==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:957
Read of size 1 at addr ffff888048413fff by task syz-executor/7390
CPU: 0 UID: 0 PID: 7390 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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: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+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:debug_object_init_on_stack+0xb/0x20 lib/debugobjects.c:819
Code: e5 fd ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 80 3d ad bc 58 0b 00 <74> 06 c3 cc cc cc cc cc ba 01 00 00 00 e9 f3 fa ff ff 0f 1f 00 90
RSP: 0018:ffffc90004557cf8 EFLAGS: 00000246
RAX: ffffc90004557d40 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8bcf5e40 RDI: ffffc90004557d40
RBP: ffffc90004557e10 R08: ffffc90004557d97 R09: 0000000000000000
R10: ffffc90004557d40 R11: fffff520008aafb3 R12: 0000000000000000
R13: ffffc90004557d40 R14: 0000000000000001 R15: 1ffff920008aafa4
debug_hrtimer_init_on_stack kernel/time/hrtimer.c:480 [inline]
debug_setup_on_stack kernel/time/hrtimer.c:522 [inline]
hrtimer_setup_sleeper_on_stack kernel/time/hrtimer.c:2259 [inline]
hrtimer_nanosleep+0xca/0x3a0 kernel/time/hrtimer.c:2336
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1391 [inline]
__se_sys_clock_nanosleep+0x35b/0x3b0 kernel/time/posix-timers.c:1368
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
RIP: 0033:0x7f8ab335cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffcfd0bcf78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055556cd7d500 RCX: 00007f8ab335cfce
RDX: 00007ffcfd0bcfd0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffcfd0bd03c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388
R13: 00000000000927c0 R14: 00000000000899d6 R15: 00007ffcfd0bd090
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888000000000 pfn:0x48413
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 dead000000000100 dead000000000122 0000000000000000
raw: ffff888000000000 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 0x402dc2(GFP_KERNEL_ACCOUNT|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 16978, tgid 16977 (syz.5.3634), ts 524062774258, free_ts 524229127871
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1859
prep_new_page mm/page_alloc.c:1867 [inline]
get_page_from_freelist+0x2418/0x24b0 mm/page_alloc.c:3926
__alloc_frozen_pages_noprof+0x233/0x3d0 mm/page_alloc.c:5213
__alloc_pages_noprof+0x10/0x100 mm/page_alloc.c:5247
alloc_pages_bulk_noprof+0x5ff/0x7c0 mm/page_alloc.c:5167
alloc_pages_bulk_mempolicy_noprof+0x34e/0x1680 mm/mempolicy.c:2792
vm_area_alloc_pages mm/vmalloc.c:3700 [inline]
__vmalloc_area_node mm/vmalloc.c:3878 [inline]
__vmalloc_node_range_noprof+0xad1/0x1750 mm/vmalloc.c:4064
__vmalloc_node_noprof mm/vmalloc.c:4124 [inline]
__vmalloc_noprof+0xd2/0x120 mm/vmalloc.c:4140
kvm_alloc_memslot_metadata arch/x86/kvm/x86.c:13592 [inline]
kvm_arch_prepare_memory_region+0x7ce/0xee0 arch/x86/kvm/x86.c:13669
kvm_prepare_memory_region virt/kvm/kvm_main.c:1696 [inline]
kvm_set_memslot+0x585/0x1220 virt/kvm/kvm_main.c:1941
kvm_set_memory_region+0x93c/0xb90 virt/kvm/kvm_main.c:2122
kvm_vm_ioctl_set_memory_region+0x66/0xb0 virt/kvm/kvm_main.c:2156
kvm_vm_ioctl+0xa58/0xd50 virt/kvm/kvm_main.c:5210
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+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 16977 tgid 16977 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1403 [inline]
__free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2944
vfree+0x1d1/0x2f0 mm/vmalloc.c:3472
kvm_arch_free_memslot+0x13e/0x170 arch/x86/kvm/x86.c:13536
kvm_free_memslot virt/kvm/kvm_main.c:951 [inline]
kvm_free_memslots+0x15b/0x200 virt/kvm/kvm_main.c:972
kvm_destroy_vm virt/kvm/kvm_main.c:1307 [inline]
kvm_put_kvm+0x8b2/0xa50 virt/kvm/kvm_main.c:1340
kvm_vm_release+0x43/0x50 virt/kvm/kvm_main.c:1363
__fput+0x44f/0xa70 fs/file_table.c:469
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff888048413e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff888048413f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888048413f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff888048414000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888048414080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess), 3 bytes skipped:
0: ff 66 66 jmp *0x66(%rsi)
3: 2e 0f 1f 84 00 00 00 cs nopl 0x0(%rax,%rax,1)
a: 00 00
c: 90 nop
d: 90 nop
e: 90 nop
f: 90 nop
10: 90 nop
11: 90 nop
12: 90 nop
13: 90 nop
14: 90 nop
15: 90 nop
16: 90 nop
17: 90 nop
18: 90 nop
19: 90 nop
1a: 90 nop
1b: 90 nop
1c: f3 0f 1e fa endbr64
20: 80 3d ad bc 58 0b 00 cmpb $0x0,0xb58bcad(%rip) # 0xb58bcd4
* 27: 74 06 je 0x2f <-- trapping instruction
29: c3 ret
2a: cc int3
2b: cc int3
2c: cc int3
2d: cc int3
2e: cc int3
2f: ba 01 00 00 00 mov $0x1,%edx
34: e9 f3 fa ff ff jmp 0xfffffb2c
39: 0f 1f 00 nopl (%rax)
3c: 90 nop