==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0xf94/0x1030 drivers/hid/hid-mcp2221.c:944
Read of size 1 at addr ffff88804738bfff by task kworker/1:4/5922
CPU: 1 UID: 0 PID: 5922 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: usb_hub_wq hub_event
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:__rcu_read_lock+0xa3/0xf0 kernel/rcu/tree_plugin.h:416
Code: 84 d2 75 61 48 b8 00 00 00 00 00 fc ff df 89 9d 44 04 00 00 65 48 8b 1d 43 d2 35 12 48 8d bb 44 04 00 00 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1f 8b
RSP: 0018:ffffc900044ee150 EFLAGS: 00000a07
RAX: dffffc0000000000 RBX: ffff888027588000 RCX: ffffc900044ee12c
RDX: 1ffff11004eb1088 RSI: ffffffff87422270 RDI: ffff888027588444
RBP: ffff888027588000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000007 R11: 000000000007ea78 R12: ffffffff81a6db90
R13: ffffc900044ee1d8 R14: 0000000000000000 R15: ffff888027588000
rcu_read_lock include/linux/rcupdate.h:839 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xae/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4365 [inline]
__kmalloc_node_track_caller_noprof+0x221/0x510 mm/slub.c:4384
__kmemdup_nul mm/util.c:64 [inline]
kstrdup+0x53/0x100 mm/util.c:84
kstrdup_const+0x63/0x80 mm/util.c:104
__kernfs_new_node+0x9b/0x8e0 fs/kernfs/dir.c:633
kernfs_new_node+0x13c/0x1e0 fs/kernfs/dir.c:713
kernfs_create_link+0xcc/0x240 fs/kernfs/symlink.c:39
sysfs_do_create_link_sd+0x90/0x140 fs/sysfs/symlink.c:44
sysfs_do_create_link fs/sysfs/symlink.c:80 [inline]
sysfs_create_link+0x61/0xc0 fs/sysfs/symlink.c:92
device_add_class_symlinks drivers/base/core.c:3448 [inline]
device_add+0x62c/0x1aa0 drivers/base/core.c:3640
cdev_device_add+0xc2/0x1e0 fs/char_dev.c:556
i2cdev_attach_adapter+0x359/0x4c0 drivers/i2c/i2c-dev.c:691
i2cdev_notifier_call+0x65/0x80 drivers/i2c/i2c-dev.c:729
notifier_call_chain+0xbc/0x410 kernel/notifier.c:85
blocking_notifier_call_chain kernel/notifier.c:380 [inline]
blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368
bus_notify+0x56/0x70 drivers/base/bus.c:1001
device_add+0x10d3/0x1aa0 drivers/base/core.c:3669
i2c_register_adapter+0x39e/0x1370 drivers/i2c/i2c-core-base.c:1576
i2c_add_adapter drivers/i2c/i2c-core-base.c:1676 [inline]
i2c_add_adapter+0x10a/0x1b0 drivers/i2c/i2c-core-base.c:1656
devm_i2c_add_adapter+0x1b/0x90 drivers/i2c/i2c-core-base.c:1848
mcp2221_probe+0x5f1/0xc50 drivers/hid/hid-mcp2221.c:1285
__hid_device_probe drivers/hid/hid-core.c:2740 [inline]
hid_device_probe+0x360/0x720 drivers/hid/hid-core.c:2777
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
device_add+0x1148/0x1aa0 drivers/base/core.c:3689
hid_add_device+0x373/0xa60 drivers/hid/hid-core.c:2923
usbhid_probe+0xd38/0x13f0 drivers/hid/usbhid/hid-core.c:1435
usb_probe_interface+0x300/0xa40 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
device_add+0x1148/0x1aa0 drivers/base/core.c:3689
usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x3e0 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
device_add+0x1148/0x1aa0 drivers/base/core.c:3689
usb_new_device+0xd07/0x1a60 drivers/usb/core/hub.c:2694
hub_port_connect drivers/usb/core/hub.c:5566 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x2f34/0x4fe0 drivers/usb/core/hub.c:5952
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
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Allocated by task 5841:
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
napi_alloc_skb+0x3fa/0x830 net/core/skbuff.c:811
page_to_skb+0x184/0xcc0 drivers/net/virtio_net.c:889
receive_mergeable drivers/net/virtio_net.c:2496 [inline]
receive_buf+0x789/0x4460 drivers/net/virtio_net.c:2634
virtnet_receive_packets drivers/net/virtio_net.c:2992 [inline]
virtnet_receive drivers/net/virtio_net.c:3016 [inline]
virtnet_poll+0x10d4/0x3c10 drivers/net/virtio_net.c:3110
__napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7506
napi_poll net/core/dev.c:7569 [inline]
net_rx_action+0xa9f/0xfe0 net/core/dev.c:7696
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
common_interrupt+0xbf/0xe0 arch/x86/kernel/irq.c:318
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
Freed by task 5841:
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+0x4f/0x70 net/core/skbuff.c:1165
tcp_rcv_established+0xdb1/0x23f0 net/ipv4/tcp_input.c:6121
