==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:957
Read of size 1 at addr ffff888074cfffff by task syz.2.4370/16628
CPU: 0 UID: 0 PID: 16628 Comm: syz.2.4370 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:957
__hid_input_report drivers/hid/hid-core.c:2139 [inline]
hid_input_report+0x41d/0x580 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:1657
dummy_timer+0xbc0/0x4650 drivers/usb/gadget/udc/dummy_hcd.c:2005
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994
hrtimer_run_softirq+0x17a/0x240 kernel/time/hrtimer.c:2011
handle_softirqs+0x22a/0x840 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:finish_task_switch+0x427/0xbe0 kernel/sched/core.c:5211
Code: 41 c7 84 24 e0 0d 00 00 00 00 00 00 0f 1f 44 00 00 49 83 c4 48 4c 89 e7 e8 76 4b 27 0a e8 61 b5 38 00 fb 49 8d bd 68 16 00 00 <48> 89 f8 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 7b 03 00 00 41 80
RSP: 0018:ffffc9000586f850 EFLAGS: 00000202
RAX: 000000000000050d RBX: 1ffff110170c777c RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8e106c7e RDI: ffff8880227934e8
RBP: ffffc9000586f8b0 R08: ffffffff9033bef7 R09: 1ffffffff20677de
R10: dffffc0000000000 R11: fffffbfff20677df R12: ffff8880b863ae48
R13: ffff888022791e80 R14: ffff888029b60000 R15: dffffc0000000000
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1664/0x5520 kernel/sched/core.c:6966
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7151
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
_raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:198
spin_unlock_irqrestore include/linux/spinlock.h:408 [inline]
raw_ioctl_run drivers/usb/gadget/legacy/raw_gadget.c:611 [inline]
raw_ioctl+0x181d/0x41c0 drivers/usb/gadget/legacy/raw_gadget.c:1307
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f85dd59c4ab
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007f85de469f00 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00007f85dd59c4ab
RDX: 0000000000000000 RSI: 0000000000005501 RDI: 0000000000000006
RBP: 00007f85de46afd0 R08: 0000000000000001 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000200000000040 R14: 0000000000000000 R15: 0000000000000868
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffffffff00000000 pfn:0x74cff
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: ffffffff00000000 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 32499, tgid 32498 (syz.7.2954), ts 670950957105, free_ts 672604773322
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858
prep_new_page mm/page_alloc.c:1866 [inline]
get_page_from_freelist+0x24ba/0x2540 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226
__alloc_pages_noprof+0x10/0x100 mm/page_alloc.c:5260
alloc_pages_bulk_noprof+0x5ff/0x7c0 mm/page_alloc.c:5180
___alloc_pages_bulk mm/kasan/shadow.c:345 [inline]
__kasan_populate_vmalloc_do mm/kasan/shadow.c:370 [inline]
__kasan_populate_vmalloc+0xc1/0x1d0 mm/kasan/shadow.c:424
kasan_populate_vmalloc include/linux/kasan.h:580 [inline]
alloc_vmap_area+0xd47/0x1480 mm/vmalloc.c:2123
__get_vm_area_node+0x1f8/0x300 mm/vmalloc.c:3226
__vmalloc_node_range_noprof+0x36a/0x1750 mm/vmalloc.c:4024
vmalloc_user_noprof+0xad/0xe0 mm/vmalloc.c:4218
vb2_vmalloc_alloc+0xef/0x360 drivers/media/common/videobuf2/videobuf2-vmalloc.c:47
__vb2_buf_mem_alloc drivers/media/common/videobuf2/videobuf2-core.c:242 [inline]
__vb2_queue_alloc+0x9c5/0x15a0 drivers/media/common/videobuf2/videobuf2-core.c:523
vb2_core_reqbufs+0xc1f/0x1410 drivers/media/common/videobuf2/videobuf2-core.c:958
vb2_ioctl_reqbufs+0x4c0/0x830 drivers/media/common/videobuf2/videobuf2-v4l2.c:1036
__video_do_ioctl+0xadb/0xca0 drivers/media/v4l2-core/v4l2-ioctl.c:3133
video_usercopy+0x876/0x1450 drivers/media/v4l2-core/v4l2-ioctl.c:3475
page last free pid 10 tgid 10 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943
kasan_depopulate_vmalloc_pte+0x6d/0x90 mm/kasan/shadow.c:484
apply_to_pte_range mm/memory.c:3322 [inline]
apply_to_pmd_range mm/memory.c:3366 [inline]
apply_to_pud_range mm/memory.c:3402 [inline]
apply_to_p4d_range mm/memory.c:3438 [inline]
__apply_to_page_range+0xbdc/0x1420 mm/memory.c:3474
__kasan_release_vmalloc+0xa2/0xd0 mm/kasan/shadow.c:602
kasan_release_vmalloc include/linux/kasan.h:593 [inline]
kasan_release_vmalloc_node mm/vmalloc.c:2284 [inline]
purge_vmap_node+0x220/0x960 mm/vmalloc.c:2306
__purge_vmap_area_lazy+0x779/0xb40 mm/vmalloc.c:2396
drain_vmap_area_work+0x27/0x40 mm/vmalloc.c:2430
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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:
ffff888074cffe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff888074cfff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888074cfff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff888074d00000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888074d00080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: 41 c7 84 24 e0 0d 00 movl $0x0,0xde0(%r12)
7: 00 00 00 00 00
c: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
11: 49 83 c4 48 add $0x48,%r12
15: 4c 89 e7 mov %r12,%rdi
18: e8 76 4b 27 0a call 0xa274b93
1d: e8 61 b5 38 00 call 0x38b583
22: fb sti
23: 49 8d bd 68 16 00 00 lea 0x1668(%r13),%rdi
* 2a: 48 89 f8 mov %rdi,%rax <-- trapping instruction
2d: 48 c1 e8 03 shr $0x3,%rax
31: 42 0f b6 04 38 movzbl (%rax,%r15,1),%eax
36: 84 c0 test %al,%al
38: 0f 85 7b 03 00 00 jne 0x3b9
3e: 41 rex.B
3f: 80 .byte 0x80