BUG: memory leak
unreferenced object 0xffff888125bbf720 (size 32):
  comm "syz-executor.3", pid 10888, jiffies 4294983369 (age 10.770s)
  hex dump (first 32 bytes):
    00 f0 13 0f 81 88 ff ff 00 18 3c 25 81 88 ff ff  ..........<%....
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000049462d7f>] kmalloc include/linux/slab.h:552 [inline]
    [<0000000049462d7f>] ext4_multi_mount_protect+0x4a6/0x5d0 fs/ext4/mmp.c:367
    [<000000006eae502a>] ext4_fill_super+0x5650/0x5ad0 fs/ext4/super.c:4728
    [<00000000d2fb0799>] mount_bdev+0x223/0x260 fs/super.c:1366
    [<0000000063b78d37>] legacy_get_tree+0x2b/0x90 fs/fs_context.c:592
    [<000000000c7bd64f>] vfs_get_tree+0x28/0x100 fs/super.c:1496
    [<0000000020dc4e38>] do_new_mount fs/namespace.c:2878 [inline]
    [<0000000020dc4e38>] path_mount+0xc5e/0x1170 fs/namespace.c:3208
    [<00000000fb5565dd>] do_mount fs/namespace.c:3221 [inline]
    [<00000000fb5565dd>] __do_sys_mount fs/namespace.c:3429 [inline]
    [<00000000fb5565dd>] __se_sys_mount fs/namespace.c:3406 [inline]
    [<00000000fb5565dd>] __x64_sys_mount+0x18e/0x1d0 fs/namespace.c:3406
    [<0000000087758155>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
    [<00000000fd0d63ef>] entry_SYSCALL_64_after_hwframe+0x44/0xa9