==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:948
Read of size 1 at addr ffff888055503fff by task udevd/5992

CPU: 0 UID: 0 PID: 5992 Comm: udevd 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_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:2130 [inline]
 hid_input_report+0x40a/0x520 drivers/hid/hid-core.c:2157
 hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286
 __usb_hcd_giveback_urb+0x373/0x540 drivers/usb/core/hcd.c:1661
 dummy_timer+0x862/0x4550 drivers/usb/gadget/udc/dummy_hcd.c:1995
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1842
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 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+0xa6/0xc0 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+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 8b 21 03 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90004767618 EFLAGS: 00000206
RAX: 16bc914c05c82a00 RBX: 0000000000000000 RCX: 16bc914c05c82a00
RDX: 0000000000000000 RSI: ffffffff8dba7f2b RDI: ffffffff8be33880
RBP: ffffffff8172c195 R08: 0000000000000000 R09: ffffffff8172c195
R10: ffffc900047677d8 R11: ffffffff81ac3ad0 R12: 0000000000000002
R13: ffffffff8e139f20 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
 discard_slab mm/slub.c:2753 [inline]
 __put_partials+0x156/0x1a0 mm/slub.c:3218
 put_cpu_partial+0x17c/0x250 mm/slub.c:3293
 __slab_free+0x2d5/0x3c0 mm/slub.c:4550
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 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_noprof+0x1c1/0x3c0 mm/slub.c:4236
 getname_flags+0xb8/0x540 fs/namei.c:146
 getname include/linux/fs.h:2918 [inline]
 getname_maybe_null include/linux/fs.h:2925 [inline]
 vfs_fstatat+0x43/0x170 fs/stat.c:370
 __do_sys_newfstatat fs/stat.c:542 [inline]
 __se_sys_newfstatat fs/stat.c:536 [inline]
 __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3815b11b0a
Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7
RSP: 002b:00007fff42311278 EFLAGS: 00000202 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 000055cf62b4dbd1 RCX: 00007f3815b11b0a
RDX: 00007fff42311280 RSI: 00007fff42311310 RDI: 00000000ffffff9c
RBP: 000055cf62b35830 R08: 000055cf62b4dbd1 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000202 R12: 000055cf62b35920
R13: 00007fff42311310 R14: 000055cf62b2164c R15: 000055cf2ba76bcc
 </TASK>

Allocated by task 6009:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:330 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356
 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+0x1bb/0x3c0 mm/slub.c:4281
 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:578
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:669
 alloc_skb include/linux/skbuff.h:1336 [inline]
 nlmsg_new include/net/netlink.h:1055 [inline]
 inet6_netconf_notify_devconf+0x10f/0x1d0 net/ipv6/addrconf.c:593
 __addrconf_sysctl_register+0x451/0x4c0 net/ipv6/addrconf.c:7332
 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7369
 ipv6_add_dev+0xd46/0x1370 net/ipv6/addrconf.c:460
 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3650
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
 call_netdevice_notifiers net/core/dev.c:2281 [inline]
 register_netdevice+0x1608/0x1ae0 net/core/dev.c:11244
 tun_set_iff+0x844/0xef0 drivers/net/tun.c:2804
 __tun_chr_ioctl+0x788/0x1df0 drivers/net/tun.c:3085
 __do_compat_sys_ioctl fs/ioctl.c:696 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:639 [inline]
 __ia32_compat_sys_ioctl+0x540/0x840 fs/ioctl.c:639
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Freed by task 6009:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:243 [inline]
 __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2417 [inline]
 slab_free mm/slub.c:4680 [inline]
 kmem_cache_free+0x18f/0x400 mm/slub.c:4782
 skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1086
 skb_release_all net/core/skbuff.c:1151 [inline]
 __kfree_skb net/core/skbuff.c:1165 [inline]
 consume_skb+0x9e/0xf0 net/core/skbuff.c:1397
 netlink_broadcast_filtered+0x1188/0x12c0 net/netlink/af_netlink.c:1537
 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
 nlmsg_multicast include/net/netlink.h:1184 [inline]
 nlmsg_notify+0xf0/0x1a0 net/netlink/af_netlink.c:2595
 __addrconf_sysctl_register+0x451/0x4c0 net/ipv6/addrconf.c:7332
 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7369
 ipv6_add_dev+0xd46/0x1370 net/ipv6/addrconf.c:460
 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3650
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
 call_netdevice_notifiers net/core/dev.c:2281 [inline]
 register_netdevice+0x1608/0x1ae0 net/core/dev.c:11244
 tun_set_iff+0x844/0xef0 drivers/net/tun.c:2804
 __tun_chr_ioctl+0x788/0x1df0 drivers/net/tun.c:3085
 __do_compat_sys_ioctl fs/ioctl.c:696 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:639 [inline]
 __ia32_compat_sys_ioctl+0x540/0x840 fs/ioctl.c:639
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

