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BUG: KASAN: use-after-free in mcp2221_raw_event+0x10b0/0x12a0 drivers/hid/hid-mcp2221.c:964
Read of size 1 at addr ffff888037e27fff by task ktimers/0/16

CPU: 0 UID: 0 PID: 16 Comm: ktimers/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 mcp2221_raw_event+0x10b0/0x12a0 drivers/hid/hid-mcp2221.c:964
 __hid_input_report+0x421/0x580 drivers/hid/hid-core.c:2168
 hid_irq_in+0x492/0x710 drivers/hid/usbhid/hid-core.c:287
 __usb_hcd_giveback_urb+0x3b8/0x5f0 drivers/usb/core/hcd.c:1657
 dummy_timer+0xab9/0x4b30 drivers/usb/gadget/udc/dummy_hcd.c:2005
 __run_hrtimer kernel/time/hrtimer.c:2065 [inline]
 __hrtimer_run_queues+0x3eb/0xaf0 kernel/time/hrtimer.c:2122
 hrtimer_run_softirq+0x18f/0x260 kernel/time/hrtimer.c:2139
 handle_softirqs+0x1d9/0x6c0 kernel/softirq.c:626
 __do_softirq kernel/softirq.c:660 [inline]
 run_ktimerd+0x69/0x100 kernel/softirq.c:1155
 smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x37e27
flags: 0x80000000000000(node=0|zone=1)
raw: 0080000000000000 0000000000000000 00000000ffffffff 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5663, tgid 5663 (kworker/u8:5), ts 521982774205
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x264c/0x26c0 mm/page_alloc.c:3955
 __alloc_frozen_pages_noprof+0x222/0x5b0 mm/page_alloc.c:5394
 alloc_slab_page mm/slub.c:3295 [inline]
 allocate_slab+0x7c/0x5e0 mm/slub.c:3410
 new_slab mm/slub.c:3456 [inline]
 refill_objects+0x2d8/0x350 mm/slub.c:7321
 refill_sheaf mm/slub.c:2833 [inline]
 __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4699
 alloc_from_pcs mm/slub.c:4775 [inline]
 slab_alloc_node mm/slub.c:4909 [inline]
 __do_kmalloc_node mm/slub.c:5338 [inline]
 __kmalloc_node_track_caller_noprof+0x616/0x7b0 mm/slub.c:5468
 kmalloc_reserve net/core/skbuff.c:637 [inline]
 __alloc_skb+0x2bd/0x7a0 net/core/skbuff.c:715
 alloc_skb include/linux/skbuff.h:1384 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
 nsim_dev_trap_report_work+0x2b1/0xcb0 drivers/net/netdevsim/dev.c:922
 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379
 process_scheduled_works kernel/workqueue.c:3462 [inline]
 worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page last free pid 5624 tgid 5624 ts 569039578795 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0x1185/0x1270 mm/page_alloc.c:2962
 __slab_free+0x252/0x2a0 mm/slub.c:5738
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4608 [inline]
 slab_alloc_node mm/slub.c:4921 [inline]
 kmem_cache_alloc_node_noprof+0x3f4/0x660 mm/slub.c:4993
 kmalloc_reserve net/core/skbuff.c:615 [inline]
 __alloc_skb+0x276/0x7a0 net/core/skbuff.c:715
 alloc_skb_fclone include/linux/skbuff.h:1434 [inline]
 tcp_stream_alloc_skb+0x3f/0x5c0 net/ipv4/tcp.c:931
 tcp_sendmsg_locked+0x143d/0x55c0 net/ipv4/tcp.c:1256
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1451
 sock_sendmsg_nosec+0x10e/0x180 net/socket.c:811
 __sock_sendmsg net/socket.c:825 [inline]
 sock_write_iter+0x2e4/0x3f0 net/socket.c:1281
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x61e/0xbb0 fs/read_write.c:687
 ksys_write+0x156/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x17b/0x530 arch/x86/entry/syscall_64.c:85
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888037e27e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888037e27f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888037e27f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff888037e28000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888037e28080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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