==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948
Read of size 1 at addr ffff88807be9bfff by task swapper/0/0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xcd/0x630 mm/kasan/report.c:482
kasan_report+0xe0/0x110 mm/kasan/report.c:595
mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948
__hid_input_report.constprop.0+0x314/0x450 drivers/hid/hid-core.c:2139
hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:286
__usb_hcd_giveback_urb+0x38b/0x610 drivers/usb/core/hcd.c:1661
usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1745
dummy_timer+0x1809/0x3a00 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1841
hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858
handle_softirqs+0x219/0x8e0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:114 [inline]
RIP: 0010:tick_nohz_idle_enter+0x7b/0x270 kernel/time/tick-sched.c:1256
Code: e8 ba f3 0e 00 65 8b 1d 9b fd f3 11 31 ff 89 de e8 ea ee 0e 00 85 db 0f 84 5f 01 00 00 e8 9d f3 0e 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 fa ee 0e 00 48 85 db 0f 85 69 01 00 00 e8 7c
RSP: 0018:ffffffff8e007df0 EFLAGS: 00000206
RAX: 0000000000000000 RBX: 0000000000000200 RCX: ffffffff81adf5b2
RDX: ffffffff8e097a00 RSI: ffffffff81adf443 RDI: 0000000000000005
RBP: ffffffff90824754 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 000000000008b000
do_idle+0x80/0x500 kernel/sched/idle.c:276
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3f6/0x4e0 init/main.c:1111
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148
Allocated by task 5171:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5650 [inline]
__kmalloc_node_track_caller_noprof+0x345/0x8a0 mm/slub.c:5759
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:601
__alloc_skb+0x166/0x380 net/core/skbuff.c:670
alloc_skb include/linux/skbuff.h:1383 [inline]
alloc_skb_with_frags+0xe0/0x860 net/core/skbuff.c:6671
sock_alloc_send_pskb+0x7f9/0x980 net/core/sock.c:2965
unix_dgram_sendmsg+0x3e9/0x17f0 net/unix/af_unix.c:2153
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x4a3/0x520 net/socket.c:2244
__do_sys_sendto net/socket.c:2251 [inline]
__se_sys_sendto net/socket.c:2247 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2247
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 5164:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
__kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587
kasan_save_free_info mm/kasan/kasan.h:406 [inline]
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2543 [inline]
slab_free mm/slub.c:6642 [inline]
kfree+0x2b8/0x6d0 mm/slub.c:6849
skb_kfree_head net/core/skbuff.c:1048 [inline]
skb_free_head+0x114/0x210 net/core/skbuff.c:1060
skb_release_data+0x795/0x9e0 net/core/skbuff.c:1087
skb_release_all net/core/skbuff.c:1152 [inline]
__kfree_skb net/core/skbuff.c:1166 [inline]
consume_skb net/core/skbuff.c:1398 [inline]
consume_skb+0xbf/0x100 net/core/skbuff.c:1392
__unix_dgram_recvmsg+0x779/0xc30 net/unix/af_unix.c:2683
unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2700
sock_recvmsg_nosec net/socket.c:1078 [inline]
sock_recvmsg+0x1f9/0x250 net/socket.c:1100
sock_read_iter+0x2b9/0x3b0 net/socket.c:1170
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0xa98/0xcf0 fs/read_write.c:572
ksys_read+0x1f8/0x250 fs/read_write.c:715
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88807be9bc00
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 [ffff88807be9bc00, ffff88807be9be00)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7be98
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888034925601
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813ffb0140 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000100010 00000000f5000000 ffff888034925601
head: 00fff00000000040 ffff88813ffb0140 0000000000000000 dead000000000001
head: 0000000000000000 0000000000100010 00000000f5000000 ffff888034925601
head: 00fff00000000002 ffffea0001efa601 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 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 5476, tgid 5476 (dhcpcd), ts 35699497657, free_ts 28159477808
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845
prep_new_page mm/page_alloc.c:1853 [inline]
get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3879
__alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5178
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
alloc_slab_page mm/slub.c:3059 [inline]
allocate_slab mm/slub.c:3232 [inline]
new_slab+0x24a/0x360 mm/slub.c:3286
___slab_alloc+0xd79/0x1a50 mm/slub.c:4655
__slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778
__slab_alloc_node mm/slub.c:4854 [inline]
slab_alloc_node mm/slub.c:5276 [inline]
__do_kmalloc_node mm/slub.c:5649 [inline]
__kmalloc_node_track_caller_noprof+0x4db/0x8a0 mm/slub.c:5759
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:601
__alloc_skb+0x166/0x380 net/core/skbuff.c:670
alloc_skb include/linux/skbuff.h:1383 [inline]
alloc_skb_with_frags+0xe0/0x860 net/core/skbuff.c:6671
sock_alloc_send_pskb+0x7f9/0x980 net/core/sock.c:2965
unix_dgram_sendmsg+0x3e9/0x17f0 net/unix/af_unix.c:2153
unix_seqpacket_sendmsg+0x12a/0x1c0 net/unix/af_unix.c:2556
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
sock_write_iter+0x566/0x610 net/socket.c:1195
do_iter_readv_writev+0x662/0x9e0 fs/read_write.c:827
page last free pid 5184 tgid 5184 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
__free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:352
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4978 [inline]
slab_alloc_node mm/slub.c:5288 [inline]
__kmalloc_cache_noprof+0x274/0x780 mm/slub.c:5766
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
kernfs_iop_get_link fs/kernfs/symlink.c:137 [inline]
kernfs_iop_get_link+0x65/0x1670 fs/kernfs/symlink.c:128
vfs_readlink+0x213/0x440 fs/namei.c:5461
do_readlinkat+0x24a/0x3a0 fs/stat.c:590
__do_sys_readlink fs/stat.c:613 [inline]
__se_sys_readlink fs/stat.c:610 [inline]
__x64_sys_readlink+0x78/0xc0 fs/stat.c:610
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88807be9be80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88807be9bf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807be9bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88807be9c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88807be9c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: e8 ba f3 0e 00 call 0xef3bf
5: 65 8b 1d 9b fd f3 11 mov %gs:0x11f3fd9b(%rip),%ebx # 0x11f3fda7
c: 31 ff xor %edi,%edi
e: 89 de mov %ebx,%esi
10: e8 ea ee 0e 00 call 0xeeeff
15: 85 db test %ebx,%ebx
17: 0f 84 5f 01 00 00 je 0x17c
1d: e8 9d f3 0e 00 call 0xef3bf
22: 9c pushf
23: 5b pop %rbx
24: 81 e3 00 02 00 00 and $0x200,%ebx
* 2a: fa cli <-- trapping instruction
2b: 31 ff xor %edi,%edi
2d: 48 89 de mov %rbx,%rsi
30: e8 fa ee 0e 00 call 0xeef2f
35: 48 85 db test %rbx,%rbx
38: 0f 85 69 01 00 00 jne 0x1a7
3e: e8 .byte 0xe8
3f: 7c .byte 0x7c