================================================================== BUG: KASAN: use-after-free in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:948 Read of size 1 at addr ffff888053513fff by task kworker/0:3/984 CPU: 0 UID: 0 PID: 984 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:948 __hid_input_report drivers/hid/hid-core.c:2139 [inline] hid_input_report+0x40a/0x520 drivers/hid/hid-core.c:2166 hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1661 dummy_timer+0x85f/0x44c0 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1858 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5193 Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 e9 27 05 00 00 4c 8b 75 d0 4c 89 e7 e8 ef eb bd 09 e8 ca b8 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 58 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc9000390dc38 EFLAGS: 00000282 RAX: beb9bce534419800 RBX: 0000000000000000 RCX: beb9bce534419800 RDX: 0000000000000006 RSI: ffffffff8d7ea803 RDI: ffffffff8bc07de0 RBP: ffffc9000390dc90 R08: ffffffff8f9e3377 R09: 1ffffffff1f3c66e R10: dffffc0000000000 R11: fffffbfff1f3c66f R12: ffff8880261c0000 R13: dffffc0000000000 R14: ffff888032939e40 R15: ffff8880b863abd8 context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17a0/0x4cc0 kernel/sched/core.c:6929 preempt_schedule_notrace+0xd1/0x110 kernel/sched/core.c:7206 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13 rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:752 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5831 sched_submit_work kernel/sched/core.c:6967 [inline] schedule+0xb1/0x360 kernel/sched/core.c:7025 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185 __down_write_common kernel/locking/rwsem.c:1317 [inline] __down_write kernel/locking/rwsem.c:1326 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591 kernfs_add_one+0x41/0x520 fs/kernfs/dir.c:791 kernfs_create_dir_ns+0xde/0x130 fs/kernfs/dir.c:1093 internal_create_group+0x419/0x1110 fs/sysfs/group.c:170 dpm_sysfs_add+0x6a/0x270 drivers/base/power/sysfs.c:699 device_add+0x4d8/0xb50 drivers/base/core.c:3649 cdev_device_add+0x1d6/0x390 fs/char_dev.c:556 i2cdev_attach_adapter+0x2ed/0x4e0 drivers/i2c/i2c-dev.c:691 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 bus_notify+0x143/0x180 drivers/base/bus.c:1001 device_add+0x54d/0xb50 drivers/base/core.c:3669 i2c_register_adapter+0x4f1/0x10f0 drivers/i2c/i2c-core-base.c:1573 devm_i2c_add_adapter+0x1b/0x80 drivers/i2c/i2c-core-base.c:1845 mcp2221_probe+0x404/0x880 drivers/hid/hid-mcp2221.c:1289 __hid_device_probe drivers/hid/hid-core.c:2775 [inline] hid_device_probe+0x416/0x7a0 drivers/hid/hid-core.c:2812 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 hid_add_device+0x272/0x3e0 drivers/hid/hid-core.c:2951 usbhid_probe+0xe13/0x12a0 drivers/hid/usbhid/hid-core.c:1435 usb_probe_interface+0x668/0xc30 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x390 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_new_device+0xa39/0x16f0 drivers/usb/core/hub.c:2689 hub_port_connect drivers/usb/core/hub.c:5561 [inline] hub_port_connect_change drivers/usb/core/hub.c:5701 [inline] port_event drivers/usb/core/hub.c:5865 [inline] hub_event+0x2958/0x4a20 drivers/usb/core/hub.c:5947 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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:0x0 pfn:0x53513 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 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 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5981, tgid 5981 (syz.4.11), ts 102814102771, free_ts 121449599742 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3039 [inline] allocate_slab+0x96/0x3a0 mm/slub.c:3212 new_slab mm/slub.c:3266 [inline] ___slab_alloc+0xe94/0x18a0 mm/slub.c:4636 __slab_alloc+0x65/0x100 mm/slub.c:4755 __slab_alloc_node mm/slub.c:4831 [inline] slab_alloc_node mm/slub.c:5253 [inline] kmem_cache_alloc_node_noprof+0x4c5/0x710 mm/slub.c:5317 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:579 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670 skb_copy+0x188/0x800 net/core/skbuff.c:2125 mac80211_hwsim_tx_frame_no_nl+0xcd3/0x11c0 drivers/net/wireless/virtual/mac80211_hwsim.c:1891 mac80211_hwsim_tx_frame+0x1b5/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2258 mac80211_hwsim_beacon_tx+0x3f0/0x860 drivers/net/wireless/virtual/mac80211_hwsim.c:2359 __iterate_interfaces+0x2ab/0x590 net/mac80211/util.c:761 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:797 page last free pid 6174 tgid 6174 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906 __slab_free+0x2e7/0x390 mm/slub.c:5947 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4955 [inline] slab_alloc_node mm/slub.c:5265 [inline] __do_kmalloc_node mm/slub.c:5626 [inline] __kmalloc_noprof+0x3c3/0x7f0 mm/slub.c:5639 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80 tomoyo_path_perm+0x2b3/0x4b0 security/tomoyo/file.c:831 tomoyo_path_symlink+0xa3/0xe0 security/tomoyo/tomoyo.c:212 security_path_symlink+0x177/0x380 security/security.c:2023 do_symlinkat+0x107/0x3f0 fs/namei.c:4841 __do_sys_symlinkat fs/namei.c:4859 [inline] __se_sys_symlinkat fs/namei.c:4856 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4856 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888053513e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888053513f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888053513f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888053514000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888053514080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 0f 84 3c 01 00 00 je 0x142 6: 48 85 db test %rbx,%rbx 9: 0f 85 63 01 00 00 jne 0x172 f: e9 27 05 00 00 jmp 0x53b 14: 4c 8b 75 d0 mov -0x30(%rbp),%r14 18: 4c 89 e7 mov %r12,%rdi 1b: e8 ef eb bd 09 call 0x9bdec0f 20: e8 ca b8 36 00 call 0x36b8ef 25: fb sti 26: 4c 8b 65 c0 mov -0x40(%rbp),%r12 * 2a: 49 8d bc 24 58 16 00 lea 0x1658(%r12),%rdi <-- trapping instruction 31: 00 32: 48 89 f8 mov %rdi,%rax 35: 48 c1 e8 03 shr $0x3,%rax 39: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 3e: 84 c0 test %al,%al