================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x103c/0x10a0 drivers/hid/hid-mcp2221.c:950 Read of size 1 at addr ffff88810e2abfff by task swapper/0/0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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+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:2140 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+0xda1/0x36c0 drivers/usb/gadget/udc/dummy_hcd.c:2005 __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+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: ce b0 01 e9 53 e8 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 87 1c 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff89407e10 EFLAGS: 00000246 RAX: 000000000022418d RBX: ffffffff8942ea40 RCX: ffffffff8769f8d5 RDX: 0000000000000000 RSI: ffffffff89024e74 RDI: ffffffff87afd320 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed103eac672d R10: ffff8881f563396b R11: 0000000000000000 R12: 0000000000000000 R13: fffffbfff1285d48 R14: 0000000000000000 R15: ffffffff8af01fd0 arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x464/0x590 kernel/sched/idle.c:352 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451 rest_init+0x251/0x260 init/main.c:760 start_kernel+0x47a/0x480 init/main.c:1210 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10e2ab flags: 0x200000000000000(node=0|zone=2) raw: 0200000000000000 0000000000000000 00000000ffffffff 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 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4893, tgid 4893 (modprobe), ts 96848209805, free_ts 142214239258 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_slab_page mm/slub.c:3292 [inline] allocate_slab mm/slub.c:3481 [inline] new_slab+0xa6/0x6c0 mm/slub.c:3539 refill_objects+0x26b/0x400 mm/slub.c:7175 refill_sheaf mm/slub.c:2812 [inline] __prefill_sheaf_pfmemalloc+0x5f/0xb0 mm/slub.c:4936 kmem_cache_prefill_sheaf+0x1ba/0x4c0 mm/slub.c:5025 mt_get_sheaf lib/maple_tree.c:189 [inline] mas_alloc_nodes+0x2c3/0x390 lib/maple_tree.c:1140 mas_preallocate+0x39c/0xf10 lib/maple_tree.c:5194 vma_iter_prealloc mm/vma.h:568 [inline] __mmap_new_vma mm/vma.c:2526 [inline] __mmap_region+0x11c9/0x26e0 mm/vma.c:2759 mmap_region+0x180/0x3e0 mm/vma.c:2837 do_mmap+0xc53/0x12d0 mm/mmap.c:559 vm_mmap_pgoff+0x201/0x390 mm/util.c:581 ksys_mmap_pgoff+0xe1/0x650 mm/mmap.c:605 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0x7b0 arch/x86/entry/syscall_64.c:94 page last free pid 5405 tgid 5405 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 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4538 [inline] slab_alloc_node mm/slub.c:4866 [inline] kmem_cache_alloc_lru_noprof+0x2ec/0x6b0 mm/slub.c:4885 __d_alloc+0x34/0xa80 fs/dcache.c:1740 d_alloc_parallel+0x111/0x14e0 fs/dcache.c:2604 lookup_open.isra.0+0x57c/0x11b0 fs/namei.c:4404 open_last_lookups fs/namei.c:4589 [inline] path_openat+0x2291/0x31a0 fs/namei.c:4833 do_file_open+0x20e/0x430 fs/namei.c:4865 do_sys_openat2+0x10d/0x1e0 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1383 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 Memory state around the buggy address: ffff88810e2abe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88810e2abf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88810e2abf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88810e2ac000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88810e2ac080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: b0 01 mov $0x1,%al 2: e9 53 e8 02 00 jmp 0x2e85a 7: 0f 1f 00 nopl (%rax) a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: f3 0f 1e fa endbr64 1e: 66 90 xchg %ax,%ax 20: 0f 00 2d 33 87 1c 00 verw 0x1c8733(%rip) # 0x1c875a 27: fb sti 28: f4 hlt * 29: c3 ret <-- trapping instruction 2a: cc int3 2b: cc int3 2c: cc int3 2d: cc int3 2e: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 35: 00 00 00 38: 66 90 xchg %ax,%ax 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop