==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:948
Read of size 1 at addr ffff888062633fff by task syz.0.1072/9539

CPU: 0 UID: 0 PID: 9539 Comm: syz.0.1072 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:948
 __hid_input_report drivers/hid/hid-core.c:2139 [inline]
 hid_input_report+0x41d/0x580 drivers/hid/hid-core.c:2166
 hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286
 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1661
 dummy_timer+0x85f/0x45b0 drivers/usb/gadget/udc/dummy_hcd.c:1995
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841
 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858
 handle_softirqs+0x286/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5122
Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 1f 51 c5 09 e8 6a d7 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 58 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc90003947c38 EFLAGS: 00000282
RAX: 086eda318b76c100 RBX: 0000000000000000 RCX: 086eda318b76c100
RDX: 0000000000000000 RSI: ffffffff8d779c30 RDI: ffffffff8bbf2040
RBP: ffffc90003947c90 R08: ffffffff8f7d5a77 R09: 1ffffffff1efab4e
R10: dffffc0000000000 R11: fffffbfff1efab4f R12: ffff888027409e40
R13: dffffc0000000000 R14: ffff88802a8a9e40 R15: ffff8880b863ab98
 context_switch kernel/sched/core.c:5257 [inline]
 __schedule+0x17cc/0x4d60 kernel/sched/core.c:6862
 __schedule_loop kernel/sched/core.c:6944 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6959
 exit_to_user_mode_loop kernel/entry/common.c:31 [inline]
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 irqentry_exit_to_user_mode+0x5d/0x110 kernel/entry/common.c:73
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0033:0x7f51b1c68234
Code: 84 00 00 00 00 00 48 8b 4b 08 48 83 c3 08 48 39 d1 72 f3 48 83 e8 08 48 39 f2 73 17 66 2e 0f 1f 84 00 00 00 00 00 48 8b 70 f8 <48> 83 e8 08 48 39 f2 72 f3 48 39 c3 73 3e 48 89 33 48 83 c3 08 48
RSP: 002b:00007fffe1929780 EFLAGS: 00000283
RAX: 00007f51b1a18a78 RBX: 00007f51b18bad18 RCX: ffffffff82627962
RDX: ffffffff826251e7 RSI: ffffffff84c3f37a RDI: 00007f51b1aa19d8
RBP: 00007f51b1876ca0 R08: 00007f51b198c338 R09: 00007f51b1fd2000
R10: 00007f51b17ff008 R11: 0000000000000000 R12: 00007f51b1876c98
R13: 0000000000000021 R14: 00007fffe19298d8 R15: 00007f51b17ff008
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xb1cd9 pfn:0x62633
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: 00000000000b1cd9 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x152c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 8656, tgid 8655 (syz.3.842), ts 221669996622, free_ts 222151364450
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3920
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5214
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2479
 alloc_frozen_pages_noprof mm/mempolicy.c:2550 [inline]
 alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2570
 folio_alloc_noprof+0x1e/0x30 mm/mempolicy.c:2580
 filemap_alloc_folio_noprof+0x112/0x490 mm/filemap.c:1025
 ractl_alloc_folio mm/readahead.c:189 [inline]
 ra_alloc_folio mm/readahead.c:446 [inline]
 page_cache_ra_order+0x55d/0xe70 mm/readahead.c:512
 do_sync_mmap_readahead+0x66a/0x870 mm/filemap.c:3354
 filemap_fault+0x6bc/0x12b0 mm/filemap.c:3503
 __do_fault+0x138/0x390 mm/memory.c:5324
 do_read_fault mm/memory.c:5751 [inline]
 do_fault mm/memory.c:5885 [inline]
 do_pte_missing mm/memory.c:4405 [inline]
 handle_pte_fault mm/memory.c:6230 [inline]
 __handle_mm_fault+0x35dc/0x5440 mm/memory.c:6372
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6541
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x1650/0x29f0 mm/gup.c:1428
 populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1860
 __mm_populate+0x24c/0x380 mm/gup.c:1963
page last free pid 8656 tgid 8655 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 free_unref_folios+0xd22/0x1460 mm/page_alloc.c:3005
 folios_put_refs+0x584/0x670 mm/swap.c:1002
 folio_batch_release include/linux/pagevec.h:101 [inline]
 truncate_inode_pages_range+0x346/0xda0 mm/truncate.c:385
 kill_bdev block/bdev.c:91 [inline]
 blkdev_flush_mapping+0x108/0x270 block/bdev.c:712
 blkdev_put_whole block/bdev.c:719 [inline]
 bdev_release+0x417/0x650 block/bdev.c:1144
 blkdev_release+0x15/0x20 block/fops.c:709
 __fput+0x44c/0xa70 fs/file_table.c:468
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x2300 kernel/exit.c:966
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888062633e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888062633f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888062633f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff888062634000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888062634080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
   0:	0f 84 3c 01 00 00    	je     0x142
   6:	48 85 db             	test   %rbx,%rbx
   9:	0f 85 63 01 00 00    	jne    0x172
   f:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  14:	4c 8b 75 d0          	mov    -0x30(%rbp),%r14
  18:	4c 89 e7             	mov    %r12,%rdi
  1b:	e8 1f 51 c5 09       	call   0x9c5513f
  20:	e8 6a d7 36 00       	call   0x36d78f
  25:	fb                   	sti
  26:	4c 8b 65 c0          	mov    -0x40(%rbp),%r12
* 2a:	49 8d bc 24 58 16 00 	lea    0x1658(%r12),%rdi <-- trapping instruction
  31:	00
  32:	48 89 f8             	mov    %rdi,%rax
  35:	48 c1 e8 03          	shr    $0x3,%rax
  39:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
  3e:	84 c0                	test   %al,%al