==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948
Read of size 1 at addr ffff888112f6bfff by task syz.4.4376/23911
CPU: 0 UID: 0 PID: 23911 Comm: syz.4.4376 Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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+0x208/0x8d0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xfa/0x160 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+0x90/0xb0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:finish_task_switch.isra.0+0x1e9/0x9e0 kernel/sched/core.c:5193
Code: 0f 85 5f 07 00 00 8b 0d 79 c2 51 09 85 c9 0f 85 b9 02 00 00 48 89 df e8 c5 ec f7 05 e8 40 10 37 00 fb 65 48 8b 1d 1f cc 48 0b <48> 8d bb 50 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffc90015c67d40 EFLAGS: 00000202
RAX: 000000000000090b RBX: ffff888106b29d00 RCX: ffffffff8186432f
RDX: 0000000000000000 RSI: ffffffff88c887eb RDI: ffffffff878979c0
RBP: ffffc90015c67d80 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff8aa0e9d7 R11: 0000000000000001 R12: ffff888138891d00
R13: 0000000000000000 R14: ffff8881f5838918 R15: ffff8881f5839418
context_switch kernel/sched/core.c:5328 [inline]
__schedule+0x1304/0x3b80 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
exit_to_user_mode_loop+0x5c/0xe0 kernel/entry/common.c:31
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x40f/0x4d0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f40b0eaf749
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:00007ffda5b58988 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f40b1105fa8 RCX: 00007f40b0eaf749
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f40b1105fa8
RBP: 0000000000000000 R08: 0000000000000001 R09: 00000007a5b58c7f
R10: 00007f40b1105fa0 R11: 0000000000000246 R12: 00007f40b1105fac
R13: 00007f40b1105fa0 R14: 0000000000001d8e R15: 0000000000000004
Allocated by task 5226:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
unpoison_slab_object mm/kasan/common.c:342 [inline]
__kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:368
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4970 [inline]
slab_alloc_node mm/slub.c:5280 [inline]
kmem_cache_alloc_node_noprof+0x26a/0x6e0 mm/slub.c:5332
kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:579
__alloc_skb+0x166/0x380 net/core/skbuff.c:670
alloc_skb include/linux/skbuff.h:1383 [inline]
netlink_alloc_large_skb+0x69/0x140 net/netlink/af_netlink.c:1186
netlink_sendmsg+0x698/0xdd0 net/netlink/af_netlink.c:1871
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2630
___sys_sendmsg+0x134/0x1d0 net/socket.c:2684
__sys_sendmsg+0x16d/0x220 net/socket.c:2716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 5226:
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+0x43/0x70 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2539 [inline]
slab_free mm/slub.c:6630 [inline]
kmem_cache_free+0x2a4/0x660 mm/slub.c:6740
skb_kfree_head net/core/skbuff.c:1046 [inline]
skb_kfree_head net/core/skbuff.c:1043 [inline]
skb_free_head+0x1b7/0x210 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
netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
netlink_unicast+0x5b2/0x870 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2630
___sys_sendmsg+0x134/0x1d0 net/socket.c:2684
__sys_sendmsg+0x16d/0x220 net/socket.c:2716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff888112f6ba80
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 [ffff888112f6ba80, ffff888112f6bd40)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x112f68
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff8881022dca00 ffffea0004d15e00 dead000000000004
raw: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000
head: 0200000000000040 ffff8881022dca00 ffffea0004d15e00 dead000000000004
head: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000
head: 0200000000000002 ffffea00044bda01 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 2855, tgid 2855 (udevd), ts 1560013407795, free_ts 1543883682231
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850
prep_new_page mm/page_alloc.c:1858 [inline]
get_page_from_freelist+0x1003/0x2dc0 mm/page_alloc.c:3884
__alloc_frozen_pages_noprof+0x259/0x21f0 mm/page_alloc.c:5183
alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2416
alloc_slab_page mm/slub.c:3055 [inline]
allocate_slab mm/slub.c:3228 [inline]
new_slab+0x24a/0x360 mm/slub.c:3282
___slab_alloc+0xdb7/0x1a70 mm/slub.c:4651
__slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4770
__slab_alloc_node mm/slub.c:4846 [inline]
slab_alloc_node mm/slub.c:5268 [inline]
kmem_cache_alloc_node_noprof+0x362/0x6e0 mm/slub.c:5332
kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:579
__alloc_skb+0x166/0x380 net/core/skbuff.c:670
alloc_skb include/linux/skbuff.h:1383 [inline]
netlink_alloc_large_skb+0x69/0x140 net/netlink/af_netlink.c:1186
netlink_sendmsg+0x698/0xdd0 net/netlink/af_netlink.c:1871
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2630
___sys_sendmsg+0x134/0x1d0 net/socket.c:2684
__sys_sendmsg+0x16d/0x220 net/socket.c:2716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94
page last free pid 22 tgid 22 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
__free_frozen_pages+0x78f/0x1000 mm/page_alloc.c:2906
pagetable_free include/linux/mm.h:2997 [inline]
pagetable_dtor_free include/linux/mm.h:3100 [inline]
__tlb_remove_table include/asm-generic/tlb.h:220 [inline]
__tlb_remove_table_free mm/mmu_gather.c:227 [inline]
tlb_remove_table_rcu+0x121/0x320 mm/mmu_gather.c:290
rcu_do_batch kernel/rcu/tree.c:2605 [inline]
rcu_core+0x79c/0x1530 kernel/rcu/tree.c:2861
handle_softirqs+0x208/0x8d0 kernel/softirq.c:622
run_ksoftirqd kernel/softirq.c:1063 [inline]
run_ksoftirqd+0x3a/0x60 kernel/softirq.c:1055
smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:160
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56d/0x700 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Memory state around the buggy address:
ffff888112f6be80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888112f6bf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888112f6bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff888112f6c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888112f6c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: 0f 85 5f 07 00 00 jne 0x765
6: 8b 0d 79 c2 51 09 mov 0x951c279(%rip),%ecx # 0x951c285
c: 85 c9 test %ecx,%ecx
e: 0f 85 b9 02 00 00 jne 0x2cd
14: 48 89 df mov %rbx,%rdi
17: e8 c5 ec f7 05 call 0x5f7ece1
1c: e8 40 10 37 00 call 0x371061
21: fb sti
22: 65 48 8b 1d 1f cc 48 mov %gs:0xb48cc1f(%rip),%rbx # 0xb48cc49
29: 0b
* 2a: 48 8d bb 50 15 00 00 lea 0x1550(%rbx),%rdi <-- trapping instruction
31: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
38: fc ff df
3b: 48 89 fa mov %rdi,%rdx
3e: 48 rex.W
3f: c1 .byte 0xc1