BUG: memory leak
unreferenced object 0xffff8880221148a0 (size 16):
  comm "syz-executor.5", pid 26998, jiffies 4296085217 (age 18.300s)
  hex dump (first 16 bytes):
    b0 9c 46 42 80 88 ff ff 00 60 48 49 80 88 ff ff  ..FB.....`HI....
  backtrace:
    [<000000009f979bb4>] kmalloc include/linux/slab.h:552 [inline]
    [<000000009f979bb4>] ext4_multi_mount_protect+0x861/0xb20 fs/ext4/mmp.c:367
    [<000000004bba58f3>] ext4_fill_super+0xa20e/0xcf20 fs/ext4/super.c:4774
    [<000000000a34aea4>] mount_bdev+0x331/0x3f0 fs/super.c:1419
    [<0000000010545ae4>] legacy_get_tree+0x105/0x220 fs/fs_context.c:592
    [<0000000045ee1d0b>] vfs_get_tree+0x8e/0x2f0 fs/super.c:1549
    [<00000000359ca02a>] do_new_mount fs/namespace.c:2881 [inline]
    [<00000000359ca02a>] path_mount+0x139a/0x2080 fs/namespace.c:3211
    [<00000000740e1ff2>] do_mount fs/namespace.c:3224 [inline]
    [<00000000740e1ff2>] __do_sys_mount fs/namespace.c:3432 [inline]
    [<00000000740e1ff2>] __se_sys_mount fs/namespace.c:3409 [inline]
    [<00000000740e1ff2>] __x64_sys_mount+0x27e/0x300 fs/namespace.c:3409
    [<000000007994c823>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
    [<0000000013f1e953>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

BUG: leak checking failed