==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948
Read of size 1 at addr ffff888050ed7fff by task syz.4.656/8329
CPU: 1 UID: 0 PID: 8329 Comm: syz.4.656 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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:2130
hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:286
__usb_hcd_giveback_urb+0x388/0x610 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+0x202/0xad0 kernel/time/hrtimer.c:1825
hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842
handle_softirqs+0x219/0x8e0 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:finish_task_switch.isra.0+0x22a/0xc10 kernel/sched/core.c:5225
Code: fb 09 00 00 44 8b 05 b9 8c 22 0f 45 85 c0 0f 85 be 01 00 00 4c 89 e7 e8 a4 f6 ff ff e8 af 69 3a 00 fb 65 48 8b 1d 5e c5 4d 12 <48> 8d bb 18 16 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffc900101071e0 EFLAGS: 00000206
RAX: 0000000000004699 RBX: ffff8880316c0000 RCX: 0000000000000007
RDX: 0000000000000000 RSI: ffffffff8de52d29 RDI: ffffffff8c163380
RBP: ffffc90010107228 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90ab7597 R11: 0000000000000000 R12: ffff8880b853a300
R13: ffff8880546b0000 R14: ffff8880b843a300 R15: ffff8880b853b170
context_switch kernel/sched/core.c:5360 [inline]
__schedule+0x1198/0x5de0 kernel/sched/core.c:6961
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7145
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
wp_page_copy mm/memory.c:3653 [inline]
do_wp_page+0x177b/0x4f00 mm/memory.c:4013
handle_pte_fault mm/memory.c:6068 [inline]
__handle_mm_fault+0x1b2d/0x2a50 mm/memory.c:6195
handle_mm_fault+0x589/0xd10 mm/memory.c:6364
do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:rep_movs_alternative+0x4a/0x90 arch/x86/lib/copy_user_64.S:74
Code: cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08 73 e8 eb c5 a4 c3 cc cc cc cc 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48
RSP: 0018:ffffc90010107948 EFLAGS: 00050206
RAX: 0000000000000001 RBX: 0000000000001000 RCX: 0000000000000e80
RDX: 0000000000000000 RSI: ffff888013dad180 RDI: 00002000000e0000
RBP: 0000000000001000 R08: 0000000000000000 R09: ffffed10027b5bff
R10: ffff888013dadfff R11: 0000000000000000 R12: 00000000000dfb80
R13: ffffc90010107d50 R14: ffff888013dad000 R15: 00002000000dfe80
copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
copy_to_user_iter lib/iov_iter.c:25 [inline]
iterate_iovec include/linux/iov_iter.h:52 [inline]
iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
iterate_and_advance include/linux/iov_iter.h:330 [inline]
_copy_to_iter+0x4eb/0x1710 lib/iov_iter.c:185
copy_page_to_iter lib/iov_iter.c:362 [inline]
copy_page_to_iter+0x12a/0x1e0 lib/iov_iter.c:349
process_vm_rw_pages mm/process_vm_access.c:45 [inline]
process_vm_rw_single_vec mm/process_vm_access.c:118 [inline]
process_vm_rw_core.constprop.0+0x5ad/0x970 mm/process_vm_access.c:216
process_vm_rw+0x2ff/0x360 mm/process_vm_access.c:284
__do_sys_process_vm_readv mm/process_vm_access.c:296 [inline]
__se_sys_process_vm_readv mm/process_vm_access.c:292 [inline]
__x64_sys_process_vm_readv+0xe2/0x1c0 mm/process_vm_access.c:292
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd115b8ec29
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:00007fd1169df038 EFLAGS: 00000246 ORIG_RAX: 0000000000000136
RAX: ffffffffffffffda RBX: 00007fd115dd6090 RCX: 00007fd115b8ec29
RDX: 0000000000000002 RSI: 0000200000008400 RDI: 00000000000001e3
RBP: 00007fd115c11e41 R08: 0000000000000286 R09: 0000000000000000
R10: 0000200000008640 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd115dd6128 R14: 00007fd115dd6090 R15: 00007ffd715c9258
Allocated by task 8321:
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:4376 [inline]
__kmalloc_noprof+0x223/0x510 mm/slub.c:4388
kmalloc_noprof include/linux/slab.h:909 [inline]
tomoyo_realpath_from_path+0xc2/0x6e0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x274/0x460 security/tomoyo/file.c:822
