==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948
Read of size 1 at addr ffff88811f403fff by task klogd/2851

CPU: 0 UID: 0 PID: 2851 Comm: klogd Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948
 __hid_input_report.constprop.0+0x314/0x470 drivers/hid/hid-core.c:2139
 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+0x1809/0x3ad0 drivers/usb/gadget/udc/dummy_hcd.c:1995
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858
 handle_softirqs+0x208/0x940 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:_prb_read_valid+0x69/0x890 kernel/printk/printk_ringbuffer.c:2166
Code: c7 44 24 70 b3 8a b5 41 48 c7 44 24 78 e8 b7 da 88 48 c7 84 24 80 00 00 00 60 82 5f 81 c7 00 f1 f1 f1 f1 c7 40 04 f1 f1 04 f2 <c7> 40 08 00 f2 f2 f2 c7 40 0c 00 00 00 f3 c7 40 10 f3 f3 f3 f3 65
RSP: 0018:ffffc9000162fa48 EFLAGS: 00000282
RAX: fffff520002c5f57 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: ffffc9000162fc80 RSI: ffffc9000162fbd0 RDI: ffffffff891dad40
RBP: ffffffff891dad40 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000351 R11: ffff8881178127e8 R12: 1ffff920002c5f57
R13: 00000000000000ae R14: ffffffff891dad40 R15: ffffc9000162fbd0
 prb_read_valid+0x78/0xa0 kernel/printk/printk_ringbuffer.c:2242
 syslog_print+0x3c9/0x620 kernel/printk/printk.c:1626
 do_syslog+0x3dc/0x6c0 kernel/printk/printk.c:1761
 __do_sys_syslog kernel/printk/printk.c:1853 [inline]
 __se_sys_syslog kernel/printk/printk.c:1851 [inline]
 __x64_sys_syslog+0x74/0xb0 kernel/printk/printk.c:1851
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdb0ca41a37
Code: 73 01 c3 48 8b 0d c1 f3 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 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 f3 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffd213d41c8 EFLAGS: 00000206 ORIG_RAX: 0000000000000067
RAX: ffffffffffffffda RBX: 00007fdb0cbe1490 RCX: 00007fdb0ca41a37
RDX: 00000000000003ff RSI: 00007fdb0cbe1490 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000206 R12: 00007fdb0cbe1490
R13: 00007fdb0cbbedfe R14: 00007fdb0cbe14c2 R15: 00007fdb0cbe14c2
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11f403
flags: 0x200000000000000(node=0|zone=2)
raw: 0200000000000000 dead000000000100 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 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL), pid 30178, tgid 30178 (syz-executor), ts 3063369540635, free_ts 3124864046466
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0x1058/0x3cb0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x259/0x21c0 mm/page_alloc.c:5210
 __alloc_pages_noprof mm/page_alloc.c:5244 [inline]
 alloc_pages_bulk_noprof+0x6f5/0x1160 mm/page_alloc.c:5164
 ___alloc_pages_bulk mm/kasan/shadow.c:345 [inline]
 __kasan_populate_vmalloc_do mm/kasan/shadow.c:370 [inline]
 __kasan_populate_vmalloc+0xfb/0x220 mm/kasan/shadow.c:424
 kasan_populate_vmalloc include/linux/kasan.h:579 [inline]
 alloc_vmap_area+0x98d/0x2a50 mm/vmalloc.c:2124
 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3219
 __vmalloc_node_range_noprof+0x247/0x16b0 mm/vmalloc.c:4011
 vmalloc_user_noprof+0x9e/0xe0 mm/vmalloc.c:4205
 kcov_ioctl+0x4c/0x6e0 kernel/kcov.c:716
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5281 tgid 5281 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x795/0x1010 mm/page_alloc.c:2943
 kasan_depopulate_vmalloc_pte+0x5b/0x80 mm/kasan/shadow.c:484
 apply_to_pte_range mm/memory.c:3182 [inline]
 apply_to_pmd_range mm/memory.c:3226 [inline]
 apply_to_pud_range mm/memory.c:3262 [inline]
 apply_to_p4d_range mm/memory.c:3298 [inline]
 __apply_to_page_range+0xac1/0x13f0 mm/memory.c:3334
 __kasan_release_vmalloc+0xd1/0xe0 mm/kasan/shadow.c:602
 kasan_release_vmalloc include/linux/kasan.h:592 [inline]
 kasan_release_vmalloc_node mm/vmalloc.c:2282 [inline]
 purge_vmap_node+0x1ba/0xad0 mm/vmalloc.c:2299
 __purge_vmap_area_lazy+0x9d2/0xc00 mm/vmalloc.c:2389
 drain_vmap_area_work+0x27/0x40 mm/vmalloc.c:2423
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Memory state around the buggy address:
 ffff88811f403e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88811f403f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88811f403f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff88811f404000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88811f404080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
   0:	c7 44 24 70 b3 8a b5 	movl   $0x41b58ab3,0x70(%rsp)
   7:	41
   8:	48 c7 44 24 78 e8 b7 	movq   $0xffffffff88dab7e8,0x78(%rsp)
   f:	da 88
  11:	48 c7 84 24 80 00 00 	movq   $0xffffffff815f8260,0x80(%rsp)
  18:	00 60 82 5f 81
  1d:	c7 00 f1 f1 f1 f1    	movl   $0xf1f1f1f1,(%rax)
  23:	c7 40 04 f1 f1 04 f2 	movl   $0xf204f1f1,0x4(%rax)
* 2a:	c7 40 08 00 f2 f2 f2 	movl   $0xf2f2f200,0x8(%rax) <-- trapping instruction
  31:	c7 40 0c 00 00 00 f3 	movl   $0xf3000000,0xc(%rax)
  38:	c7 40 10 f3 f3 f3 f3 	movl   $0xf3f3f3f3,0x10(%rax)
  3f:	65                   	gs