==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0xf94/0x1030 drivers/hid/hid-mcp2221.c:854
Read of size 1 at addr ffff8881157dffff by task udevd/5194

CPU: 1 UID: 0 PID: 5194 Comm: udevd Not tainted 6.16.0-rc2-syzkaller-00053-gcf16f408364e #0 PREEMPT(voluntary) 
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:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 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+0x202/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842
 handle_softirqs+0x205/0x8d0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xfa/0x160 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+0x90/0xb0 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:5875
Code: 46 11 0b 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 f2 57 20 09 0f 82 74 02 00 00 8b 35 1a 66 20 09 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 09 46 11 0b 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc9000452f7d0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff890c7d80 RCX: 0000000089b5da51
RDX: 0000000000000000 RSI: ffffffff88ae3146 RDI: ffffffff8768fc40
RBP: 0000000000000002 R08: 1f84128b7b49e189 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 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+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x37/0x50 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x2a0/0x470 mm/slub.c:4745
 ep_unregister_pollwait fs/eventpoll.c:691 [inline]
 __ep_remove+0x11d/0xa70 fs/eventpoll.c:843
 ep_remove_safe+0x1a/0x40 fs/eventpoll.c:894
 do_epoll_ctl+0xeec/0x35b0 fs/eventpoll.c:2421
 __do_sys_epoll_ctl fs/eventpoll.c:2462 [inline]
 __se_sys_epoll_ctl fs/eventpoll.c:2453 [inline]
 __x64_sys_epoll_ctl+0x15c/0x1e0 fs/eventpoll.c:2453
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe18498c85a
Code: 48 8b 0d a1 f5 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 e9 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 6e f5 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffda37b9538 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9
RAX: ffffffffffffffda RBX: 00007ffda37b95dc RCX: 00007fe18498c85a
RDX: 0000000000000008 RSI: 0000000000000002 RDI: 0000000000000009
RBP: 00007ffda37b95d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00005636df82dc90
R13: 0000000000000001 R14: 0000000000000002 R15: 00007ffda37b9590
 </TASK>

Allocated by task 15943:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x14f/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2905 [inline]
 do_sys_openat2+0xb8/0x1d0 fs/open.c:1431
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 15943:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x37/0x50 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x2a0/0x470 mm/slub.c:4745
 putname+0x154/0x1a0 fs/namei.c:297
 do_sys_openat2+0x152/0x1d0 fs/open.c:1445
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8881157de600
 which belongs to the cache names_cache of size 4096
The buggy address is located 2559 bytes to the right of
 allocated 4096-byte region [ffff8881157de600, ffff8881157df600)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1157d8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff888100ee0000 ffffea0004e32c00 dead000000000002
raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 0200000000000040 ffff888100ee0000 ffffea0004e32c00 dead000000000002
head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 0200000000000003 ffffea000455f601 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5440, tgid 5440 (udevd), ts 791387338449, free_ts 791232057621
 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+0xf98/0x2ce0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x259/0x21e0 mm/page_alloc.c:4959
 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xda5/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 kmem_cache_alloc_noprof+0x1f9/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2905 [inline]
 do_sys_openat2+0xb8/0x1d0 fs/open.c:1431
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5482 tgid 5482 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x78a/0x1040 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3186
 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+0x4e/0x70 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x14f/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 do_readlinkat+0xb4/0x3a0 fs/stat.c:575
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8881157dfe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881157dff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881157dff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                                ^
 ffff8881157e0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881157e0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
   0:	46 11 0b             	rex.RX adc %r9d,(%rbx)
   3:	83 f8 07             	cmp    $0x7,%eax
   6:	0f 87 bc 02 00 00    	ja     0x2c8
   c:	89 c0                	mov    %eax,%eax
   e:	48 0f a3 05 f2 57 20 	bt     %rax,0x92057f2(%rip)        # 0x9205808
  15:	09
  16:	0f 82 74 02 00 00    	jb     0x290
  1c:	8b 35 1a 66 20 09    	mov    0x920661a(%rip),%esi        # 0x920663c
  22:	85 f6                	test   %esi,%esi
  24:	0f 85 8d 00 00 00    	jne    0xb7
* 2a:	48 8b 44 24 30       	mov    0x30(%rsp),%rax <-- trapping instruction
  2f:	65 48 2b 05 09 46 11 	sub    %gs:0xb114609(%rip),%rax        # 0xb114640
  36:	0b
  37:	0f 85 c7 02 00 00    	jne    0x304
  3d:	48                   	rex.W
  3e:	83                   	.byte 0x83
  3f:	c4                   	.byte 0xc4