==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x101c/0x1090 drivers/hid/hid-mcp2221.c:964
Read of size 1 at addr ffff88807bc5ffff by task syz.4.461/7106
CPU: 0 UID: 0 PID: 7106 Comm: syz.4.461 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
mcp2221_raw_event+0x101c/0x1090 drivers/hid/hid-mcp2221.c:964
__hid_input_report.constprop.0+0x319/0x470 drivers/hid/hid-core.c:2168
hid_irq_in+0x55d/0x710 drivers/hid/usbhid/hid-core.c:287
__usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657
usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
dummy_timer+0xda1/0x36c0 drivers/usb/gadget/udc/dummy_hcd.c:2005
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2113
handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:finish_task_switch.isra.0+0x2cd/0x10c0 kernel/sched/core.c:5361
Code: ab 0a 00 00 41 c7 87 20 0e 00 00 00 00 00 00 0f 1f 44 00 00 49 8d 7f 48 e8 30 84 e5 09 e8 fb a7 3c 00 fb 48 8d bb f8 16 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84
RSP: 0018:ffffc900067c7288 EFLAGS: 00000202
RAX: 000000000000723b RBX: ffff88801ef40000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8e1a84ef RDI: ffff88801ef416f8
RBP: ffffc900067c72e0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88807e773e00
R13: 0000000000000000 R14: ffffffff91229c44 R15: ffff8880b843b600
context_switch kernel/sched/core.c:5513 [inline]
__schedule+0x1264/0x6730 kernel/sched/core.c:7234
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7556
irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x205/0xa00 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872
Code: 05 fb fd 7d 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 46 16 3d 0f 0f 82 ac 02 00 00 8b 35 ee 49 3d 0f 85 f6 0f 85 c7 00 00 00 <48> 8b 44 24 30 65 48 2b 05 9d fd 7d 12 0f 85 ec 02 00 00 48 83 c4
RSP: 0018:ffffc900067c7568 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8e182823 RDI: ffffffff8c400580
RBP: ffffffff8ebe6180 R08: 00000000ffffffff R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:840 [inline]
class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4612 [inline]
slab_alloc_node mm/slub.c:4945 [inline]
kmem_cache_alloc_noprof+0x26b/0x6a0 mm/slub.c:4959
alloc_empty_file+0x5b/0x1c0 fs/file_table.c:262
path_openat+0xe7/0x4280 fs/namei.c:4849
do_file_open+0x20e/0x430 fs/namei.c:4892
do_sys_openat2+0x10f/0x1e0 fs/open.c:1368
do_sys_open fs/open.c:1374 [inline]
__do_sys_openat fs/open.c:1390 [inline]
__se_sys_openat fs/open.c:1385 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1385
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f3a75e68e
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:00007f5f3b592ec8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f5f3b5936c0 RCX: 00007f5f3a75e68e
RDX: 0000000000000000 RSI: 00007f5f3b592f90 RDI: ffffffffffffff9c
RBP: 00007f5f3a833e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5f3aa26038 R14: 00007f5f3aa25fa0 R15: 00007ffc3d18b0b8
Allocated by task 5867:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x2e5/0x6c0 mm/slub.c:5515
_kmalloc_noprof include/linux/slab.h:969 [inline]
_kzalloc_noprof include/linux/slab.h:1290 [inline]
kernfs_iop_get_link fs/kernfs/symlink.c:137 [inline]
kernfs_iop_get_link+0x65/0x16a0 fs/kernfs/symlink.c:128
pick_link+0xd17/0x13c0 fs/namei.c:2068
step_into_slowpath+0x9ba/0xf90 fs/namei.c:2127
step_into fs/namei.c:2152 [inline]
open_last_lookups fs/namei.c:4643 [inline]
path_openat+0x13b5/0x4280 fs/namei.c:4860
do_file_open+0x20e/0x430 fs/namei.c:4892
do_sys_openat2+0x10f/0x1e0 fs/open.c:1368
do_sys_open fs/open.c:1374 [inline]
__do_sys_openat fs/open.c:1390 [inline]
__se_sys_openat fs/open.c:1385 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1385
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 5867:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2705 [inline]
slab_free mm/slub.c:6405 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6720
do_delayed_call include/linux/delayed_call.h:28 [inline]
put_link fs/namei.c:1199 [inline]
open_last_lookups fs/namei.c:4642 [inline]
path_openat+0x1312/0x4280 fs/namei.c:4860
do_file_open+0x20e/0x430 fs/namei.c:4892
do_sys_openat2+0x10f/0x1e0 fs/open.c:1368
do_sys_open fs/open.c:1374 [inline]
__do_sys_openat fs/open.c:1390 [inline]
__se_sys_openat fs/open.c:1385 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1385
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807bc5e000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 4095 bytes to the right of
allocated 4096-byte region [ffff88807bc5e000, ffff88807bc5f000)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7bc58
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813fe24140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813fe24140 dead000000000100 dead000000000122
head: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4994, tgid 4994 (udevd), ts 38143460833, free_ts 38124205065
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
prep_new_page mm/page_alloc.c:1867 [inline]
get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
alloc_slab_page mm/slub.c:3294 [inline]
allocate_slab mm/slub.c:3408 [inline]
new_slab+0xa2/0x650 mm/slub.c:3454
refill_objects+0xe3/0x410 mm/slub.c:7338
refill_sheaf mm/slub.c:2832 [inline]
__pcs_replace_empty_main+0x376/0x680 mm/slub.c:4703
alloc_from_pcs mm/slub.c:4801 [inline]
slab_alloc_node mm/slub.c:4933 [inline]
__do_kmalloc_node mm/slub.c:5361 [inline]
__kmalloc_noprof+0x66d/0x820 mm/slub.c:5387
_kmalloc_noprof include/linux/slab.h:973 [inline]
tomoyo_realpath_from_path+0xb6/0x690 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:827
security_inode_getattr+0x116/0x280 security/security.c:1895
vfs_getattr fs/stat.c:259 [inline]
vfs_fstat+0x4b/0xe0 fs/stat.c:281
__do_sys_newfstat+0x8b/0x110 fs/stat.c:551
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 4986 tgid 4986 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4612 [inline]
slab_alloc_node mm/slub.c:4945 [inline]
__do_kmalloc_node mm/slub.c:5361 [inline]
__kvmalloc_node_noprof+0x2eb/0x970 mm/slub.c:6933
seq_buf_alloc fs/seq_file.c:39 [inline]
seq_read_iter+0x819/0x1270 fs/seq_file.c:211
kernfs_fop_read_iter+0x46c/0x610 fs/kernfs/file.c:290
new_sync_read fs/read_write.c:493 [inline]
vfs_read+0x82e/0xb40 fs/read_write.c:574
ksys_read+0x12a/0x250 fs/read_write.c:716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807bc5fe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88807bc5ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807bc5ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88807bc60000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88807bc60080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess), 2 bytes skipped:
0: 00 00 add %al,(%rax)
2: 41 c7 87 20 0e 00 00 movl $0x0,0xe20(%r15)
9: 00 00 00 00
d: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
12: 49 8d 7f 48 lea 0x48(%r15),%rdi
16: e8 30 84 e5 09 call 0x9e5844b
1b: e8 fb a7 3c 00 call 0x3ca81b
20: fb sti
21: 48 8d bb f8 16 00 00 lea 0x16f8(%rbx),%rdi
* 28: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax <-- trapping instruction
2f: fc ff df
32: 48 89 fa mov %rdi,%rdx
35: 48 c1 ea 03 shr $0x3,%rdx
39: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax
3d: 84 .byte 0x84