==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x101c/0x1090 drivers/hid/hid-mcp2221.c:964
Read of size 1 at addr ffff88804e8c7fff by task udevd/6475
CPU: 0 UID: 0 PID: 6475 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
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+0x101c/0x1090 drivers/hid/hid-mcp2221.c:964
__hid_input_report.constprop.0+0x319/0x470 drivers/hid/hid-core.c:2168
hid_irq_in+0x55d/0x710 drivers/hid/usbhid/hid-core.c:287
__usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657
usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
dummy_timer+0xda1/0x36c0 drivers/usb/gadget/udc/dummy_hcd.c:2005
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2113
handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__orc_find+0x97/0xf0 arch/x86/kernel/unwind_orc.c:110
Code: b6 34 0a 48 89 da 83 e2 07 83 c2 03 40 38 f2 7c 05 40 84 f6 75 4b 48 63 13 48 01 da 49 39 d5 73 af 4c 8d 63 fc 49 39 ec 73 b2 <4d> 29 f7 49 c1 ff 02 4b 8d 14 7f 48 8d 04 50 48 83 c4 08 5b 5d 41
RSP: 0018:ffffc90003237538 EFLAGS: 00000297
RAX: ffffffff925831e2 RBX: ffffffff919dd770 RCX: dffffc0000000000
RDX: ffffffff89813872 RSI: 0000000000000000 RDI: ffffffff919dd770
RBP: ffffffff919dd774 R08: ffffffff925831e8 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000088139 R12: ffffffff919dd770
R13: ffffffff898139e9 R14: ffffffff919dd770 R15: ffffffff919dd770
orc_find arch/x86/kernel/unwind_orc.c:238 [inline]
unwind_next_frame+0x2ec/0x2090 arch/x86/kernel/unwind_orc.c:510
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
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:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2705 [inline]
slab_free mm/slub.c:6405 [inline]
kmem_cache_free+0x127/0x6b0 mm/slub.c:6532
kfree_skbmem+0x19a/0x210 net/core/skbuff.c:1139
__kfree_skb net/core/skbuff.c:1206 [inline]
consume_skb net/core/skbuff.c:1439 [inline]
consume_skb+0xd1/0x110 net/core/skbuff.c:1433
netlink_recvmsg+0x5b9/0xa90 net/netlink/af_netlink.c:1978
sock_recvmsg_nosec net/socket.c:1126 [inline]
sock_recvmsg+0x1d5/0x220 net/socket.c:1148
____sys_recvmsg+0x21e/0x670 net/socket.c:2904
___sys_recvmsg+0x16a/0x1a0 net/socket.c:2946
__sys_recvmsg net/socket.c:2979 [inline]
__do_sys_recvmsg net/socket.c:2985 [inline]
__se_sys_recvmsg net/socket.c:2982 [inline]
__x64_sys_recvmsg+0x19a/0x260 net/socket.c:2982
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f838d6a7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffcc9c45600 EFLAGS: 00000202 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007f838de45880 RCX: 00007f838d6a7407
RDX: 0000000000000000 RSI: 00007ffcc9c45690 RDI: 000000000000000c
RBP: 00005601203de2c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000560120652c70
R13: 00007ffcc9c45750 R14: 00007ffcc9c4569c R15: 0000000000000000
Allocated by task 6329:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4612 [inline]
slab_alloc_node mm/slub.c:4945 [inline]
kmem_cache_alloc_noprof+0x26b/0x6a0 mm/slub.c:4959
avc_alloc_node+0x24/0x670 security/selinux/avc.c:498
avc_update_node.isra.0+0x48/0xb90 security/selinux/avc.c:841
avc_denied+0x141/0x190 security/selinux/avc.c:1007
avc_has_perm_noaudit+0x2fc/0x3b0 security/selinux/avc.c:1168
cred_has_capability.isra.0+0x171/0x300 security/selinux/hooks.c:1666
security_capable+0x10d/0x260 security/security.c:660
ns_capable_common kernel/capability.c:342 [inline]
ns_capable kernel/capability.c:363 [inline]
capable+0x72/0xf0 kernel/capability.c:416
audit_set_loginuid_perm kernel/audit.c:2675 [inline]
audit_set_loginuid+0x156/0x7f0 kernel/audit.c:2730
proc_loginuid_write+0x2ac/0x550 fs/proc/base.c:1348
do_loop_readv_writev fs/read_write.c:851 [inline]
do_loop_readv_writev fs/read_write.c:836 [inline]
vfs_writev+0x5ed/0xdd0 fs/read_write.c:1060
