================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x103c/0x10a0 drivers/hid/hid-mcp2221.c:950 Read of size 1 at addr ffff88812dc63fff by task kworker/0:7/16511 CPU: 0 UID: 0 PID: 16511 Comm: kworker/0:7 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events legacy_dvb_usb_read_remote_control 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: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+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:console_flush_one_record+0xac3/0xe50 kernel/printk/printk.c:3270 Code: 00 e8 d1 61 28 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 1f 67 20 00 48 85 ed 0f 85 d7 01 00 00 e8 31 6c 20 00 fb 4c 89 e8 <48> c1 e8 03 42 80 3c 38 00 0f 85 64 03 00 00 48 8b 0c 24 48 8b 6b RSP: 0018:ffffc900068cf7e0 EFLAGS: 00000293 RAX: ffffffff89c75c78 RBX: ffffffff89c75c20 RCX: ffffffff819178e1 RDX: ffff8881224ad880 RSI: ffffffff819178ef RDI: ffff8881224ad880 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 000000000004dc48 R13: ffffffff89c75c78 R14: ffffc900068cf860 R15: dffffc0000000000 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479 _printk+0xcf/0x110 kernel/printk/printk.c:2504 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_query.cold+0x2b/0x30 drivers/media/usb/dvb-usb/m920x.c:188 legacy_dvb_usb_read_remote_control+0x10c/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 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 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888100000000 pfn:0x12dc63 flags: 0x200000000000000(node=0|zone=2) raw: 0200000000000000 dead000000000100 dead000000000122 0000000000000000 raw: ffff888100000000 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 0xcc0(GFP_KERNEL), pid 13553, tgid 13553 (syz-executor), ts 3050746479753, free_ts 3112045134824 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_noprof mm/page_alloc.c:5284 [inline] alloc_pages_bulk_noprof+0x747/0x1240 mm/page_alloc.c:5204 ___alloc_pages_bulk mm/kasan/shadow.c:345 [inline] __kasan_populate_vmalloc_do mm/kasan/shadow.c:370 [inline] __kasan_populate_vmalloc+0xf0/0x210 mm/kasan/shadow.c:424 kasan_populate_vmalloc include/linux/kasan.h:580 [inline] alloc_vmap_area+0x95d/0x2bd0 mm/vmalloc.c:2129 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3232 __vmalloc_node_range_noprof+0x213/0x1530 mm/vmalloc.c:4024 vmalloc_user_noprof+0x9e/0xe0 mm/vmalloc.c:4218 kcov_ioctl+0x4c/0x720 kernel/kcov.c:726 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 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 7701 tgid 7701 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 kasan_depopulate_vmalloc_pte+0x5d/0x80 mm/kasan/shadow.c:484 apply_to_pte_range mm/memory.c:3243 [inline] apply_to_pmd_range mm/memory.c:3287 [inline] apply_to_pud_range mm/memory.c:3323 [inline] apply_to_p4d_range mm/memory.c:3359 [inline] __apply_to_page_range+0xb1d/0x1520 mm/memory.c:3395 __kasan_release_vmalloc+0xd7/0xe0 mm/kasan/shadow.c:602 kasan_release_vmalloc include/linux/kasan.h:593 [inline] kasan_release_vmalloc_node mm/vmalloc.c:2290 [inline] purge_vmap_node+0x210/0xb40 mm/vmalloc.c:2312 __purge_vmap_area_lazy+0x935/0xc20 mm/vmalloc.c:2402 drain_vmap_area_work+0x27/0x40 mm/vmalloc.c:2436 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 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: ffff88812dc63e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88812dc63f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88812dc63f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88812dc64000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88812dc64080: 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: d1 61 28 shll $1,0x28(%rcx) 5: 00 9c 5d 81 e5 00 02 add %bl,0x200e581(%rbp,%rbx,2) c: 00 00 add %al,(%rax) e: 31 ff xor %edi,%edi 10: 48 89 ee mov %rbp,%rsi 13: e8 1f 67 20 00 call 0x206737 18: 48 85 ed test %rbp,%rbp 1b: 0f 85 d7 01 00 00 jne 0x1f8 21: e8 31 6c 20 00 call 0x206c57 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 85 64 03 00 00 jne 0x39d 39: 48 8b 0c 24 mov (%rsp),%rcx 3d: 48 rex.W 3e: 8b .byte 0x8b 3f: 6b .byte 0x6b