==================================================================
BUG: KASAN: use-after-free in snd_usbmidi_error_timer+0x5fe/0x660 sound/usb/midi.c:352
Read of size 1 at addr ffff8880617ad943 by task dhcpcd-run-hook/4707
CPU: 1 PID: 4707 Comm: dhcpcd-run-hook Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
print_address_description+0x60/0x2d0 mm/kasan/report.c:248
__kasan_report mm/kasan/report.c:434 [inline]
kasan_report+0xdf/0x130 mm/kasan/report.c:451
snd_usbmidi_error_timer+0x5fe/0x660 sound/usb/midi.c:352
call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
expire_timers kernel/time/timer.c:1496 [inline]
__run_timers+0x525/0x7c0 kernel/time/timer.c:1767
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
handle_softirqs+0x328/0x820 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:instrument_atomic_read include/linux/instrumented.h:71 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
RIP: 0010:lock_page_memcg+0x20c/0x410 mm/memcontrol.c:2062
Code: ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 f6 44 24 41 02 0f 85 f9 00 00 00 f7 c3 00 02 00 00 74 01 fb 4d 8d af 80 10 00 00 <4c> 89 ef be 04 00 00 00 e8 f7 95 fb ff 4c 89 e8 48 c1 e8 03 48 b9
RSP: 0000:ffffc9000327f9c0 EFLAGS: 00000206
RAX: 20171fb31010c800 RBX: 0000000000000286 RCX: 20171fb31010c800
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: ffffffff8a59e800
RBP: ffffc9000327fa90 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: ffff888016a7c670
R13: ffff888016a7d080 R14: ffffea0001438938 R15: ffff888016a7c000
page_add_file_rmap+0x185/0x940 mm/rmap.c:1219
do_set_pte+0x3c9/0x530 mm/memory.c:4069
filemap_map_pages+0xe7e/0x1390 mm/filemap.c:3344
do_fault_around mm/memory.c:4243 [inline]
do_read_fault mm/memory.c:4258 [inline]
do_fault mm/memory.c:4392 [inline]
handle_pte_fault mm/memory.c:4650 [inline]
__handle_mm_fault mm/memory.c:4785 [inline]
handle_mm_fault+0x257d/0x43b0 mm/memory.c:4883
do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357
handle_page_fault arch/x86/mm/fault.c:1445 [inline]
exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x7f555ac0c420
Code: Unable to access opcode bytes at RIP 0x7f555ac0c3f6.
RSP: 002b:00007ffe5c1f1a88 EFLAGS: 00010246
RAX: 0000561777599910 RBX: 000056177759b760 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 00005617775a14c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000561777599910
R13: 00005617775a14c0 R14: 0000000000000000 R15: 00007f555ae26460
Allocated by task 13:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
____kasan_kmalloc mm/kasan/common.c:513 [inline]
__kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522
kmalloc include/linux/slab.h:607 [inline]
kzalloc include/linux/slab.h:738 [inline]
snd_usbmidi_in_endpoint_create+0x7e/0xa20 sound/usb/midi.c:1342
snd_usbmidi_create_endpoints sound/usb/midi.c:1937 [inline]
__snd_usbmidi_create+0x16f8/0x2f90 sound/usb/midi.c:2659
snd_usb_create_quirk sound/usb/quirks.c:577 [inline]
create_composite_quirk+0x1ec/0x4e0 sound/usb/quirks.c:48
usb_audio_probe+0xb72/0x1d50 sound/usb/card.c:885
usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165
usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_new_device+0xd53/0x1640 drivers/usb/core/hub.c:2632
hub_port_connect drivers/usb/core/hub.c:5497 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
port_event drivers/usb/core/hub.c:5799 [inline]
hub_event+0x2dd9/0x5560 drivers/usb/core/hub.c:5881
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Freed by task 13:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:46
kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:1710 [inline]
slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736
slab_free mm/slub.c:3504 [inline]
kfree+0xef/0x2a0 mm/slub.c:4564
snd_usbmidi_free sound/usb/midi.c:1530 [inline]
snd_usbmidi_rawmidi_free+0xaa/0x150 sound/usb/midi.c:1590
snd_rawmidi_free+0x3b7/0x3e0 sound/core/rawmidi.c:1844
snd_rawmidi_dev_free+0x34/0x40 sound/core/rawmidi.c:1853
__snd_device_free+0x1cd/0x2e0 sound/core/device.c:76
snd_device_free_all+0xcb/0x180 sound/core/device.c:233
snd_card_do_free sound/core/init.c:588 [inline]
release_card_device+0x6d/0x1f0 sound/core/init.c:145
device_release+0x92/0x1c0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:713 [inline]
kobject_release lib/kobject.c:744 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x21d/0x460 lib/kobject.c:761
snd_card_free_when_closed sound/core/init.c:620 [inline]
