[syzbot] memory leak in io_sqe_buffers_register

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    d2b6f8a1 Merge tag 'xfs-5.13-merge-3' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=173639a3d00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=337dc545ba10a406
dashboard link: https://syzkaller.appspot.com/bug?extid=0f32d05d8b6cd8d7ea3e
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14df6ba3d00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12815385d00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0f32d05d8b6cd8d7ea3e@xxxxxxxxxxxxxxxxxxxxxxxxx

Debian GNU/Linux 9 syzkaller ttyS0
Warning: Permanently added '10.128.1.62' (ECDSA) to the list of known hosts.
executing program
executing program
executing program
BUG: memory leak
unreferenced object 0xffff8881123bf0a0 (size 32):
  comm "syz-executor557", pid 8384, jiffies 4294946143 (age 12.360s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff81469b71>] kmalloc_node include/linux/slab.h:579 [inline]
    [<ffffffff81469b71>] kvmalloc_node+0x61/0xf0 mm/util.c:587
    [<ffffffff815f0b3f>] kvmalloc include/linux/mm.h:795 [inline]
    [<ffffffff815f0b3f>] kvmalloc_array include/linux/mm.h:813 [inline]
    [<ffffffff815f0b3f>] kvcalloc include/linux/mm.h:818 [inline]
    [<ffffffff815f0b3f>] io_rsrc_data_alloc+0x4f/0xc0 fs/io_uring.c:7164
    [<ffffffff815f26d8>] io_sqe_buffers_register+0x98/0x3d0 fs/io_uring.c:8383
    [<ffffffff815f84a7>] __io_uring_register+0xf67/0x18c0 fs/io_uring.c:9986
    [<ffffffff81609222>] __do_sys_io_uring_register fs/io_uring.c:10091 [inline]
    [<ffffffff81609222>] __se_sys_io_uring_register fs/io_uring.c:10071 [inline]
    [<ffffffff81609222>] __x64_sys_io_uring_register+0x112/0x230 fs/io_uring.c:10071
    [<ffffffff842f616a>] do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
    [<ffffffff84400068>] entry_SYSCALL_64_after_hwframe+0x44/0xae



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