================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff8881379b7fff by task kworker/0:4/5244 CPU: 0 UID: 0 PID: 5244 Comm: kworker/0:4 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: usb_hub_wq hub_event 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+0x314/0x450 drivers/hid/hid-core.c:2130 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+0x1809/0x3a00 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x208/0x8d0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_flush_all+0x9a2/0xc60 kernel/printk/printk.c:3227 Code: 00 e8 62 85 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 c0 a5 20 00 48 85 db 0f 85 55 01 00 00 e8 42 aa 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 77 dc 7e RSP: 0018:ffffc90002367198 EFLAGS: 00000283 RAX: ffffffff897db958 RBX: 0000000000000000 RCX: ffffc9000f3a9000 RDX: 0000000000100000 RSI: ffffffff815d50ae RDI: 0000000000000007 RBP: 0000000000000001 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff897db958 R13: ffffffff897db900 R14: ffffc90002367228 R15: dffffc0000000000 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 dev_vprintk_emit drivers/base/core.c:4914 [inline] dev_printk_emit+0xfa/0x140 drivers/base/core.c:4925 __dev_printk+0xf5/0x270 drivers/base/core.c:4937 _dev_notice+0xe4/0x120 drivers/base/core.c:4982 usb_parse_endpoint drivers/usb/core/config.c:490 [inline] usb_parse_interface drivers/usb/core/config.c:636 [inline] usb_parse_configuration drivers/usb/core/config.c:849 [inline] usb_get_configuration+0x40be/0x6330 drivers/usb/core/config.c:998 usb_enumerate_device drivers/usb/core/hub.c:2526 [inline] usb_new_device+0x11d3/0x1a60 drivers/usb/core/hub.c:2664 hub_port_connect drivers/usb/core/hub.c:5566 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x2fce/0x5060 drivers/usb/core/hub.c:5952 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x56d/0x700 arch/x86/kernel/process.c:148 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:0x0 pfn:0x1379b7 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 8524, tgid 8524 (modprobe), ts 445143394929, free_ts 494423071209 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0xf98/0x2ce0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x259/0x21e0 mm/page_alloc.c:5148 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2492 [inline] allocate_slab mm/slub.c:2660 [inline] new_slab+0x247/0x330 mm/slub.c:2714 ___slab_alloc+0xc55/0x1620 mm/slub.c:3901 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3992 __slab_alloc_node mm/slub.c:4067 [inline] slab_alloc_node mm/slub.c:4228 [inline] kmem_cache_alloc_noprof+0x1f9/0x3b0 mm/slub.c:4247 mt_alloc_one lib/maple_tree.c:176 [inline] mas_alloc_nodes+0x18b/0x8b0 lib/maple_tree.c:1255 mas_node_count_gfp+0x105/0x130 lib/maple_tree.c:1337 mas_preallocate+0x7e0/0xde0 lib/maple_tree.c:5537 vma_iter_prealloc mm/vma.h:462 [inline] __split_vma+0x34a/0x1040 mm/vma.c:528 vms_gather_munmap_vmas+0x1d2/0x12c0 mm/vma.c:1359 __mmap_prepare mm/vma.c:2359 [inline] __mmap_region+0x436/0x25d0 mm/vma.c:2651 mmap_region+0x1ab/0x3f0 mm/vma.c:2739 do_mmap+0xa2e/0x11f0 mm/mmap.c:558 page last free pid 9756 tgid 9756 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x78a/0xfd0 mm/page_alloc.c:2895 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4191 [inline] slab_alloc_node mm/slub.c:4240 [inline] kmem_cache_alloc_noprof+0x14f/0x3b0 mm/slub.c:4247 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:322 getname include/linux/fs.h:2919 [inline] do_sys_openat2+0xb8/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8881379b7e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881379b7f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8881379b7f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8881379b8000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881379b8080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: e8 62 85 28 00 call 0x288567 5: 9c pushf 6: 5b pop %rbx 7: 81 e3 00 02 00 00 and $0x200,%ebx d: 31 ff xor %edi,%edi f: 48 89 de mov %rbx,%rsi 12: e8 c0 a5 20 00 call 0x20a5d7 17: 48 85 db test %rbx,%rbx 1a: 0f 85 55 01 00 00 jne 0x175 20: e8 42 aa 20 00 call 0x20aa67 25: fb sti 26: 4c 89 e0 mov %r12,%rax * 29: 48 c1 e8 03 shr $0x3,%rax <-- trapping instruction 2d: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 32: 0f 84 11 ff ff ff je 0xffffff49 38: 4c 89 e7 mov %r12,%rdi 3b: e8 .byte 0xe8 3c: 77 dc ja 0x1a 3e: 7e .byte 0x7e