==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0xf94/0x1030 drivers/hid/hid-mcp2221.c:854
Read of size 1 at addr ffff8880559d3fff by task syz.1.509/7951

CPU: 0 UID: 0 PID: 7951 Comm: syz.1.509 Not tainted 6.16.0-rc6-syzkaller-00002-g155a3c003e55 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x610 mm/kasan/report.c:480
 kasan_report+0xe0/0x110 mm/kasan/report.c:593
 mcp2221_raw_event+0xf94/0x1030 drivers/hid/hid-mcp2221.c:854
 __hid_input_report.constprop.0+0x311/0x450 drivers/hid/hid-core.c:2117
 hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:286
 __usb_hcd_giveback_urb+0x38d/0x6e0 drivers/usb/core/hcd.c:1650
 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1734
 dummy_timer+0x180e/0x3a20 drivers/usb/gadget/udc/dummy_hcd.c:1995
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842
 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:finish_task_switch.isra.0+0x22a/0xc10 kernel/sched/core.c:5265
Code: fb 09 00 00 44 8b 05 09 cc 1f 0f 45 85 c0 0f 85 be 01 00 00 4c 89 e7 e8 a4 f6 ff ff e8 df d5 39 00 fb 65 48 8b 1d be e2 46 12 <48> 8d bb 18 16 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffc90003d0f4b8 EFLAGS: 00000202
RAX: 000000000000603b RBX: ffff88802d0b4880 RCX: ffffffff81c3c22f
RDX: 0000000000000000 RSI: ffffffff8de32e47 RDI: ffffffff8c158f60
RBP: ffffc90003d0f500 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90a98757 R11: 0000000000000001 R12: ffff8880b843a2c0
R13: ffff888027de4880 R14: 0000000000000001 R15: ffff8880b843b130
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0x1172/0x5de0 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6879
 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
 unix_wait_for_peer+0x245/0x280 net/unix/af_unix.c:1596
 unix_dgram_sendmsg+0x16bf/0x1840 net/unix/af_unix.c:2199
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg net/socket.c:727 [inline]
 ____sys_sendmsg+0xa98/0xc70 net/socket.c:2566
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2620
 __sys_sendmmsg+0x200/0x420 net/socket.c:2709
 __do_sys_sendmmsg net/socket.c:2736 [inline]
 __se_sys_sendmmsg net/socket.c:2733 [inline]
 __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2733
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd1ca38e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd1cb28e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fd1ca5b5fa0 RCX: 00007fd1ca38e929
RDX: 0000000000000651 RSI: 0000200000000000 RDI: 0000000000000004
RBP: 00007fd1ca410b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd1ca5b5fa0 R15: 00007ffc7c02f6d8
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x28 pfn:0x559d3
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000028 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 6361, tgid 6361 (udevd), ts 223792997369, free_ts 224931676549
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_pages_noprof mm/mempolicy.c:2510 [inline]
 folio_alloc_noprof+0x20/0x2d0 mm/mempolicy.c:2520
 filemap_alloc_folio_noprof+0x3a1/0x470 mm/filemap.c:1007
 ractl_alloc_folio mm/readahead.c:186 [inline]
 page_cache_ra_unbounded+0x2df/0x7d0 mm/readahead.c:270
 do_page_cache_ra mm/readahead.c:327 [inline]
 force_page_cache_ra+0x246/0x340 mm/readahead.c:356
 page_cache_sync_ra+0x110/0x9c0 mm/readahead.c:575
 filemap_get_pages+0xb62/0x1c20 mm/filemap.c:2602
 filemap_read+0x3d2/0xe40 mm/filemap.c:2711
 blkdev_read_iter+0x1ac/0x500 block/fops.c:833
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x8bf/0xc60 fs/read_write.c:572
 ksys_read+0x12a/0x250 fs/read_write.c:715
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 6361 tgid 6361 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 free_unref_folios+0xa65/0x1800 mm/page_alloc.c:2763
 folios_put_refs+0x56f/0x740 mm/swap.c:992
 folio_batch_release include/linux/pagevec.h:101 [inline]
 truncate_inode_pages_range+0x311/0xe50 mm/truncate.c:383
 kill_bdev block/bdev.c:91 [inline]
 blkdev_flush_mapping+0xfb/0x290 block/bdev.c:712
 blkdev_put_whole+0xc4/0xf0 block/bdev.c:719
 bdev_release+0x47e/0x6d0 block/bdev.c:1144
 blkdev_release+0x15/0x20 block/fops.c:684
 __fput+0x3ff/0xb70 fs/file_table.c:465
 fput_close_sync+0x118/0x260 fs/file_table.c:570
 __do_sys_close fs/open.c:1589 [inline]
 __se_sys_close fs/open.c:1574 [inline]
 __x64_sys_close+0x8b/0x120 fs/open.c:1574
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8880559d3e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880559d3f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8880559d3f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff8880559d4000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880559d4080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	00 00                	add    %al,(%rax)
   2:	44 8b 05 09 cc 1f 0f 	mov    0xf1fcc09(%rip),%r8d        # 0xf1fcc12
   9:	45 85 c0             	test   %r8d,%r8d
   c:	0f 85 be 01 00 00    	jne    0x1d0
  12:	4c 89 e7             	mov    %r12,%rdi
  15:	e8 a4 f6 ff ff       	call   0xfffff6be
  1a:	e8 df d5 39 00       	call   0x39d5fe
  1f:	fb                   	sti
  20:	65 48 8b 1d be e2 46 	mov    %gs:0x1246e2be(%rip),%rbx        # 0x1246e2e6
  27:	12
* 28:	48 8d bb 18 16 00 00 	lea    0x1618(%rbx),%rdi <-- trapping instruction
  2f:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  36:	fc ff df
  39:	48 89 fa             	mov    %rdi,%rdx
  3c:	48                   	rex.W
  3d:	c1                   	.byte 0xc1