[syzbot] [mm?] kernel BUG in sanity_check_pinned_pages

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    d7fa1af5b33e Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=1457d80c580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=89c13de706fbf07a
dashboard link: https://syzkaller.appspot.com/bug?extid=1d335893772467199ab6
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/da97ad659b2c/disk-d7fa1af5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/659e123552a8/vmlinux-d7fa1af5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6ec5dbf4643e/Image-d7fa1af5.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1d335893772467199ab6@xxxxxxxxxxxxxxxxxxxxxxxxx

head: ffffffff000001fe 0000000000000028 0000000000000000 0000000000000200
page dumped because: VM_BUG_ON_PAGE(!PageAnonExclusive(&folio->page) && !PageAnonExclusive(page))
------------[ cut here ]------------
kernel BUG at mm/gup.c:70!
Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
Modules linked in:

CPU: 1 UID: 0 PID: 115 Comm: kworker/u8:4 Not tainted 6.15.0-rc7-syzkaller-gd7fa1af5b33e #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: iou_exit io_ring_exit_work
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : sanity_check_pinned_pages+0x7cc/0x7d0 mm/gup.c:69
lr : sanity_check_pinned_pages+0x7cc/0x7d0 mm/gup.c:69
sp : ffff800097f17640
x29: ffff800097f17660 x28: dfff800000000000 x27: 1fffffbff87da000
x26: 05ffc0000002107c x25: 05ffc0000002107c x24: fffffdffc3ed0000
x23: fffffdffc3ed0000 x22: ffff800097f176e0 x21: 05ffc0000002107c
x20: 0000000000000000 x19: ffff800097f176e0 x18: 1fffe0003386f276
x17: 703e2d6f696c6f66 x16: ffff80008adbe9e4 x15: 0000000000000001
x14: 1fffe0003386f2e2 x13: 0000000000000000 x12: 0000000000000000
x11: ffff60003386f2e3 x10: 0000000000ff0100 x9 : c8ccd30be98f3f00
x8 : c8ccd30be98f3f00 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800097f16d58 x4 : ffff80008f415ba0 x3 : ffff8000807b4b68
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000061
Call trace:
 sanity_check_pinned_pages+0x7cc/0x7d0 mm/gup.c:69 (P)
 unpin_user_page+0x80/0x10c mm/gup.c:191
 io_release_ubuf+0x84/0xf8 io_uring/rsrc.c:113
 io_buffer_unmap io_uring/rsrc.c:140 [inline]
 io_free_rsrc_node+0x250/0x57c io_uring/rsrc.c:513
 io_put_rsrc_node io_uring/rsrc.h:103 [inline]
 io_rsrc_data_free+0x148/0x298 io_uring/rsrc.c:197
 io_sqe_buffers_unregister+0x84/0xa0 io_uring/rsrc.c:607
 io_ring_ctx_free+0x48/0x430 io_uring/io_uring.c:2723
 io_ring_exit_work+0x6c4/0x73c io_uring/io_uring.c:2962
 process_one_work+0x7e8/0x156c kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3400
 kthread+0x5fc/0x75c kernel/kthread.c:464
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847
Code: 900523a1 910e0021 aa1703e0 97fff8a9 (d4210000) 
---[ end trace 0000000000000000 ]---


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