==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:950
Read of size 1 at addr ffff888034463fff by task kworker/1:8/6011
CPU: 1 UID: 0 PID: 6011 Comm: kworker/1:8 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: usb_hub_wq hub_event
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xba/0x230 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:950
__hid_input_report drivers/hid/hid-core.c:2140 [inline]
hid_input_report+0x41d/0x580 drivers/hid/hid-core.c:2167
hid_irq_in+0x47e/0x6d0 drivers/hid/usbhid/hid-core.c:286
__usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1657
dummy_timer+0xbbd/0x45d0 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1785 [inline]
__hrtimer_run_queues+0x53a/0xcc0 kernel/time/hrtimer.c:1849
hrtimer_run_softirq+0x182/0x5a0 kernel/time/hrtimer.c:1866
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/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+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x10e/0x23c0 include/linux/rcupdate.h:-1
Code: 1f 85 0e 00 75 1f c6 05 87 1f 85 0e 01 48 c7 c7 e0 a2 c9 8b be 54 03 00 00 48 c7 c2 20 a3 c9 8b e8 17 57 2b 00 4c 89 6c 24 78 <48> 89 5c 24 70 4d 8d 6e 50 4c 89 e8 48 c1 e8 03 48 89 44 24 38 80
RSP: 0018:ffffc900049ce078 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff8190b6a8 RCX: 0000000080000001
RDX: 00000000a89d1756 RSI: ffffffff8c27d0e0 RDI: ffffffff8c27d0a0
RBP: dffffc0000000000 R08: ffffffff81767e95 R09: ffffffff8e75e5e0
R10: dffffc0000000000 R11: ffffffff81b0d0f0 R12: 1ffff92000939c29
R13: ffffc900049ce180 R14: ffffc900049ce148 R15: ffffffff81767e95
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5380
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
device_private_init drivers/base/core.c:3536 [inline]
device_add+0xbe/0xb70 drivers/base/core.c:3587
cdev_device_add+0x1d6/0x390 fs/char_dev.c:553
i2cdev_attach_adapter+0x2ed/0x510 drivers/i2c/i2c-dev.c:690
notifier_call_chain+0x1be/0x400 kernel/notifier.c:85
blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380
bus_notify+0x143/0x180 drivers/base/bus.c:1079
device_add+0x54d/0xb70 drivers/base/core.c:3671
i2c_register_adapter+0x51b/0x1180 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:1291
__hid_device_probe drivers/hid/hid-core.c:2776 [inline]
hid_device_probe+0x416/0x7a0 drivers/hid/hid-core.c:2813
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:721
__driver_probe_device+0x18c/0x320 drivers/base/dd.c:863
driver_probe_device+0x4f/0x240 drivers/base/dd.c:893
__device_attach_driver+0x279/0x430 drivers/base/dd.c:1021
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c5/0x450 drivers/base/dd.c:1093
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148
bus_probe_device+0x12a/0x220 drivers/base/bus.c:613
device_add+0x7b6/0xb70 drivers/base/core.c:3691
hid_add_device+0x272/0x3e0 drivers/hid/hid-core.c:2952
usbhid_probe+0xe3a/0x12f0 drivers/hid/usbhid/hid-core.c:1450
usb_probe_interface+0x668/0xc90 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:721
__driver_probe_device+0x18c/0x320 drivers/base/dd.c:863
driver_probe_device+0x4f/0x240 drivers/base/dd.c:893
__device_attach_driver+0x279/0x430 drivers/base/dd.c:1021
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c5/0x450 drivers/base/dd.c:1093
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148
bus_probe_device+0x12a/0x220 drivers/base/bus.c:613
device_add+0x7b6/0xb70 drivers/base/core.c:3691
usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2266
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
usb_probe_device+0x1c4/0x3b0 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:721
__driver_probe_device+0x18c/0x320 drivers/base/dd.c:863
driver_probe_device+0x4f/0x240 drivers/base/dd.c:893
__device_attach_driver+0x279/0x430 drivers/base/dd.c:1021
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c5/0x450 drivers/base/dd.c:1093
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148
bus_probe_device+0x12a/0x220 drivers/base/bus.c:613
device_add+0x7b6/0xb70 drivers/base/core.c:3691
usb_new_device+0xa08/0x16f0 drivers/usb/core/hub.c:2695
hub_port_connect drivers/usb/core/hub.c:5567 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x2a1c/0x4f30 drivers/usb/core/hub.c:5953
process_one_work kernel/workqueue.c:3276 [inline]
process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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:0xffff888034463660 pfn:0x34463
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: ffff888034463660 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 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 10614, tgid 10614 (dhcpcd-run-hook), ts 588453135188, free_ts 603045296041
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889
prep_new_page mm/page_alloc.c:1897 [inline]
get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_slab_page mm/slub.c:3292 [inline]
allocate_slab+0x77/0x660 mm/slub.c:3481
new_slab mm/slub.c:3539 [inline]
refill_objects+0x331/0x3c0 mm/slub.c:7175
refill_sheaf mm/slub.c:2812 [inline]
__pcs_replace_empty_main+0x2e6/0x730 mm/slub.c:4615
alloc_from_pcs mm/slub.c:4717 [inline]
slab_alloc_node mm/slub.c:4851 [inline]
kmem_cache_alloc_noprof+0x37d/0x650 mm/slub.c:4873
anon_vma_alloc mm/rmap.c:94 [inline]
anon_vma_fork+0x83/0x570 mm/rmap.c:391
dup_mmap+0x991/0x1d90 mm/mmap.c:1804
dup_mm kernel/fork.c:1531 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1583
copy_process+0x18b6/0x3cd0 kernel/fork.c:2223
kernel_clone+0x248/0x8e0 kernel/fork.c:2653
__do_sys_clone kernel/fork.c:2794 [inline]
__se_sys_clone kernel/fork.c:2778 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2778
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 23 tgid 23 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
__free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978
rcu_do_batch kernel/rcu/tree.c:2617 [inline]
rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
run_ksoftirqd+0x36/0x60 kernel/softirq.c:1063
smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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:
ffff888034463e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff888034463f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888034463f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff888034464000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888034464080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 85 0e test %ecx,(%rsi)
2: 00 75 1f add %dh,0x1f(%rbp)
5: c6 05 87 1f 85 0e 01 movb $0x1,0xe851f87(%rip) # 0xe851f93
c: 48 c7 c7 e0 a2 c9 8b mov $0xffffffff8bc9a2e0,%rdi
13: be 54 03 00 00 mov $0x354,%esi
18: 48 c7 c2 20 a3 c9 8b mov $0xffffffff8bc9a320,%rdx
1f: e8 17 57 2b 00 call 0x2b573b
24: 4c 89 6c 24 78 mov %r13,0x78(%rsp)
* 29: 48 89 5c 24 70 mov %rbx,0x70(%rsp) <-- trapping instruction
2e: 4d 8d 6e 50 lea 0x50(%r14),%r13
32: 4c 89 e8 mov %r13,%rax
35: 48 c1 e8 03 shr $0x3,%rax
39: 48 89 44 24 38 mov %rax,0x38(%rsp)
3e: 80 .byte 0x80