==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0x110d/0x1140 drivers/hid/hid-mcp2221.c:975
Read of size 1 at addr ffff8881255dffff by task pr/ttyS0/15

CPU: 1 UID: 0 PID: 15 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 mcp2221_raw_event+0x110d/0x1140 drivers/hid/hid-mcp2221.c:975
 __hid_input_report.constprop.0+0x319/0x470 drivers/hid/hid-core.c:2175
 hid_irq_in+0x55d/0x710 drivers/hid/usbhid/hid-core.c:287
 __usb_hcd_giveback_urb+0x38e/0x610 drivers/usb/core/hcd.c:1657
 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
 dummy_timer+0xdaf/0x3820 drivers/usb/gadget/udc/dummy_hcd.c:2023
 __run_hrtimer kernel/time/hrtimer.c:2074 [inline]
 __hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2131
 hrtimer_run_softirq+0x1ca/0x360 kernel/time/hrtimer.c:2148
 handle_softirqs+0x1d9/0x9b0 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0x168/0x210 kernel/softirq.c:758
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:221
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 b6 67 04 fa 48 89 df e8 3e be 04 fa f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 75 02 f7 f9 65 48 83 3d b4 fe 97 05 00 74 16 5b
RSP: 0018:ffffc900000ffcb8 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff944968e0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff892df159 RDI: ffffffff87d2bd80
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 205d373338355420 R12: 1ffff9200001ff9a
R13: ffffffff89ebc480 R14: 0000000000000001 R15: 0000000000000001
 nbcon_emit_one+0x15c/0x2b0 kernel/printk/nbcon.c:1165
 nbcon_kthread_func+0x613/0x7d0 kernel/printk/nbcon.c:1271
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x69f/0xc90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8881255df460 pfn:0x1255df
flags: 0x200000000000000(node=0|zone=2)
raw: 0200000000000000 ffffea00047cb708 ffffea000495bcc8 0000000000000000
raw: ffff8881255df460 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 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3109, tgid 3109 (modprobe), ts 89705281184
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0xf4b/0x3440 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x2d7/0x2f70 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3347 [inline]
 allocate_slab mm/slub.c:3462 [inline]
 new_slab+0xa9/0x6e0 mm/slub.c:3513
 refill_objects+0xe3/0x410 mm/slub.c:7418
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 kmem_cache_alloc_noprof+0x471/0x650 mm/slub.c:5010
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 anon_vma_clone+0x2b3/0xca0 mm/rmap.c:346
 __split_vma+0x750/0x1db0 mm/vma.c:580
 split_vma mm/vma.c:643 [inline]
 vma_modify+0x1252/0x2610 mm/vma.c:1779
 vma_modify_flags+0x25d/0x3e0 mm/vma.c:1799
 mprotect_fixup+0x27a/0xe00 mm/mprotect.c:824
 do_mprotect_pkey+0xa51/0xdd0 mm/mprotect.c:1002
 __do_sys_mprotect mm/mprotect.c:1023 [inline]
 __se_sys_mprotect mm/mprotect.c:1020 [inline]
 __x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:1020
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x119/0x710 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5823 tgid 5823 ts 155017400579 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0x714/0xfc0 mm/page_alloc.c:2962
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:361
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 __kmalloc_cache_noprof+0x273/0x680 mm/slub.c:5559
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 inode_doinit_use_xattr+0x54/0x330 security/selinux/hooks.c:1379
 inode_doinit_with_dentry+0x10fc/0x1340 security/selinux/hooks.c:1574
 selinux_d_instantiate+0x26/0x40 security/selinux/hooks.c:6800
 security_d_instantiate+0x62/0xc0 security/security.c:3703
 d_splice_alias_ops+0xd7/0x15b0 fs/dcache.c:3253
 kernfs_iop_lookup+0x23f/0x2d0 fs/kernfs/dir.c:1288
 lookup_open+0xa79/0x1990 fs/namei.c:4528
 open_last_lookups fs/namei.c:4767 [inline]
 path_openat+0xa2c/0x2440 fs/namei.c:4997
 do_file_open+0x20e/0x430 fs/namei.c:5029
 do_sys_openat2+0x10f/0x1e0 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_sys_openat fs/open.c:1439 [inline]
 __se_sys_openat fs/open.c:1434 [inline]
 __x64_sys_openat+0x12d/0x210 fs/open.c:1434

Memory state around the buggy address:
 ffff8881255dfe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881255dff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881255dff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff8881255e0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881255e0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
   0:	f5                   	cmc
   1:	53                   	push   %rbx
   2:	48 8b 74 24 10       	mov    0x10(%rsp),%rsi
   7:	48 89 fb             	mov    %rdi,%rbx
   a:	48 83 c7 18          	add    $0x18,%rdi
   e:	e8 b6 67 04 fa       	call   0xfa0467c9
  13:	48 89 df             	mov    %rbx,%rdi
  16:	e8 3e be 04 fa       	call   0xfa04be59
  1b:	f7 c5 00 02 00 00    	test   $0x200,%ebp
  21:	75 23                	jne    0x46
  23:	9c                   	pushf
  24:	58                   	pop    %rax
  25:	f6 c4 02             	test   $0x2,%ah
  28:	75 37                	jne    0x61
* 2a:	bf 01 00 00 00       	mov    $0x1,%edi <-- trapping instruction
  2f:	e8 75 02 f7 f9       	call   0xf9f702a9
  34:	65 48 83 3d b4 fe 97 	cmpq   $0x0,%gs:0x597feb4(%rip)        # 0x597fef1
  3b:	05 00
  3d:	74 16                	je     0x55
  3f:	5b                   	pop    %rbx