do_pwritev+0x1ac/0x270 fs/read_write.c:1154
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88804e8c7f70
which belongs to the cache avc_node of size 72
The buggy address is located 71 bytes to the right of
allocated 72-byte region [ffff88804e8c7f70, ffff88804e8c7fb8)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88804e8c7b60 pfn:0x4e8c7
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801d2da3c0 ffffea00007ba050 ffffea00013a11d0
raw: ffff88804e8c7b60 000000080027001b 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 27252, tgid 27251 (syz.3.7312), ts 430661735845, free_ts 430661612379
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
prep_new_page mm/page_alloc.c:1867 [inline]
get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
alloc_slab_page mm/slub.c:3294 [inline]
allocate_slab mm/slub.c:3408 [inline]
new_slab+0xa2/0x650 mm/slub.c:3454
refill_objects+0xe3/0x410 mm/slub.c:7338
refill_sheaf mm/slub.c:2832 [inline]
__pcs_replace_empty_main+0x376/0x680 mm/slub.c:4703
alloc_from_pcs mm/slub.c:4801 [inline]
slab_alloc_node mm/slub.c:4933 [inline]
kmem_cache_alloc_noprof+0x46e/0x6a0 mm/slub.c:4959
avc_alloc_node+0x24/0x670 security/selinux/avc.c:498
avc_insert security/selinux/avc.c:618 [inline]
avc_compute_av+0x101/0x820 security/selinux/avc.c:993
avc_perm_nonode+0xb1/0x180 security/selinux/avc.c:1117
avc_has_perm_noaudit+0x2d4/0x3b0 security/selinux/avc.c:1160
avc_has_perm+0xbd/0x1e0 security/selinux/avc.c:1195
superblock_has_perm security/selinux/hooks.c:1998 [inline]
selinux_sb_kern_mount+0x1b8/0x260 security/selinux/hooks.c:2792
security_sb_kern_mount+0x87/0x1e0 security/security.c:1037
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3841 [inline]
path_mount+0x86d/0x23d0 fs/namespace.c:4161
do_mount fs/namespace.c:4174 [inline]
__do_sys_mount fs/namespace.c:4390 [inline]
__se_sys_mount fs/namespace.c:4367 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4367
page last free pid 27252 tgid 27251 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
selinux_genfs_get_sid security/selinux/hooks.c:1364 [inline]
inode_doinit_with_dentry+0x1058/0x1320 security/selinux/hooks.c:1563
sb_finish_set_opts+0x3fc/0x850 security/selinux/hooks.c:606
selinux_set_mnt_opts+0x1222/0x18d0 security/selinux/hooks.c:879
security_sb_set_mnt_opts+0xc0/0x140 security/security.c:1140
vfs_get_tree+0x1ac/0x320 fs/super.c:1719
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3765 [inline]
do_new_mount fs/namespace.c:3841 [inline]
path_mount+0x7d0/0x23d0 fs/namespace.c:4161
do_mount fs/namespace.c:4174 [inline]
__do_sys_mount fs/namespace.c:4390 [inline]
__se_sys_mount fs/namespace.c:4367 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4367
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88804e8c7e80: fc fc fc fc fa fb fb fb fb fb fb fb fb fc fc fc
ffff88804e8c7f00: fc 00 00 00 00 00 00 00 00 00 fc fc fc fc 00 00
>ffff88804e8c7f80: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
^
ffff88804e8c8000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88804e8c8080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: b6 34 mov $0x34,%dh
2: 0a 48 89 or -0x77(%rax),%cl
5: da 83 e2 07 83 c2 fiaddl -0x3d7cf81e(%rbx)
b: 03 40 38 add 0x38(%rax),%eax
e: f2 7c 05 bnd jl 0x16
11: 40 84 f6 test %sil,%sil
14: 75 4b jne 0x61
16: 48 63 13 movslq (%rbx),%rdx
19: 48 01 da add %rbx,%rdx
1c: 49 39 d5 cmp %rdx,%r13
1f: 73 af jae 0xffffffd0
21: 4c 8d 63 fc lea -0x4(%rbx),%r12
25: 49 39 ec cmp %rbp,%r12
28: 73 b2 jae 0xffffffdc
* 2a: 4d 29 f7 sub %r14,%r15 <-- trapping instruction
2d: 49 c1 ff 02 sar $0x2,%r15
31: 4b 8d 14 7f lea (%r15,%r15,2),%rdx
35: 48 8d 04 50 lea (%rax,%rdx,2),%rax
39: 48 83 c4 08 add $0x8,%rsp
3d: 5b pop %rbx
3e: 5d pop %rbp
3f: 41 rex.B