==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x110d/0x1140 drivers/hid/hid-mcp2221.c:975
Read of size 1 at addr ffff8881188e7fff by task pr/ttyS0/15
CPU: 1 UID: 0 PID: 15 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
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+0x110d/0x1140 drivers/hid/hid-mcp2221.c:975
__hid_input_report.constprop.0+0x319/0x470 drivers/hid/hid-core.c:2175
hid_irq_in+0x55d/0x710 drivers/hid/usbhid/hid-core.c:287
__usb_hcd_giveback_urb+0x38e/0x610 drivers/usb/core/hcd.c:1657
usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
dummy_timer+0xdaf/0x3820 drivers/usb/gadget/udc/dummy_hcd.c:2023
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2131
hrtimer_run_softirq+0x1ca/0x360 kernel/time/hrtimer.c:2148
handle_softirqs+0x1d9/0x9b0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0x168/0x210 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:221
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 b6 67 04 fa 48 89 df e8 3e be 04 fa f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 75 02 f7 f9 65 48 83 3d b4 0e 98 05 00 74 16 5b
RSP: 0018:ffffc900000ffcb8 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff944978e0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff892df1e1 RDI: ffffffff87d2bd80
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 205d313733375420 R12: 1ffff9200001ff9a
R13: ffffffff89ebc480 R14: 0000000000000001 R15: 0000000000000001
nbcon_emit_one+0x15c/0x2b0 kernel/printk/nbcon.c:1165
nbcon_kthread_func+0x613/0x7d0 kernel/printk/nbcon.c:1271
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x69f/0xc90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Allocated by task 5478:
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:409 [inline]
__kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:426
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5414 [inline]
__kmalloc_node_track_caller_noprof+0x323/0x820 mm/slub.c:5545
kmalloc_reserve+0xe8/0x350 net/core/skbuff.c:637
__alloc_skb+0x185/0x710 net/core/skbuff.c:715
alloc_skb include/linux/skbuff.h:1384 [inline]
alloc_skb_with_frags+0xdd/0x760 net/core/skbuff.c:6799
sock_alloc_send_pskb+0x801/0x980 net/core/sock.c:3022
unix_dgram_sendmsg+0x3c7/0x1810 net/unix/af_unix.c:2144
sock_sendmsg_nosec net/socket.c:800 [inline]
__sock_sendmsg net/socket.c:815 [inline]
sock_write_iter+0x53a/0x5b0 net/socket.c:1266
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x1f8/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x119/0x710 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 2865:
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:264 [inline]
__kasan_slab_free+0x43/0x70 mm/kasan/common.c:296
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6509 [inline]
kfree+0x20c/0x650 mm/slub.c:6802
skb_kfree_head net/core/skbuff.c:1083 [inline]
skb_free_head+0xb9/0x160 net/core/skbuff.c:1095
skb_release_data+0x659/0x860 net/core/skbuff.c:1122
skb_release_all net/core/skbuff.c:1197 [inline]
__kfree_skb net/core/skbuff.c:1211 [inline]
consume_skb net/core/skbuff.c:1448 [inline]
consume_skb+0xc4/0x110 net/core/skbuff.c:1442
__unix_dgram_recvmsg+0x754/0xc30 net/unix/af_unix.c:2672
unix_dgram_recvmsg+0xcd/0x100 net/unix/af_unix.c:2689
sock_recvmsg_nosec net/socket.c:1151 [inline]
sock_recvmsg+0x1d5/0x220 net/socket.c:1173
____sys_recvmsg+0x21e/0x670 net/socket.c:2933
___sys_recvmsg+0x16a/0x1a0 net/socket.c:2975
__sys_recvmsg net/socket.c:3008 [inline]
__do_sys_recvmsg net/socket.c:3014 [inline]
__se_sys_recvmsg net/socket.c:3011 [inline]
__x64_sys_recvmsg+0x19a/0x260 net/socket.c:3011
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x119/0x710 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8881188e7c00