tcp_v4_do_rcv+0x5ca/0xa90 net/ipv4/tcp_ipv4.c:1926
tcp_v4_rcv+0x2ee1/0x4640 net/ipv4/tcp_ipv4.c:2368
ip_protocol_deliver_rcu+0xba/0x4c0 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x3f2/0x720 net/ipv4/ip_input.c:239
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ip_local_deliver+0x18e/0x1f0 net/ipv4/ip_input.c:260
dst_input include/net/dst.h:471 [inline]
ip_sublist_rcv_finish+0x2ce/0x660 net/ipv4/ip_input.c:585
ip_list_rcv_finish+0x552/0x720 net/ipv4/ip_input.c:634
ip_sublist_rcv net/ipv4/ip_input.c:642 [inline]
ip_list_rcv+0x335/0x450 net/ipv4/ip_input.c:676
__netif_receive_skb_list_ptype net/core/dev.c:6034 [inline]
__netif_receive_skb_list_core+0x752/0x950 net/core/dev.c:6081
__netif_receive_skb_list net/core/dev.c:6133 [inline]
netif_receive_skb_list_internal+0x752/0xdb0 net/core/dev.c:6224
gro_normal_list include/net/gro.h:532 [inline]
gro_normal_list include/net/gro.h:528 [inline]
gro_flush_normal include/net/gro.h:540 [inline]
napi_complete_done+0x23f/0x970 net/core/dev.c:6593
virtqueue_napi_complete drivers/net/virtio_net.c:766 [inline]
virtnet_poll+0x1cf0/0x3c10 drivers/net/virtio_net.c:3118
__napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7506
napi_poll net/core/dev.c:7569 [inline]
net_rx_action+0xa9f/0xfe0 net/core/dev.c:7696
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
common_interrupt+0xbf/0xe0 arch/x86/kernel/irq.c:318
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
The buggy address belongs to the object at ffff88804738ba80
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 [ffff88804738ba80, ffff88804738bd40)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x47388
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 ffff888140affc80 ffffea00010b2f00 dead000000000002
raw: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888140affc80 ffffea00010b2f00 dead000000000002
head: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea00011ce201 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 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9302, tgid 9296 (syz.1.888), ts 310739887343, free_ts 310290856017
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
skb_copy+0x1c9/0x3a0 net/core/skbuff.c:2124
mac80211_hwsim_tx_frame_no_nl.isra.0+0xb6e/0x13c0 drivers/net/wireless/virtual/mac80211_hwsim.c:1871
mac80211_hwsim_tx_frame+0x1f1/0x2a0 drivers/net/wireless/virtual/mac80211_hwsim.c:2222
__mac80211_hwsim_beacon_tx drivers/net/wireless/virtual/mac80211_hwsim.c:2239 [inline]
mac80211_hwsim_beacon_tx+0x592/0xa40 drivers/net/wireless/virtual/mac80211_hwsim.c:2323
__iterate_interfaces+0x2e5/0x650 net/mac80211/util.c:761
ieee80211_iterate_active_interfaces_atomic+0x71/0x1b0 net/mac80211/util.c:797
page last free pid 9301 tgid 9295 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
btrfs_free_fs_context+0x74/0x140 fs/btrfs/super.c:2127
put_fs_context+0x155/0x600 fs/fs_context.c:524
btrfs_get_tree_subvol fs/btrfs/super.c:2103 [inline]
btrfs_get_tree+0x1576/0x26f0 fs/btrfs/super.c:2111
vfs_get_tree+0x8b/0x340 fs/super.c:1815
do_new_mount fs/namespace.c:3808 [inline]
path_mount+0x1513/0x2000 fs/namespace.c:4123
do_mount fs/namespace.c:4136 [inline]
__do_sys_mount fs/namespace.c:4347 [inline]
__se_sys_mount fs/namespace.c:4324 [inline]
__x64_sys_mount+0x28d/0x310 fs/namespace.c:4324
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
Memory state around the buggy address:
ffff88804738be80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88804738bf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88804738bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88804738c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88804738c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: 84 d2 test %dl,%dl
2: 75 61 jne 0x65
4: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
b: fc ff df
e: 89 9d 44 04 00 00 mov %ebx,0x444(%rbp)
14: 65 48 8b 1d 43 d2 35 mov %gs:0x1235d243(%rip),%rbx # 0x1235d25f
1b: 12
1c: 48 8d bb 44 04 00 00 lea 0x444(%rbx),%rdi
23: 48 89 fa mov %rdi,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx <-- trapping instruction
2e: 48 89 f8 mov %rdi,%rax
31: 83 e0 07 and $0x7,%eax
34: 83 c0 03 add $0x3,%eax
37: 38 d0 cmp %dl,%al
39: 7c 04 jl 0x3f
3b: 84 d2 test %dl,%dl
3d: 75 1f jne 0x5e
3f: 8b .byte 0x8b