================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x103c/0x10a0 drivers/hid/hid-mcp2221.c:957 Read of size 1 at addr ffff888136937fff by task syz.1.2628/14942 CPU: 1 UID: 0 PID: 14942 Comm: syz.1.2628 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __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/0x1d0 mm/kasan/report.c:595 mcp2221_raw_event+0x103c/0x10a0 drivers/hid/hid-mcp2221.c:957 __hid_input_report.constprop.0+0x314/0x460 drivers/hid/hid-core.c:2147 hid_irq_in+0x52e/0x6b0 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1659 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1743 dummy_timer+0xda1/0x36c0 drivers/usb/gadget/udc/dummy_hcd.c:2005 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x470/0xa00 kernel/time/hrtimer.c:1994 hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2011 handle_softirqs+0x1dd/0x9e0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x160/0x210 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:finish_task_switch.isra.0+0x21a/0xa20 kernel/sched/core.c:5245 Code: 08 3c 03 0f 8e 26 06 00 00 c7 83 00 0d 00 00 00 00 00 00 48 8d 7b 48 e8 14 41 ec 05 e8 6f e1 36 00 fb 49 8d bc 24 e8 15 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 RSP: 0018:ffffc900059379c8 EFLAGS: 00000206 RAX: 0000000000000b99 RBX: ffff8881f5739680 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff890c8516 RDI: ffff88811a7b15e8 RBP: ffffc90005937a08 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88811a7b0000 R13: ffff88810d3a9dc0 R14: 0000000000000000 R15: ffff8881f573a380 context_switch kernel/sched/core.c:5391 [inline] __schedule+0x1140/0x47e0 kernel/sched/core.c:7189 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7370 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 class_preempt_destructor include/linux/preempt.h:468 [inline] try_to_wake_up+0x9b1/0x1450 kernel/sched/core.c:4154 wake_up_process kernel/sched/core.c:4434 [inline] wake_up_q+0xa1/0x130 kernel/sched/core.c:1158 futex_wake+0x460/0x530 kernel/futex/waitwake.c:198 do_futex+0x32b/0x350 kernel/futex/syscalls.c:135 __do_sys_futex kernel/futex/syscalls.c:207 [inline] __se_sys_futex kernel/futex/syscalls.c:188 [inline] __x64_sys_futex+0x34f/0x4d0 kernel/futex/syscalls.c:188 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f081275ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffef757568 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f081275ce59 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f08129d5fa8 RBP: 0000000000001e43 R08: 0000000000000005 R09: 0000000000000000 R10: 00007f08129d5fa0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f08129d5fac R14: 00007f08129d5fa8 R15: 00007f08129d5fa0 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x136937 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 0x440dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO|__GFP_COMP), pid 2977, tgid 2977 (syz-executor), ts 280421330788, free_ts 282650085948 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0xf34/0x3a90 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x273/0x28a0 mm/page_alloc.c:5226 alloc_pages_mpol+0xe8/0x410 mm/mempolicy.c:2490 alloc_pages_noprof+0x1a/0x160 mm/mempolicy.c:2581 pagetable_alloc_noprof include/linux/mm.h:3651 [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/0x380 mm/memory.c:453 copy_pte_range mm/memory.c:1237 [inline] copy_pmd_range mm/memory.c:1392 [inline] copy_pud_range mm/memory.c:1429 [inline] copy_p4d_range mm/memory.c:1453 [inline] copy_page_range+0x2d02/0x5740 mm/memory.c:1539 dup_mmap+0xcb9/0x1f30 mm/mmap.c:1840 dup_mm kernel/fork.c:1534 [inline] copy_mm kernel/fork.c:1586 [inline] copy_process+0x4928/0x7c70 kernel/fork.c:2264 kernel_clone+0x12e/0x9c0 kernel/fork.c:2721 __do_sys_clone+0xd9/0x120 kernel/fork.c:2862 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5210 tgid 5210 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0x692/0xf10 mm/page_alloc.c:2943 __pagetable_free include/linux/mm.h:3661 [inline] pagetable_free include/linux/mm.h:3685 [inline] pagetable_dtor_free include/linux/mm.h:3784 [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+0x1dd/0x9e0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x160/0x210 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 Memory state around the buggy address: ffff888136937e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888136937f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888136937f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888136938000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888136938080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 08 3c 03 or %bh,(%rbx,%rax,1) 3: 0f 8e 26 06 00 00 jle 0x62f 9: c7 83 00 0d 00 00 00 movl $0x0,0xd00(%rbx) 10: 00 00 00 13: 48 8d 7b 48 lea 0x48(%rbx),%rdi 17: e8 14 41 ec 05 call 0x5ec4130 1c: e8 6f e1 36 00 call 0x36e190 21: fb sti 22: 49 8d bc 24 e8 15 00 lea 0x15e8(%r12),%rdi 29: 00 * 2a: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax <-- trapping instruction 31: fc ff df 34: 48 89 fa mov %rdi,%rdx 37: 48 c1 ea 03 shr $0x3,%rdx 3b: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax 3f: 84 .byte 0x84