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BUG: KASAN: use-after-free in mcp2221_raw_event+0x103c/0x10a0 drivers/hid/hid-mcp2221.c:950
Read of size 1 at addr ffff88811f45bfff by task syz-executor/18151

CPU: 0 UID: 0 PID: 18151 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __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+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 mcp2221_raw_event+0x103c/0x10a0 drivers/hid/hid-mcp2221.c:950
 __hid_input_report.constprop.0+0x314/0x460 drivers/hid/hid-core.c:2139
 hid_irq_in+0x52e/0x6b0 drivers/hid/usbhid/hid-core.c:286
 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657
 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
 dummy_timer+0xd85/0x3670 drivers/usb/gadget/udc/dummy_hcd.c:1995
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x50e/0xa70 kernel/time/hrtimer.c:1849
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1866
 handle_softirqs+0x1de/0x9d0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xed/0x150 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+0x42/0xb0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0033:0x7fe7ee4fd383
Code: 48 89 0c 24 29 c7 48 69 ff e8 03 00 00 48 89 7c 24 08 48 89 e7 e8 fd c6 02 00 48 8b 54 24 18 64 48 2b 14 25 28 00 00 00 75 05 <48> 83 c4 28 c3 e8 93 19 00 00 0f 1f 00 48 83 ec 10 48 63 d2 48 63
RSP: 002b:00007fff1cce3080 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00000000000005e8 RCX: 00007fe7ee4b7997
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff1cce30ec R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000001388
R13: 00000000000927c0 R14: 00000000002cef54 R15: 00007fff1cce3140
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88811f45b7c0 pfn:0x11f45b
flags: 0x200000000000000(node=0|zone=2)
page_type: f0(buddy)
raw: 0200000000000000 ffffea00049c9708 ffffea000435cf88 0000000000000000
raw: ffff88811f45b7c0 0000000000000000 00000000f0000000 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 0x440dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO|__GFP_COMP), pid 28286, tgid 28286 (dhcpcd-run-hook), ts 2916500633596, free_ts 2916599764406
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0xf10/0x39f0 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x273/0x2860 mm/page_alloc.c:5250
 alloc_pages_mpol+0xe8/0x410 mm/mempolicy.c:2484
 alloc_frozen_pages_noprof mm/mempolicy.c:2555 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2575
 pagetable_alloc_noprof include/linux/mm.h:3404 [inline]
 __pte_alloc_one_noprof include/asm-generic/pgalloc.h:76 [inline]
 pte_alloc_one+0x1c/0x3d0 arch/x86/mm/pgtable.c:18
 __pte_alloc+0x6d/0x3e0 mm/memory.c:466
 copy_pte_range mm/memory.c:1250 [inline]
 copy_pmd_range mm/memory.c:1405 [inline]
 copy_pud_range mm/memory.c:1442 [inline]
 copy_p4d_range mm/memory.c:1466 [inline]
 copy_page_range+0x1698/0x2760 mm/memory.c:1552
 dup_mmap+0xcb9/0x1f30 mm/mmap.c:1841
 dup_mm kernel/fork.c:1531 [inline]
 copy_mm kernel/fork.c:1583 [inline]
 copy_process+0x424b/0x7820 kernel/fork.c:2223
 kernel_clone+0xfc/0x9a0 kernel/fork.c:2653
 __do_sys_clone+0xd9/0x120 kernel/fork.c:2794
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0x7b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 22 tgid 22 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0x7b1/0xfb0 mm/page_alloc.c:2978
 __pagetable_free include/linux/mm.h:3414 [inline]
 pagetable_free include/linux/mm.h:3438 [inline]
 pagetable_dtor_free include/linux/mm.h:3537 [inline]
 __tlb_remove_table include/asm-generic/tlb.h:221 [inline]
 __tlb_remove_table_free mm/mmu_gather.c:228 [inline]
 tlb_remove_table_rcu+0x2cf/0x380 mm/mmu_gather.c:291
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869
 handle_softirqs+0x1de/0x9d0 kernel/softirq.c:622
 run_ksoftirqd kernel/softirq.c:1063 [inline]
 run_ksoftirqd+0x38/0x60 kernel/softirq.c:1055
 smpboot_thread_fn+0x3d3/0xaa0 kernel/smpboot.c:160
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88811f45be80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88811f45bf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88811f45bf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff88811f45c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88811f45c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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