The buggy address belongs to the object at ffff888055503a80
 which belongs to the cache skbuff_small_head of size 704
The buggy address is located 703 bytes to the right of
 allocated 704-byte region [ffff888055503a80, ffff888055503d40)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55500
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801e2f8b40 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801e2f8b40 dead000000000122 0000000000000000
head: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0001554001 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5992, tgid 5992 (udevd), ts 111318167346, free_ts 32476181789
 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+0x21e4/0x22c0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2655
 new_slab mm/slub.c:2709 [inline]
 ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
 __slab_alloc mm/slub.c:3981 [inline]
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 kmem_cache_alloc_node_noprof+0x280/0x3c0 mm/slub.c:4281
 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:578
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:669
 skb_copy+0x188/0x800 net/core/skbuff.c:2124
 mac80211_hwsim_tx_frame_no_nl+0xcd3/0x11c0 drivers/net/wireless/virtual/mac80211_hwsim.c:1871
 mac80211_hwsim_tx_frame+0x1b5/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2222
 mac80211_hwsim_beacon_tx+0x3f0/0x860 drivers/net/wireless/virtual/mac80211_hwsim.c:2323
 __iterate_interfaces+0x2a8/0x590 net/mac80211/util.c:761
 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:797
 mac80211_hwsim_beacon+0xbb/0x1c0 drivers/net/wireless/virtual/mac80211_hwsim.c:2353
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
 __free_pages mm/page_alloc.c:5260 [inline]
 free_contig_range+0x1bd/0x4a0 mm/page_alloc.c:7091
 destroy_args+0x69/0x660 mm/debug_vm_pgtable.c:958
 debug_vm_pgtable+0x39f/0x3b0 mm/debug_vm_pgtable.c:1345
 do_one_initcall+0x233/0x820 init/main.c:1269
 do_initcall_level+0x104/0x190 init/main.c:1331
 do_initcalls+0x59/0xa0 init/main.c:1347
 kernel_init_freeable+0x334/0x4b0 init/main.c:1579
 kernel_init+0x1d/0x1d0 init/main.c:1469
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888055503e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888055503f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888055503f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                                ^
 ffff888055504000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888055504080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	9c                   	pushf
   5:	8f 44 24 30          	pop    0x30(%rsp)
   9:	f7 44 24 30 00 02 00 	testl  $0x200,0x30(%rsp)
  10:	00
  11:	0f 85 cd 00 00 00    	jne    0xe4
  17:	f7 44 24 08 00 02 00 	testl  $0x200,0x8(%rsp)
  1e:	00
  1f:	74 01                	je     0x22
  21:	fb                   	sti
  22:	65 48 8b 05 8b 21 03 	mov    %gs:0x1103218b(%rip),%rax        # 0x110321b5
  29:	11
* 2a:	48 3b 44 24 58       	cmp    0x58(%rsp),%rax <-- trapping instruction
  2f:	0f 85 f2 00 00 00    	jne    0x127
  35:	48 83 c4 60          	add    $0x60,%rsp
  39:	5b                   	pop    %rbx
  3a:	41 5c                	pop    %r12
  3c:	41 5d                	pop    %r13
  3e:	41 5e                	pop    %r14