==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0xf94/0x1030 drivers/hid/hid-mcp2221.c:944
Read of size 1 at addr ffff888046c63fff by task syz.0.702/9752
CPU: 1 UID: 0 PID: 9752 Comm: syz.0.702 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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+0xf94/0x1030 drivers/hid/hid-mcp2221.c:944
__hid_input_report.constprop.0+0x311/0x450 drivers/hid/hid-core.c:2130
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+0x1814/0x3a30 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825
hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842
handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__sanitizer_cov_trace_pc+0x56/0x70 kernel/kcov.c:222
Code: 00 f0 00 75 35 8b 82 3c 16 00 00 85 c0 74 2b 8b 82 18 16 00 00 83 f8 02 75 20 48 8b 8a 20 16 00 00 8b 92 1c 16 00 00 48 8b 01 <48> 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 c3 cc cc cc cc 0f
RSP: 0018:ffffc90003a8f868 EFLAGS: 00000246
RAX: 000000000007ffff RBX: ffff8880582d5d80 RCX: ffffc9000dc37000
RDX: 0000000000080000 RSI: ffffffff8a3990cd RDI: 0000000000000005
RBP: 00000000ffffffff R08: 0000000000000005 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8880582d62f0
R13: 0000000000000000 R14: 0000000000000000 R15: ffff888075214280
__unix_dgram_recvmsg+0x99d/0xc30 net/unix/af_unix.c:2675
unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2700
sock_recvmsg_nosec net/socket.c:1065 [inline]
____sys_recvmsg+0x5f6/0x6b0 net/socket.c:2832
___sys_recvmsg+0x114/0x1a0 net/socket.c:2876
do_recvmmsg+0x2fe/0x750 net/socket.c:2971
__sys_recvmmsg net/socket.c:3045 [inline]
__do_sys_recvmmsg net/socket.c:3068 [inline]
__se_sys_recvmmsg net/socket.c:3061 [inline]
__x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3061
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faf3a38ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007faf3b19e038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007faf3a5b6090 RCX: 00007faf3a38ebe9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006
RBP: 00007faf3a411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faf3a5b6128 R14: 00007faf3a5b6090 R15: 00007ffdf4498bc8
Allocated by task 5514:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:330 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:356
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4180 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
kmem_cache_alloc_node_noprof+0x1d5/0x3b0 mm/slub.c:4281
kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:578
__alloc_skb+0x166/0x380 net/core/skbuff.c:669
alloc_skb include/linux/skbuff.h:1336 [inline]
nlmsg_new include/net/netlink.h:1055 [inline]
netlink_ack+0x15d/0xb80 net/netlink/af_netlink.c:2489
netlink_rcv_skb+0x332/0x420 net/netlink/af_netlink.c:2558
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x5a7/0x870 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg net/socket.c:729 [inline]
____sys_sendmsg+0xa95/0xc70 net/socket.c:2614
___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
__sys_sendmsg+0x16d/0x220 net/socket.c:2700
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 5514:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:243 [inline]
__kasan_slab_free+0x60/0x70 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2417 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4782
skb_kfree_head net/core/skbuff.c:1045 [inline]
skb_kfree_head net/core/skbuff.c:1042 [inline]
skb_free_head+0x1b7/0x210 net/core/skbuff.c:1059
skb_release_data+0x795/0x9e0 net/core/skbuff.c:1086
skb_release_all net/core/skbuff.c:1151 [inline]
__kfree_skb net/core/skbuff.c:1165 [inline]
consume_skb net/core/skbuff.c:1397 [inline]
consume_skb+0xbf/0x100 net/core/skbuff.c:1391
netlink_recvmsg+0x5b9/0xa90 net/netlink/af_netlink.c:1974
sock_recvmsg_nosec net/socket.c:1065 [inline]
sock_recvmsg+0x1f9/0x250 net/socket.c:1087
____sys_recvmsg+0x218/0x6b0 net/socket.c:2834
___sys_recvmsg+0x114/0x1a0 net/socket.c:2876
__sys_recvmsg+0x16a/0x220 net/socket.c:2909
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff888046c63a80
which belongs to the cache skbuff_small_head of size 704
The buggy address is located 703 bytes to the right of
allocated 704-byte region [ffff888046c63a80, ffff888046c63d40)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x46c60
head: order:2 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 ffff88801f2ddc80 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801f2ddc80 dead000000000122 0000000000000000
head: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00011b1801 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 5514, tgid 5514 (dhcpcd), ts 363267546760, free_ts 336584433831
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851
prep_new_page mm/page_alloc.c:1859 [inline]
get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858
__alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
alloc_slab_page mm/slub.c:2487 [inline]
allocate_slab mm/slub.c:2655 [inline]
new_slab+0x247/0x330 mm/slub.c:2709
___slab_alloc+0xcf2/0x1740 mm/slub.c:3891
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981
__slab_alloc_node mm/slub.c:4056 [inline]
slab_alloc_node mm/slub.c:4217 [inline]
kmem_cache_alloc_node_noprof+0xf5/0x3b0 mm/slub.c:4281
kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:578
__alloc_skb+0x166/0x380 net/core/skbuff.c:669
alloc_skb include/linux/skbuff.h:1336 [inline]
netlink_alloc_large_skb+0x69/0x130 net/netlink/af_netlink.c:1186
netlink_sendmsg+0x6a1/0xdd0 net/netlink/af_netlink.c:1871
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg net/socket.c:729 [inline]
____sys_sendmsg+0xa95/0xc70 net/socket.c:2614
___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
__sys_sendmsg+0x16d/0x220 net/socket.c:2700
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
page last free pid 6007 tgid 6007 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
__free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895
discard_slab mm/slub.c:2753 [inline]
__put_partials+0x165/0x1c0 mm/slub.c:3218
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:340
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4180 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
kmem_cache_alloc_lru_noprof+0x1d0/0x3b0 mm/slub.c:4248
sock_alloc_inode+0x25/0x1c0 net/socket.c:309
alloc_inode+0x64/0x240 fs/inode.c:346
new_inode_pseudo include/linux/fs.h:3391 [inline]
sock_alloc+0x40/0x280 net/socket.c:624
__sock_create+0xc1/0x8d0 net/socket.c:1553
rds_tcp_conn_path_connect+0x2d0/0x7f0 net/rds/tcp_connect.c:115
rds_connect_worker+0x1ac/0x2c0 net/rds/threads.c:176
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
Memory state around the buggy address:
ffff888046c63e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888046c63f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888046c63f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff888046c64000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888046c64080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: 00 f0 add %dh,%al
2: 00 75 35 add %dh,0x35(%rbp)
5: 8b 82 3c 16 00 00 mov 0x163c(%rdx),%eax
b: 85 c0 test %eax,%eax
d: 74 2b je 0x3a
f: 8b 82 18 16 00 00 mov 0x1618(%rdx),%eax
15: 83 f8 02 cmp $0x2,%eax
18: 75 20 jne 0x3a
1a: 48 8b 8a 20 16 00 00 mov 0x1620(%rdx),%rcx
21: 8b 92 1c 16 00 00 mov 0x161c(%rdx),%edx
27: 48 8b 01 mov (%rcx),%rax
* 2a: 48 83 c0 01 add $0x1,%rax <-- trapping instruction
2e: 48 39 d0 cmp %rdx,%rax
31: 73 07 jae 0x3a
33: 48 89 01 mov %rax,(%rcx)
36: 48 89 34 c1 mov %rsi,(%rcx,%rax,8)
3a: c3 ret
3b: cc int3
3c: cc int3
3d: cc int3
3e: cc int3
3f: 0f .byte 0xf