==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1062/0x1240 drivers/hid/hid-mcp2221.c:858
Read of size 1 at addr ffff88805bd17fff by task syz.6.1640/11139
CPU: 0 PID: 11139 Comm: syz.6.1640 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0xa8/0x210 mm/kasan/report.c:468
kasan_report+0x117/0x150 mm/kasan/report.c:581
mcp2221_raw_event+0x1062/0x1240 drivers/hid/hid-mcp2221.c:858
hid_input_report+0x400/0x510 drivers/hid/hid-core.c:2103
hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650
dummy_timer+0x8de/0x3320 drivers/usb/gadget/udc/dummy_hcd.c:2003
__run_hrtimer kernel/time/hrtimer.c:1754 [inline]
__hrtimer_run_queues+0x520/0xc40 kernel/time/hrtimer.c:1818
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1835
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 2b 88 ca f6 65 8b 05 bc b0 71 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc900034878a0 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: 83cfb2caedab0900
RDX: dffffc0000000000 RSI: ffffffff8acacbe0 RDI: 0000000000000001
RBP: ffffc90003487938 R08: ffffffff8e8b666f R09: 1ffffffff1d16ccd
R10: dffffc0000000000 R11: fffffbfff1d16cce R12: dffffc0000000000
R13: ffff8880250400c0 R14: ffff888025040000 R15: 1ffff92000690f14
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
dummy_queue+0x577/0x8e0 drivers/usb/gadget/udc/dummy_hcd.c:748
usb_ep_queue+0xea/0x350 drivers/usb/gadget/udc/core.c:303
raw_process_ep_io+0x5f8/0xc80 drivers/usb/gadget/legacy/raw_gadget.c:1068
raw_ioctl_ep_write drivers/usb/gadget/legacy/raw_gadget.c:1108 [inline]
raw_ioctl+0x2514/0x3dd0 drivers/usb/gadget/legacy/raw_gadget.c:1280
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fecf799caeb
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007fecf884af60 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fecf799caeb
RDX: 00007fecf884afe0 RSI: 0000000040085507 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007fecf7d40320 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 00002000000006c0
R13: 0000000000000000 R14: 00007fecf7c15fa0 R15: 00007ffd836f2588
Allocated by task 11033:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
____kasan_kmalloc mm/kasan/common.c:375 [inline]
__kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384
kmalloc include/linux/slab.h:600 [inline]
kzalloc include/linux/slab.h:721 [inline]
kernfs_iop_get_link+0x66/0x660 fs/kernfs/symlink.c:135
vfs_readlink+0x168/0x350 fs/namei.c:5129
do_readlinkat+0x255/0x490 fs/stat.c:506
__do_sys_readlink fs/stat.c:527 [inline]
__se_sys_readlink fs/stat.c:524 [inline]
__x64_sys_readlink+0x7f/0x90 fs/stat.c:524
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Freed by task 11033:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
__kmem_cache_free+0xba/0x1e0 mm/slub.c:3843
do_delayed_call include/linux/delayed_call.h:28 [inline]
vfs_readlink+0x1aa/0x350 fs/namei.c:5134
do_readlinkat+0x255/0x490 fs/stat.c:506
__do_sys_readlink fs/stat.c:527 [inline]
__se_sys_readlink fs/stat.c:524 [inline]
__x64_sys_readlink+0x7f/0x90 fs/stat.c:524
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
The buggy address belongs to the object at ffff88805bd16000
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 [ffff88805bd16000, ffff88805bd17000)
The buggy address belongs to the physical page:
page:ffffea00016f4400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5bd10
head:ffffea00016f4400 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888017c42140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5779, tgid 5779 (syz-executor), ts 195324099483, free_ts 182256219857
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581
prep_new_page mm/page_alloc.c:1588 [inline]
get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220
__alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500
alloc_slab_page+0x5d/0x160 mm/slub.c:1881
allocate_slab mm/slub.c:2028 [inline]
new_slab+0x87/0x2d0 mm/slub.c:2081
___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253
__slab_alloc mm/slub.c:3339 [inline]
__slab_alloc_node mm/slub.c:3392 [inline]
slab_alloc_node mm/slub.c:3485 [inline]
__kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc+0xa4/0x230 mm/slab_common.c:1020
kmalloc include/linux/slab.h:604 [inline]
tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_number_perm+0x248/0x620 security/tomoyo/file.c:723
security_file_ioctl+0x70/0xa0 security/security.c:2648
__do_sys_ioctl fs/ioctl.c:865 [inline]
__se_sys_ioctl+0x48/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1181 [inline]
free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365
free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458
discard_slab mm/slub.c:2127 [inline]
__unfreeze_partials+0x1cf/0x210 mm/slub.c:2667
put_cpu_partial+0x17c/0x250 mm/slub.c:2743
__slab_free+0x319/0x400 mm/slub.c:3700
qlink_free mm/kasan/quarantine.c:166 [inline]
qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185
kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767
slab_alloc_node mm/slub.c:3495 [inline]
slab_alloc mm/slub.c:3503 [inline]
__kmem_cache_alloc_lru mm/slub.c:3510 [inline]
kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519
getname_flags+0xbb/0x500 fs/namei.c:140
user_path_at_empty+0x2c/0x60 fs/namei.c:2916
do_readlinkat+0xdd/0x490 fs/stat.c:494
__do_sys_readlink fs/stat.c:527 [inline]
__se_sys_readlink fs/stat.c:524 [inline]
__x64_sys_readlink+0x7f/0x90 fs/stat.c:524
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Memory state around the buggy address:
ffff88805bd17e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88805bd17f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88805bd17f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88805bd18000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88805bd18080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: c7 44 24 20 00 00 00 movl $0x0,0x20(%rsp)
7: 00
8: 9c pushf
9: 8f 44 24 20 pop 0x20(%rsp)
d: f7 44 24 20 00 02 00 testl $0x200,0x20(%rsp)
14: 00
15: 41 c6 04 07 f8 movb $0xf8,(%r15,%rax,1)
1a: 75 4b jne 0x67
1c: f7 c3 00 02 00 00 test $0x200,%ebx
22: 74 01 je 0x25
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 2b 88 ca f6 call 0xf6ca885a <-- trapping instruction
2f: 65 8b 05 bc b0 71 75 mov %gs:0x7571b0bc(%rip),%eax # 0x7571b0f2
36: 85 c0 test %eax,%eax
38: 74 3c je 0x76
3a: 48 rex.W
3b: c7 .byte 0xc7
3c: 04 24 add $0x24,%al
3e: 0e (bad)
3f: 36 ss