usb 1-1: New USB device found, idVendor=0424, idProduct=cf18, bcdDevice=25.5e
usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1: Product: syz
usb 1-1: Manufacturer: syz
usb 1-1: SerialNumber: syz
usb 1-1: USB disconnect, device number 2
==================================================================
BUG: KASAN: slab-use-after-free in hdm_disconnect+0x10d/0x1c0 drivers/most/most_usb.c:1125
Read of size 8 at addr ffff888026a19898 by task kworker/0:1/9
CPU: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.6.95-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0xac/0x230 mm/kasan/report.c:475
kasan_report+0x117/0x150 mm/kasan/report.c:588
hdm_disconnect+0x10d/0x1c0 drivers/most/most_usb.c:1125
usb_unbind_interface+0x1f2/0x870 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:569 [inline]
__device_release_driver drivers/base/dd.c:1272 [inline]
device_release_driver_internal+0x4cb/0x7a0 drivers/base/dd.c:1295
bus_remove_device+0x342/0x400 drivers/base/bus.c:576
device_del+0x50b/0x900 drivers/base/core.c:3872
usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1416
usb_disconnect+0x34c/0x8a0 drivers/usb/core/hub.c:2287
hub_port_connect drivers/usb/core/hub.c:5341 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5641 [inline]
port_event drivers/usb/core/hub.c:5801 [inline]
hub_event+0x1ce5/0x49c0 drivers/usb/core/hub.c:5883
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
Allocated by task 9:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
____kasan_kmalloc mm/kasan/common.c:374 [inline]
__kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383
kmalloc include/linux/slab.h:600 [inline]
kzalloc include/linux/slab.h:721 [inline]
hdm_probe+0x96/0x13e0 drivers/most/most_usb.c:959
usb_probe_interface+0x5a4/0xb00 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x25b/0xb40 drivers/base/dd.c:658
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
__device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
__device_attach+0x2b5/0x400 drivers/base/dd.c:1030
bus_probe_device+0x180/0x260 drivers/base/bus.c:534
device_add+0x85b/0xc20 drivers/base/core.c:3683
usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2207
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238
usb_probe_device+0x13d/0x280 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x25b/0xb40 drivers/base/dd.c:658
__driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
__device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
__device_attach+0x2b5/0x400 drivers/base/dd.c:1030
bus_probe_device+0x180/0x260 drivers/base/bus.c:534
device_add+0x85b/0xc20 drivers/base/core.c:3683
usb_new_device+0xa31/0x1630 drivers/usb/core/hub.c:2632
hub_port_connect drivers/usb/core/hub.c:5501 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5641 [inline]
port_event drivers/usb/core/hub.c:5801 [inline]
hub_event+0x2957/0x49c0 drivers/usb/core/hub.c:5883
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Freed by task 9:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1806 [inline]
slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832
slab_free mm/slub.c:3816 [inline]
__kmem_cache_free+0xba/0x1f0 mm/slub.c:3829
device_release+0x96/0x1c0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x221/0x470 lib/kobject.c:737
hdm_disconnect+0xf3/0x1c0 drivers/most/most_usb.c:1123
usb_unbind_interface+0x1f2/0x870 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:569 [inline]
__device_release_driver drivers/base/dd.c:1272 [inline]
device_release_driver_internal+0x4cb/0x7a0 drivers/base/dd.c:1295
bus_remove_device+0x342/0x400 drivers/base/bus.c:576
device_del+0x50b/0x900 drivers/base/core.c:3872
usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1416
usb_disconnect+0x34c/0x8a0 drivers/usb/core/hub.c:2287
hub_port_connect drivers/usb/core/hub.c:5341 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5641 [inline]
port_event drivers/usb/core/hub.c:5801 [inline]
hub_event+0x1ce5/0x49c0 drivers/usb/core/hub.c:5883
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
The buggy address belongs to the object at ffff888026a18000
which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 6296 bytes inside of
freed 8192-byte region [ffff888026a18000, ffff888026a1a000)
The buggy address belongs to the physical page:
page:ffffea00009a8600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888026a1c000 pfn:0x26a18
head:ffffea00009a8600 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 ffff888017842280 ffffea0001f95400 0000000000000006
raw: ffff888026a1c000 0000000080020001 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 0xd28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5707, tgid 5707 (sshd-session), ts 52875090794, free_ts 52777288441
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
prep_new_page mm/page_alloc.c:1561 [inline]
get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
__alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
alloc_slab_page+0x5d/0x170 mm/slub.c:1876
allocate_slab mm/slub.c:2023 [inline]
new_slab+0x87/0x2e0 mm/slub.c:2076
___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230
__slab_alloc mm/slub.c:3329 [inline]
__slab_alloc_node mm/slub.c:3382 [inline]
slab_alloc_node mm/slub.c:3475 [inline]
__kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc_node_track_caller+0xa2/0x230 mm/slab_common.c:1027
kmalloc_reserve+0x117/0x260 net/core/skbuff.c:581
__alloc_skb+0x138/0x2c0 net/core/skbuff.c:650
alloc_skb include/linux/skbuff.h:1284 [inline]
netlink_dump+0x1e2/0xe10 net/netlink/af_netlink.c:2216
netlink_recvmsg+0x677/0xdf0 net/netlink/af_netlink.c:1973
sock_recvmsg_nosec net/socket.c:1046 [inline]
sock_recvmsg net/socket.c:1068 [inline]
____sys_recvmsg+0x29e/0x5b0 net/socket.c:2814
___sys_recvmsg+0x1b6/0x510 net/socket.c:2856
__sys_recvmsg net/socket.c:2886 [inline]
__do_sys_recvmsg net/socket.c:2896 [inline]
__se_sys_recvmsg net/socket.c:2893 [inline]
__x64_sys_recvmsg+0x1f2/0x2c0 net/socket.c:2893
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1154 [inline]
free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
discard_slab mm/slub.c:2122 [inline]
__unfreeze_partials+0x1cf/0x210 mm/slub.c:2662
put_cpu_partial+0x17c/0x250 mm/slub.c:2738
__slab_free+0x31d/0x410 mm/slub.c:3686
qlink_free mm/kasan/quarantine.c:166 [inline]
qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185
kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
slab_alloc_node mm/slub.c:3485 [inline]
__kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3524
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc+0xa4/0x240 mm/slab_common.c:1020
kmalloc include/linux/slab.h:604 [inline]
tomoyo_add_entry security/tomoyo/common.c:2023 [inline]
tomoyo_supervisor+0xb70/0x1080 security/tomoyo/common.c:2095
tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline]
tomoyo_env_perm+0x14a/0x1e0 security/tomoyo/environ.c:63
tomoyo_environ security/tomoyo/domain.c:672 [inline]
tomoyo_find_next_domain+0x1594/0x1a60 security/tomoyo/domain.c:881
tomoyo_bprm_check_security+0x116/0x170 security/tomoyo/tomoyo.c:101
security_bprm_check+0x62/0xa0 security/security.c:1103
Memory state around the buggy address:
ffff888026a19780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888026a19800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888026a19880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888026a19900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888026a19980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================