2881 [inline]
    [<00000000a17d3824>] path_mount+0xc5e/0x1170 fs/namespace.c:3211
    [<00000000b61dd743>] do_mount fs/namespace.c:3224 [inline]
    [<00000000b61dd743>] __do_sys_mount fs/namespace.c:3432 [inline]
    [<00000000b61dd743>] __se_sys_mount fs/namespace.c:3409 [inline]
    [<00000000b61dd743>] __x64_sys_mount+0x18e/0x1d0 fs/namespace.c:3409
    [<00000000c9c298cc>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
    [<00000000bd19ecb6>] entry_SYSCALL_64_after_hwframe+0x44/0xa9