================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff8881464dbfff by task kworker/1:10/21669 CPU: 1 UID: 0 PID: 21669 Comm: kworker/1:10 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events legacy_dvb_usb_read_remote_control Call Trace: __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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_flush_one_record+0x995/0xc60 kernel/printk/printk.c:3216 Code: 00 e8 4f 65 29 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 4d 49 21 00 48 85 ed 0f 85 8e 01 00 00 e8 6f 4e 21 00 fb 4c 89 e8 <48> c1 e8 03 42 80 3c 38 00 0f 84 b4 fe ff ff 4c 89 ef e8 74 12 83 RSP: 0018:ffffc900042ff788 EFLAGS: 00000293 RAX: ffffffff898160f8 RBX: 0000000000000001 RCX: ffffffff815e9df3 RDX: ffff88810afad7c0 RSI: ffffffff815e9e01 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: ffff88810afae268 R12: 0000000000000001 R13: ffffffff898160f8 R14: ffffffff898160a0 R15: dffffc0000000000 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xef/0x240 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 _printk+0xc7/0x100 kernel/printk/printk.c:2451 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_query+0x496/0x770 drivers/media/usb/dvb-usb/m920x.c:193 legacy_dvb_usb_read_remote_control+0x10c/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123 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 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888100000000 pfn:0x1464db flags: 0x200000000000000(node=0|zone=2) page_type: f0(buddy) raw: 0200000000000000 ffffea00047e3988 ffffea0004e86548 0000000000000000 raw: ffff888100000000 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 16072, tgid 16072 (syz-executor), ts 1665795995023, free_ts 1668019128865 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_mpol+0xe4/0x410 mm/mempolicy.c:2486 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline] alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2577 pagetable_alloc_noprof include/linux/mm.h:3190 [inline] __pte_alloc_one_noprof include/asm-generic/pgalloc.h:76 [inline] pte_alloc_one+0x1e/0x3d0 arch/x86/mm/pgtable.c:18 __pte_alloc+0x6d/0x3f0 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+0x1897/0x4d50 mm/memory.c:1535 dup_mmap+0xbb3/0x1ef0 mm/mmap.c:1827 dup_mm kernel/fork.c:1529 [inline] copy_mm kernel/fork.c:1581 [inline] copy_process+0x6e4f/0x7340 kernel/fork.c:2221 kernel_clone+0xfc/0x910 kernel/fork.c:2651 __do_sys_clone+0xce/0x120 kernel/fork.c:2792 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 0 tgid 0 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 __pagetable_free include/linux/mm.h:3200 [inline] pagetable_free include/linux/mm.h:3224 [inline] pagetable_dtor_free include/linux/mm.h:3328 [inline] __tlb_remove_table include/asm-generic/tlb.h:220 [inline] __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x2b2/0x390 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0x79c/0x15f0 kernel/rcu/tree.c:2857 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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 Memory state around the buggy address: ffff8881464dbe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881464dbf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8881464dbf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8881464dc000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881464dc080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 00 e8 add %ch,%al 2: 4f rex.WRXB 3: 65 29 00 sub %eax,%gs:(%rax) 6: 9c pushf 7: 5d pop %rbp 8: 81 e5 00 02 00 00 and $0x200,%ebp e: 31 ff xor %edi,%edi 10: 48 89 ee mov %rbp,%rsi 13: e8 4d 49 21 00 call 0x214965 18: 48 85 ed test %rbp,%rbp 1b: 0f 85 8e 01 00 00 jne 0x1af 21: e8 6f 4e 21 00 call 0x214e95 26: fb sti 27: 4c 89 e8 mov %r13,%rax * 2a: 48 c1 e8 03 shr $0x3,%rax <-- trapping instruction 2e: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 33: 0f 84 b4 fe ff ff je 0xfffffeed 39: 4c 89 ef mov %r13,%rdi 3c: e8 .byte 0xe8 3d: 74 12 je 0x51 3f: 83 .byte 0x83