==================================================================
BUG: KASAN: use-after-free in mcp2221_raw_event+0x106a/0x1240 drivers/hid/hid-mcp2221.c:950
Read of size 1 at addr ffff88804c12bfff by task syz.1.1152/10220
CPU: 1 UID: 0 PID: 10220 Comm: syz.1.1152 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 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:finish_task_switch+0x245/0x920 kernel/sched/core.c:5155
Code: 00 00 48 85 db 0f 85 e8 01 00 00 e9 56 05 00 00 4c 8b 75 d0 49 83 c4 48 4c 89 e7 e8 15 25 1d 0a e8 10 93 38 00 fb 4c 8b 65 c0 <49> 8d bc 24 80 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc9000d23f958 EFLAGS: 00000202
RAX: 000000000000339d RBX: 0000000000000000 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8defb811 RDI: ffffffff8c27d500
RBP: ffffc9000d23f9b0 R08: ffffffff9011d5b7 R09: 1ffffffff2023ab6
R10: dffffc0000000000 R11: fffffbfff2023ab7 R12: ffff888020319e80
R13: dffffc0000000000 R14: ffff888031f68000 R15: ffff8880b873b998
context_switch kernel/sched/core.c:5301 [inline]
__schedule+0x15e5/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
do_nanosleep+0x1c2/0x620 kernel/time/hrtimer.c:2124
hrtimer_nanosleep+0x188/0x390 kernel/time/hrtimer.c:2171
__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: 0033:0x7ff0a015d04e
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:00007ff0a053fb28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 00005555761d6500 RCX: 00007ff0a015d04e
RDX: 00007ff0a053fb80 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ff0a0417da0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000005caf5
R13: 00007ff0a041618c R14: 000000000005bf6f R15: 00007ff0a0416180
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x7efc9 pfn:0x4c12b
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f0(buddy)
raw: 00fff00000000000 ffffea0000cc2088 ffffea0001466548 0000000000000000
raw: 000000000007efc9 0000000000000000 00000000f0000000 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 0xd00(GFP_NOIO|__GFP_ZERO), pid 10059, tgid 10052 (syz.1.1107), ts 366689836416, free_ts 366908850016
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_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2490
alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
alloc_pages_noprof+0xa8/0x1a0 mm/mempolicy.c:2581
relay_alloc_buf kernel/relay.c:121 [inline]
relay_create_buf kernel/relay.c:160 [inline]
relay_open_buf+0x28c/0xde0 kernel/relay.c:388
relay_open+0x427/0x920 kernel/relay.c:517
blk_trace_setup_prepare+0x425/0x5a0 kernel/trace/blktrace.c:715
blk_trace_setup+0x2f8/0x520 kernel/trace/blktrace.c:789
blk_trace_ioctl+0x37f/0x920 kernel/trace/blktrace.c:937
blkdev_ioctl+0x4c1/0x740 block/ioctl.c:793
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 10060 tgid 10052 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
relay_destroy_buf+0x10e/0x3a0 kernel/relay.c:199
relay_remove_buf kernel/relay.c:219 [inline]
kref_put include/linux/kref.h:65 [inline]
relay_close_buf kernel/relay.c:434 [inline]
relay_close+0x3c7/0x620 kernel/relay.c:663
blk_trace_free+0x3c/0x110 kernel/trace/blktrace.c:471
blk_trace_cleanup kernel/trace/blktrace.c:539 [inline]
__blk_trace_remove+0x22c/0x2c0 kernel/trace/blktrace.c:552
blk_trace_remove kernel/trace/blktrace.c:562 [inline]
blk_trace_ioctl+0x3a2/0x920 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724
blkdev_ioctl+0x528/0x740 block/ioctl.c:798
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
Memory state around the buggy address:
ffff88804c12be80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88804c12bf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88804c12bf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff88804c12c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88804c12c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 48 85 db test %rbx,%rbx
5: 0f 85 e8 01 00 00 jne 0x1f3
b: e9 56 05 00 00 jmp 0x566
10: 4c 8b 75 d0 mov -0x30(%rbp),%r14
14: 49 83 c4 48 add $0x48,%r12
18: 4c 89 e7 mov %r12,%rdi
1b: e8 15 25 1d 0a call 0xa1d2535
20: e8 10 93 38 00 call 0x389335
25: fb sti
26: 4c 8b 65 c0 mov -0x40(%rbp),%r12
* 2a: 49 8d bc 24 80 16 00 lea 0x1680(%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