which belongs to the cache kmalloc-cg-512 of size 512
The buggy address is located 511 bytes to the right of
allocated 512-byte region [ffff8881188e7c00, ffff8881188e7e00)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1188e4
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8881188e4211
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff88810004b140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000300100010 00000000f5000000 ffff8881188e4211
head: 0200000000000040 ffff88810004b140 dead000000000100 dead000000000122
head: 0000000000000000 0000000300100010 00000000f5000000 ffff8881188e4211
head: 0200000000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2854, tgid 2854 (klogd), ts 177275268762
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0xf4b/0x3440 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2d7/0x2f70 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3347 [inline]
allocate_slab mm/slub.c:3462 [inline]
new_slab+0xa9/0x6e0 mm/slub.c:3513
refill_objects+0xe3/0x410 mm/slub.c:7418
refill_sheaf mm/slub.c:2885 [inline]
__pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
alloc_from_pcs mm/slub.c:4850 [inline]
slab_alloc_node mm/slub.c:4984 [inline]
__do_kmalloc_node mm/slub.c:5413 [inline]
__kmalloc_node_track_caller_noprof+0x634/0x820 mm/slub.c:5545
kmalloc_reserve+0xe8/0x350 net/core/skbuff.c:637
__alloc_skb+0x185/0x710 net/core/skbuff.c:715
alloc_skb include/linux/skbuff.h:1384 [inline]
alloc_skb_with_frags+0xdd/0x760 net/core/skbuff.c:6799
sock_alloc_send_pskb+0x801/0x980 net/core/sock.c:3022
unix_dgram_sendmsg+0x3c7/0x1810 net/unix/af_unix.c:2144
sock_sendmsg_nosec net/socket.c:800 [inline]
__sock_sendmsg net/socket.c:815 [inline]
__sys_sendto+0x48b/0x4e0 net/socket.c:2281
__do_sys_sendto net/socket.c:2288 [inline]
__se_sys_sendto net/socket.c:2284 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2284
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x119/0x710 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5305 tgid 5305 ts 177250107962 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x714/0xfc0 mm/page_alloc.c:2962
hiddev_free drivers/hid/hid-core.c:772 [inline]
kref_put include/linux/kref.h:65 [inline]
hid_device_release+0x138/0x1a0 drivers/hid/hid-core.c:779
device_release+0xd2/0x270 drivers/base/core.c:2640
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1f7/0x640 lib/kobject.c:737
put_device+0x1f/0x30 drivers/base/core.c:3884
usbhid_probe+0xde5/0x10b0 drivers/hid/usbhid/hid-core.c:1463
usb_probe_interface+0x386/0x980 drivers/usb/core/driver.c:399
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x210/0x460 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3776
Memory state around the buggy address:
ffff8881188e7e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8881188e7f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881188e7f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8881188e8000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8881188e8080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: f5 cmc
1: 53 push %rbx
2: 48 8b 74 24 10 mov 0x10(%rsp),%rsi
7: 48 89 fb mov %rdi,%rbx
a: 48 83 c7 18 add $0x18,%rdi
e: e8 b6 67 04 fa call 0xfa0467c9
13: 48 89 df mov %rbx,%rdi
16: e8 3e be 04 fa call 0xfa04be59
1b: f7 c5 00 02 00 00 test $0x200,%ebp
21: 75 23 jne 0x46
23: 9c pushf
24: 58 pop %rax
25: f6 c4 02 test $0x2,%ah
28: 75 37 jne 0x61
* 2a: bf 01 00 00 00 mov $0x1,%edi <-- trapping instruction
2f: e8 75 02 f7 f9 call 0xf9f702a9
34: 65 48 83 3d b4 0e 98 cmpq $0x0,%gs:0x5980eb4(%rip) # 0x5980ef1
3b: 05 00
3d: 74 16 je 0x55
3f: 5b pop %rbx