snd_card_free+0x123/0x190 sound/core/init.c:653
usb_audio_probe+0x187f/0x1d50 sound/usb/card.c:939
usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165
usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x284/0xc80 drivers/base/dd.c:595
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:755
driver_probe_device+0x4f/0x420 drivers/base/dd.c:785
__device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907
bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
__device_attach+0x29b/0x460 drivers/base/dd.c:979
bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
device_add+0xa00/0xfb0 drivers/base/core.c:3412
usb_new_device+0xd53/0x1640 drivers/usb/core/hub.c:2632
hub_port_connect drivers/usb/core/hub.c:5497 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
port_event drivers/usb/core/hub.c:5799 [inline]
hub_event+0x2dd9/0x5560 drivers/usb/core/hub.c:5881
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
The buggy address belongs to the object at ffff8880617ad800
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 323 bytes inside of
512-byte region [ffff8880617ad800, ffff8880617ada00)
The buggy address belongs to the page:
page:ffffea000185eb00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x617ac
head:ffffea000185eb00 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888016841c80
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 4189, ts 55969749456, free_ts 11756648963
prep_new_page mm/page_alloc.c:2426 [inline]
get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192
__alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487
alloc_slab_page mm/slub.c:1780 [inline]
allocate_slab mm/slub.c:1917 [inline]
new_slab+0xc0/0x4b0 mm/slub.c:1980
___slab_alloc+0x81e/0xdf0 mm/slub.c:3013
__slab_alloc mm/slub.c:3100 [inline]
slab_alloc_node mm/slub.c:3191 [inline]
slab_alloc mm/slub.c:3233 [inline]
__kmalloc+0x1cd/0x330 mm/slub.c:4408
kmalloc include/linux/slab.h:612 [inline]
kzalloc include/linux/slab.h:738 [inline]
fib6_info_alloc+0x2e/0xe0 net/ipv6/ip6_fib.c:155
ip6_route_info_create+0x44f/0x1210 net/ipv6/route.c:3769
addrconf_f6i_alloc+0x1b9/0x3f0 net/ipv6/route.c:4592
fixup_permanent_addr net/ipv6/addrconf.c:3509 [inline]
addrconf_permanent_addr+0x26e/0x980 net/ipv6/addrconf.c:3548
addrconf_notify+0x827/0xf00 net/ipv6/addrconf.c:3616
notifier_call_chain kernel/notifier.c:83 [inline]
raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391
call_netdevice_notifiers_extack net/core/dev.c:2061 [inline]
call_netdevice_notifiers net/core/dev.c:2075 [inline]
__dev_notify_flags+0x178/0x2d0 net/core/dev.c:-1
dev_change_flags+0xe3/0x1a0 net/core/dev.c:8929
do_setlink+0xc01/0x3980 net/core/rtnetlink.c:2781
__rtnl_newlink net/core/rtnetlink.c:3452 [inline]
rtnl_newlink+0x1419/0x17d0 net/core/rtnetlink.c:3574
rtnetlink_rcv_msg+0x7ff/0xe90 net/core/rtnetlink.c:5684
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1340 [inline]
free_pcp_prepare mm/page_alloc.c:1391 [inline]
free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
free_unref_page+0x94/0x280 mm/page_alloc.c:3396
free_contig_range+0x96/0xf0 mm/page_alloc.c:9406
destroy_args+0x100/0xa20 mm/debug_vm_pgtable.c:1018
debug_vm_pgtable+0x318/0x370 mm/debug_vm_pgtable.c:1336
do_one_initcall+0x1ee/0x680 init/main.c:1316
do_initcall_level+0x137/0x1f0 init/main.c:1389
do_initcalls+0x4b/0x90 init/main.c:1405
kernel_init_freeable+0x3ce/0x560 init/main.c:1629
kernel_init+0x19/0x1b0 init/main.c:1520
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Memory state around the buggy address:
ffff8880617ad800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880617ad880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880617ad900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880617ad980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880617ada00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
0: ff 48 c7 decl -0x39(%rax)
3: 44 24 40 rex.R and $0x40,%al
6: 00 00 add %al,(%rax)
8: 00 00 add %al,(%rax)
a: 9c pushf
b: 8f 44 24 40 pop 0x40(%rsp)
f: f6 44 24 41 02 testb $0x2,0x41(%rsp)
14: 0f 85 f9 00 00 00 jne 0x113
1a: f7 c3 00 02 00 00 test $0x200,%ebx
20: 74 01 je 0x23
22: fb sti
23: 4d 8d af 80 10 00 00 lea 0x1080(%r15),%r13
* 2a: 4c 89 ef mov %r13,%rdi <-- trapping instruction
2d: be 04 00 00 00 mov $0x4,%esi
32: e8 f7 95 fb ff call 0xfffb962e
37: 4c 89 e8 mov %r13,%rax
3a: 48 c1 e8 03 shr $0x3,%rax
3e: 48 rex.W
3f: b9 .byte 0xb9