tomoyo_path_symlink+0x97/0xe0 security/tomoyo/tomoyo.c:212
security_path_symlink+0x152/0x2e0 security/security.c:1984
do_symlinkat+0x10d/0x310 fs/namei.c:4754
__do_sys_symlinkat fs/namei.c:4772 [inline]
__se_sys_symlinkat fs/namei.c:4769 [inline]
__x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4769
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 8321:
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:2422 [inline]
slab_free mm/slub.c:4695 [inline]
kfree+0x2b4/0x4d0 mm/slub.c:4894
tomoyo_realpath_from_path+0x19f/0x6e0 security/tomoyo/realpath.c:286
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x274/0x460 security/tomoyo/file.c:822
tomoyo_path_symlink+0x97/0xe0 security/tomoyo/tomoyo.c:212
security_path_symlink+0x152/0x2e0 security/security.c:1984
do_symlinkat+0x10d/0x310 fs/namei.c:4754
__do_sys_symlinkat fs/namei.c:4772 [inline]
__se_sys_symlinkat fs/namei.c:4769 [inline]
__x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4769
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff888050ed6000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 4095 bytes to the right of
allocated 4096-byte region [ffff888050ed6000, ffff888050ed7000)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x50ed0
head: order:3 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 ffff88801b842140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b842140 dead000000000100 dead000000000122
head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea000143b401 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5852, tgid 5852 (syz-executor), ts 104992691521, free_ts 104961154267
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:2492 [inline]
allocate_slab mm/slub.c:2660 [inline]
new_slab+0x247/0x330 mm/slub.c:2714
___slab_alloc+0xcf2/0x1750 mm/slub.c:3901
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3992
__slab_alloc_node mm/slub.c:4067 [inline]
slab_alloc_node mm/slub.c:4228 [inline]
__do_kmalloc_node mm/slub.c:4375 [inline]
__kmalloc_noprof+0x2f2/0x510 mm/slub.c:4388
kmalloc_noprof include/linux/slab.h:909 [inline]
tomoyo_realpath_from_path+0xc2/0x6e0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_number_perm+0x245/0x580 security/tomoyo/file.c:723
tomoyo_path_mkdir+0x9b/0xe0 security/tomoyo/tomoyo.c:179
security_path_mkdir+0x154/0x2f0 security/security.c:1932
do_mkdirat+0x175/0x3e0 fs/namei.c:4396
__do_sys_mkdirat fs/namei.c:4416 [inline]
__se_sys_mkdirat fs/namei.c:4414 [inline]
__x64_sys_mkdirat+0x83/0xb0 fs/namei.c:4414
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5866 tgid 5866 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:2758 [inline]
__put_partials+0x165/0x1c0 mm/slub.c:3223
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:4191 [inline]
slab_alloc_node mm/slub.c:4240 [inline]
__do_kmalloc_node mm/slub.c:4375 [inline]
__kvmalloc_node_noprof+0x230/0x620 mm/slub.c:5067
seq_buf_alloc fs/seq_file.c:38 [inline]
seq_read_iter+0x826/0x12c0 fs/seq_file.c:210
kernfs_fop_read_iter+0x46c/0x610 fs/kernfs/file.c:297
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0x8bc/0xcf0 fs/read_write.c:572
ksys_read+0x12a/0x250 fs/read_write.c:715
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff888050ed7e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888050ed7f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888050ed7f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff888050ed8000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888050ed8080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: fb sti
1: 09 00 or %eax,(%rax)
3: 00 44 8b 05 add %al,0x5(%rbx,%rcx,4)
7: b9 8c 22 0f 45 mov $0x450f228c,%ecx
c: 85 c0 test %eax,%eax
e: 0f 85 be 01 00 00 jne 0x1d2
14: 4c 89 e7 mov %r12,%rdi
17: e8 a4 f6 ff ff call 0xfffff6c0
1c: e8 af 69 3a 00 call 0x3a69d0
21: fb sti
22: 65 48 8b 1d 5e c5 4d mov %gs:0x124dc55e(%rip),%rbx # 0x124dc588
29: 12
* 2a: 48 8d bb 18 16 00 00 lea 0x1618(%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