==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0xf94/0x1030 drivers/hid/hid-mcp2221.c:944
Read of size 1 at addr ffff888056783fff by task sed/6359

CPU: 0 UID: 0 PID: 6359 Comm: sed Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 mcp2221_raw_event+0xf94/0x1030 drivers/hid/hid-mcp2221.c:944
 __hid_input_report.constprop.0+0x311/0x450 drivers/hid/hid-core.c:2130
 hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:286
 __usb_hcd_giveback_urb+0x38b/0x610 drivers/usb/core/hcd.c:1661
 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1745
 dummy_timer+0x1814/0x3a30 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+0x216/0x8e0 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:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: a9 3e 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 52 84 13 0f 0f 82 74 02 00 00 8b 35 0a b6 13 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 a9 a8 3e 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0000:ffffc9000c1afa60 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffff8880b8433340 RCX: ffffffff93e31c00
RDX: 0000000000000000 RSI: ffffffff8de2ace0 RDI: ffffffff8c162900
RBP: 0000000000000000 R08: 65e71314f7a92863 R09: 0000000000000001
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 local_lock_acquire include/linux/local_lock_internal.h:38 [inline]
 __folio_batch_add_and_move+0x6b3/0xc90 mm/swap.c:192
 folio_add_lru_vma+0xb0/0x100 mm/swap.c:529
 wp_page_copy mm/memory.c:3620 [inline]
 do_wp_page+0x16c7/0x4f00 mm/memory.c:4013
 handle_pte_fault mm/memory.c:6068 [inline]
 __handle_mm_fault+0x1b2d/0x2a50 mm/memory.c:6195
 handle_mm_fault+0x589/0xd10 mm/memory.c:6364
 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f28ede9f8ec
Code: 1f 80 00 00 00 00 48 8b 31 8b 51 08 4c 01 fe 48 83 fa 26 74 0a 48 83 fa 08 0f 85 ef 3c ff ff 48 8b 51 10 48 83 c1 18 4c 01 fa <48> 89 16 48 39 d9 72 d4 4d 8b 9a 08 02 00 00 4d 85 db 0f 84 ec 0b
RSP: 002b:00007fff39db65e0 EFLAGS: 00010206
RAX: 00007f28eddc7cd0 RBX: 00007f28eddd1280 RCX: 00007f28eddcdd40
RDX: 00007f28eddd7a00 RSI: 00007f28ede840f0 RDI: 00007f28eddd54c8
RBP: 00007fff39db6700 R08: 00007f28eddd2f90 R09: 00007f28eddd54c8
R10: 00007f28ede880c0 R11: 0000000000000000 R12: 00007fff39db6690
R13: 00007fff39db6690 R14: 00007f28ede880c0 R15: 00007f28eddc6000
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56783
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 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 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 13, tgid 13 (kworker/u8:1), ts 67793357079, free_ts 81869054325
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab mm/slub.c:2655 [inline]
 new_slab+0x247/0x330 mm/slub.c:2709
 ___slab_alloc+0xcf2/0x1740 mm/slub.c:3891
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 kmem_cache_alloc_node_noprof+0xf5/0x3b0 mm/slub.c:4281
 kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:578
 __alloc_skb+0x166/0x380 net/core/skbuff.c:669
 alloc_skb include/linux/skbuff.h:1336 [inline]
 nlmsg_new include/net/netlink.h:1055 [inline]
 inet6_rt_notify+0x1e0/0x4b0 net/ipv6/route.c:6347
 fib6_add_rt2node+0x24ba/0x3670 net/ipv6/ip6_fib.c:1275
 fib6_add+0x628/0x1d90 net/ipv6/ip6_fib.c:1528
 __ip6_ins_rt net/ipv6/route.c:1351 [inline]
 ip6_ins_rt+0xb5/0x110 net/ipv6/route.c:1361
 __ipv6_ifa_notify+0xa73/0xd60 net/ipv6/addrconf.c:6283
 ipv6_ifa_notify net/ipv6/addrconf.c:6322 [inline]
 addrconf_dad_completed+0x19a/0x10d0 net/ipv6/addrconf.c:4320
page last free pid 5866 tgid 5866 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895
 discard_slab mm/slub.c:2753 [inline]
 __put_partials+0x165/0x1c0 mm/slub.c:3218
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:340
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_node_noprof+0x1d5/0x3b0 mm/slub.c:4281
 __alloc_skb+0x2b2/0x380 net/core/skbuff.c:659
 alloc_skb include/linux/skbuff.h:1336 [inline]
 alloc_skb_with_frags+0xe0/0x860 net/core/skbuff.c:6665
 sock_alloc_send_pskb+0x7fb/0x990 net/core/sock.c:2980
 unix_dgram_sendmsg+0x3e9/0x17f0 net/unix/af_unix.c:2153
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 sock_write_iter+0x4ff/0x5b0 net/socket.c:1179
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d0/0x11d0 fs/read_write.c:686
 ksys_write+0x1f8/0x250 fs/read_write.c:738
 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:
 ffff888056783e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888056783f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888056783f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff888056784000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888056784080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	3e 12 83 f8 07 0f 87 	ds adc -0x78f0f808(%rbx),%al
   7:	bc 02 00 00 89       	mov    $0x89000002,%esp
   c:	c0 48 0f a3          	rorb   $0xa3,0xf(%rax)
  10:	05 52 84 13 0f       	add    $0xf138452,%eax
  15:	0f 82 74 02 00 00    	jb     0x28f
  1b:	8b 35 0a b6 13 0f    	mov    0xf13b60a(%rip),%esi        # 0xf13b62b
  21:	85 f6                	test   %esi,%esi
  23:	0f 85 8d 00 00 00    	jne    0xb6
* 29:	48 8b 44 24 30       	mov    0x30(%rsp),%rax <-- trapping instruction
  2e:	65 48 2b 05 a9 a8 3e 	sub    %gs:0x123ea8a9(%rip),%rax        # 0x123ea8df
  35:	12
  36:	0f 85 c7 02 00 00    	jne    0x303
  3c:	48                   	rex.W
  3d:	83                   	.byte 0x83
  3e:	c4                   	.byte 0xc4