==================================================================
BUG: KASAN: slab-out-of-bounds in mcp2221_raw_event+0x1070/0x10a0 drivers/hid/hid-mcp2221.c:948
Read of size 1 at addr ffff88812e8abfff by task kworker/0:0/9
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events legacy_dvb_usb_read_remote_control
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+0x388/0x610 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+0x205/0x8d0 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:702
RIP: 0010:console_flush_all+0x9a2/0xc60 kernel/printk/printk.c:3200
Code: 00 e8 72 9f 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 d0 b5 20 00 48 85 db 0f 85 55 01 00 00 e8 52 ba 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 c7 da 80
RSP: 0018:ffffc9000009f868 EFLAGS: 00000293
RAX: ffffffff897fca98 RBX: 0000000000000000 RCX: ffffffff815d9ae0
RDX: ffff8881016f8000 RSI: ffffffff815d9aee RDI: 0000000000000007
RBP: 0000000000000001 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff897fca98
R13: ffffffff897fca40 R14: ffffc9000009f8f8 R15: dffffc0000000000
__console_flush_and_unlock kernel/printk/printk.c:3258 [inline]
console_unlock+0xd8/0x210 kernel/printk/printk.c:3298
vprintk_emit+0x3d7/0x680 kernel/printk/printk.c:2423
_printk+0xc7/0x100 kernel/printk/printk.c:2448
legacy_dvb_usb_read_remote_control+0x40b/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:124
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3263
process_scheduled_works kernel/workqueue.c:3346 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56a/0x700 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Allocated by task 2843:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
__kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:417
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5603 [inline]
__kmalloc_node_track_caller_noprof+0x343/0x850 mm/slub.c:5712
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:601
__alloc_skb+0x166/0x380 net/core/skbuff.c:670
alloc_skb include/linux/skbuff.h:1383 [inline]
alloc_skb_with_frags+0xe0/0x860 net/core/skbuff.c:6671
sock_alloc_send_pskb+0x7f9/0x980 net/core/sock.c:2965
unix_dgram_sendmsg+0x3e9/0x17f0 net/unix/af_unix.c:2153
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x4a3/0x520 net/socket.c:2244
__do_sys_sendto net/socket.c:2251 [inline]
__se_sys_sendto net/socket.c:2247 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2247
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 2836:
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:2514 [inline]
slab_free mm/slub.c:6566 [inline]
kfree+0x288/0x670 mm/slub.c:6773
skb_kfree_head net/core/skbuff.c:1048 [inline]
skb_free_head+0x114/0x210 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
__unix_dgram_recvmsg+0x779/0xc30 net/unix/af_unix.c:2683
unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2700
sock_recvmsg_nosec net/socket.c:1078 [inline]
sock_recvmsg+0x1f9/0x250 net/socket.c:1100
sock_read_iter+0x2b9/0x3b0 net/socket.c:1170
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0xa98/0xcf0 fs/read_write.c:572
ksys_read+0x1f8/0x250 fs/read_write.c:715
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 ffff88812e8abc00
which belongs to the cache kmalloc-cg-512 of size 512
The buggy address is located 511 bytes to the right of
allocated 512-byte region [ffff88812e8abc00, ffff88812e8abe00)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12e8a8
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888136724f01
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff88810004b140 ffffea00041ccb00 dead000000000002
raw: 0000000000000000 0000000000100010 00000000f5000000 ffff888136724f01
head: 0200000000000040 ffff88810004b140 ffffea00041ccb00 dead000000000002
head: 0000000000000000 0000000000100010 00000000f5000000 ffff888136724f01
head: 0200000000000002 ffffea0004ba2a01 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 8404, tgid 8404 (udevd), ts 1429084506085, free_ts 1425585587924
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:3030 [inline]
allocate_slab mm/slub.c:3203 [inline]
new_slab+0x24a/0x360 mm/slub.c:3257
___slab_alloc+0xdb7/0x1a70 mm/slub.c:4627
__slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4746
__slab_alloc_node mm/slub.c:4822 [inline]
slab_alloc_node mm/slub.c:5233 [inline]
__do_kmalloc_node mm/slub.c:5602 [inline]
__kmalloc_node_track_caller_noprof+0x4a5/0x850 mm/slub.c:5712
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:601
__alloc_skb+0x166/0x380 net/core/skbuff.c:670
alloc_skb include/linux/skbuff.h:1383 [inline]
alloc_skb_with_frags+0xe0/0x860 net/core/skbuff.c:6671
sock_alloc_send_pskb+0x7f9/0x980 net/core/sock.c:2965
unix_dgram_sendmsg+0x3e9/0x17f0 net/unix/af_unix.c:2153
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
sock_write_iter+0x563/0x610 net/socket.c:1195
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x7d3/0x11d0 fs/read_write.c:686
ksys_write+0x1f8/0x250 fs/read_write.c:738
page last free pid 8405 tgid 8405 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
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+0x4e/0x70 mm/kasan/common.c:352
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4946 [inline]
slab_alloc_node mm/slub.c:5245 [inline]
__do_kmalloc_node mm/slub.c:5602 [inline]
__kvmalloc_node_noprof+0x32c/0x910 mm/slub.c:7036
seq_buf_alloc fs/seq_file.c:38 [inline]
seq_read_iter+0x830/0x12d0 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/0x4d0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88812e8abe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88812e8abf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88812e8abf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88812e8ac000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88812e8ac080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: 00 e8 add %ch,%al
2: 72 9f jb 0xffffffa3
4: 28 00 sub %al,(%rax)
6: 9c pushf
7: 5b pop %rbx
8: 81 e3 00 02 00 00 and $0x200,%ebx
e: 31 ff xor %edi,%edi
10: 48 89 de mov %rbx,%rsi
13: e8 d0 b5 20 00 call 0x20b5e8
18: 48 85 db test %rbx,%rbx
1b: 0f 85 55 01 00 00 jne 0x176
21: e8 52 ba 20 00 call 0x20ba78
26: fb sti
27: 4c 89 e0 mov %r12,%rax
* 2a: 48 c1 e8 03 shr $0x3,%rax <-- trapping instruction
2e: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1)
33: 0f 84 11 ff ff ff je 0xffffff4a
39: 4c 89 e7 mov %r12,%rdi
3c: e8 .byte 0xe8
3d: c7 (bad)
3e: da .byte 0xda
3f: 80 .byte 0x80