================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x10b0/0x12a0 drivers/hid/hid-mcp2221.c:964 Read of size 1 at addr ffff88804debffff by task syz.0.1583/19757 CPU: 1 UID: 0 PID: 19757 Comm: syz.0.1583 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 mcp2221_raw_event+0x10b0/0x12a0 drivers/hid/hid-mcp2221.c:964 __hid_input_report+0x41c/0x580 drivers/hid/hid-core.c:2161 hid_irq_in+0x492/0x710 drivers/hid/usbhid/hid-core.c:287 __usb_hcd_giveback_urb+0x374/0x530 drivers/usb/core/hcd.c:1657 dummy_timer+0xac3/0x4b40 drivers/usb/gadget/udc/dummy_hcd.c:2005 __run_hrtimer kernel/time/hrtimer.c:2032 [inline] __hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2096 hrtimer_run_softirq+0x17a/0x240 kernel/time/hrtimer.c:2113 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 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:179 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:198 Code: f7 e8 ad 6c d1 f5 f7 c3 00 02 00 00 74 05 e8 10 51 fd f5 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 b4 82 c2 f5 65 8b 05 ad 12 9b 07 85 c0 74 18 5b 41 5e e9 91 48 RSP: 0018:ffffc900067f7948 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000246 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8e229c3f RDI: 0000000000000001 RBP: 0000000000000001 R08: ffffffff90576ff7 R09: 1ffffffff20aedfe R10: dffffc0000000000 R11: fffffbfff20aedff R12: ffff888054246d20 R13: 1ffff110042e4818 R14: ffff888021724000 R15: dffffc0000000000 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] dummy_queue+0x6c8/0x8b0 drivers/usb/gadget/udc/dummy_hcd.c:749 usb_ep_queue+0xf1/0x3c0 drivers/usb/gadget/udc/core.c:303 raw_process_ep_io+0x5e4/0xd80 drivers/usb/gadget/legacy/raw_gadget.c:1114 raw_ioctl_ep_write drivers/usb/gadget/legacy/raw_gadget.c:1153 [inline] raw_ioctl+0x251c/0x41c0 drivers/usb/gadget/legacy/raw_gadget.c:1325 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1f7859daeb Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007f1f79510f60 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f1f7859daeb RDX: 00007f1f79510fe0 RSI: 0000000040085507 RDI: 0000000000000005 RBP: 0000000000000005 R08: 00007f1f78950320 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000246 R12: 00002000000006c0 R13: 0000000000000000 R14: 00007f1f78825fa0 R15: 00007f1f7894fa48 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4debf flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 ffffea000137af88 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 5, migratetype Unmovable, gfp_mask 0x152c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 17582, tgid 17581 (syz.4.1404), ts 468455481657, free_ts 468498327977 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_pages_mpol+0x212/0x380 mm/mempolicy.c:2490 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline] alloc_pages_noprof+0xac/0x2a0 mm/mempolicy.c:2581 folio_alloc_noprof+0x1e/0x30 mm/mempolicy.c:2591 filemap_alloc_folio_noprof+0x111/0x470 mm/filemap.c:1013 ractl_alloc_folio mm/readahead.c:200 [inline] ra_alloc_folio mm/readahead.c:463 [inline] page_cache_ra_order+0x569/0xee0 mm/readahead.c:535 do_async_mmap_readahead mm/filemap.c:3469 [inline] filemap_fault+0x738/0x13b0 mm/filemap.c:3568 __do_fault+0x138/0x2a0 mm/memory.c:5425 do_read_fault mm/memory.c:5860 [inline] do_fault mm/memory.c:5994 [inline] do_pte_missing+0x2215/0x34b0 mm/memory.c:4566 handle_pte_fault mm/memory.c:6379 [inline] __handle_mm_fault mm/memory.c:6517 [inline] handle_mm_fault+0x1b36/0x3080 mm/memory.c:6686 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x1678/0x2720 mm/gup.c:1428 populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860 __mm_populate+0x25f/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:4171 [inline] vm_mmap_pgoff+0x353/0x4e0 mm/util.c:586 page last free pid 17589 tgid 17581 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] free_unref_folios+0xd84/0x14a0 mm/page_alloc.c:3011 shrink_folio_list+0x4b16/0x5330 mm/vmscan.c:1582 reclaim_folio_list+0x100/0x430 mm/vmscan.c:2171 reclaim_pages+0x452/0x530 mm/vmscan.c:2208 madvise_cold_or_pageout_pte_range+0x1be5/0x22b0 mm/madvise.c:563 walk_pmd_range mm/pagewalk.c:148 [inline] walk_pud_range mm/pagewalk.c:239 [inline] walk_p4d_range mm/pagewalk.c:280 [inline] walk_pgd_range+0x100f/0x1e40 mm/pagewalk.c:321 __walk_page_range+0x16d/0x720 mm/pagewalk.c:429 walk_page_range_vma_unsafe+0x309/0x410 mm/pagewalk.c:733 madvise_pageout_page_range mm/madvise.c:622 [inline] madvise_pageout mm/madvise.c:647 [inline] madvise_vma_behavior+0x28cd/0x42e0 mm/madvise.c:1358 madvise_walk_vmas+0x576/0xb00 mm/madvise.c:1713 madvise_do_behavior+0x385/0x540 mm/madvise.c:1908 do_madvise+0x327/0x3a0 mm/madvise.c:2006 __do_sys_madvise mm/madvise.c:2015 [inline] __se_sys_madvise mm/madvise.c:2013 [inline] __x64_sys_madvise+0xa6/0xc0 mm/madvise.c:2013 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88804debfe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804debff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88804debff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88804dec0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88804dec0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: f7 e8 imul %eax 2: ad lods %ds:(%rsi),%eax 3: 6c insb (%dx),%es:(%rdi) 4: d1 f5 shl $1,%ebp 6: f7 c3 00 02 00 00 test $0x200,%ebx c: 74 05 je 0x13 e: e8 10 51 fd f5 call 0xf5fd5123 13: 9c pushf 14: 58 pop %rax 15: a9 00 02 00 00 test $0x200,%eax 1a: 75 27 jne 0x43 1c: f7 c3 00 02 00 00 test $0x200,%ebx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 b4 82 c2 f5 call 0xf5c282e3 <-- trapping instruction 2f: 65 8b 05 ad 12 9b 07 mov %gs:0x79b12ad(%rip),%eax # 0x79b12e3 36: 85 c0 test %eax,%eax 38: 74 18 je 0x52 3a: 5b pop %rbx 3b: 41 5e pop %r14 3d: e9 .byte 0xe9 3e: 91 xchg %eax,%ecx 3f: 48 rex.W