usb 1-1: New USB device found, idVendor=0424, idProduct=cf30, bcdDevice=d3.ae
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 ffff88807de398a0 by task kworker/1:2/798

CPU: 1 UID: 0 PID: 798 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 hdm_disconnect+0x10d/0x1c0 drivers/most/most_usb.c:1125
 usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:571 [inline]
 __device_release_driver drivers/base/dd.c:1274 [inline]
 device_release_driver_internal+0x4d9/0x800 drivers/base/dd.c:1297
 bus_remove_device+0x34d/0x410 drivers/base/bus.c:579
 device_del+0x511/0x8e0 drivers/base/core.c:3878
 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1418
 usb_disconnect+0x330/0x950 drivers/usb/core/hub.c:2339
 hub_port_connect drivers/usb/core/hub.c:5401 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5701 [inline]
 port_event drivers/usb/core/hub.c:5865 [inline]
 hub_event+0x1cf5/0x4a20 drivers/usb/core/hub.c:5947
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 798:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5748
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 hdm_probe+0x96/0x1400 drivers/most/most_usb.c:959
 usb_probe_interface+0x668/0xc30 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x26d/0x9e0 drivers/base/dd.c:659
 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959
 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3689
 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
 usb_probe_device+0x1c4/0x390 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x26d/0x9e0 drivers/base/dd.c:659
 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959
 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3689
 usb_new_device+0xa39/0x16f0 drivers/usb/core/hub.c:2689
 hub_port_connect drivers/usb/core/hub.c:5561 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5701 [inline]
 port_event drivers/usb/core/hub.c:5865 [inline]
 hub_event+0x2958/0x4a20 drivers/usb/core/hub.c:5947
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 798:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 __kasan_save_free_info+0x46/0x50 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+0x5c/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2523 [inline]
 slab_free mm/slub.c:6612 [inline]
 kfree+0x19a/0x6d0 mm/slub.c:6819
 device_release+0x9c/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+0x22b/0x480 lib/kobject.c:737
 hdm_disconnect+0xf3/0x1c0 drivers/most/most_usb.c:1123
 usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:571 [inline]
 __device_release_driver drivers/base/dd.c:1274 [inline]
 device_release_driver_internal+0x4d9/0x800 drivers/base/dd.c:1297
 bus_remove_device+0x34d/0x410 drivers/base/bus.c:579
 device_del+0x511/0x8e0 drivers/base/core.c:3878
 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1418
 usb_disconnect+0x330/0x950 drivers/usb/core/hub.c:2339
 hub_port_connect drivers/usb/core/hub.c:5401 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5701 [inline]
 port_event drivers/usb/core/hub.c:5865 [inline]
 hub_event+0x1cf5/0x4a20 drivers/usb/core/hub.c:5947
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88807de38000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 6304 bytes inside of
 freed 8192-byte region [ffff88807de38000, ffff88807de3a000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7de38
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813fe27280 ffffea000084ec00 dead000000000005
raw: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813fe27280 ffffea000084ec00 dead000000000005
head: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001f78e01 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 5194, tgid 5194 (rcS), ts 25171419736, free_ts 22833143199
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3884
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2418
 alloc_slab_page mm/slub.c:3039 [inline]
 allocate_slab+0x96/0x3a0 mm/slub.c:3212
 new_slab mm/slub.c:3266 [inline]
 ___slab_alloc+0xe94/0x18a0 mm/slub.c:4636
 __slab_alloc+0x65/0x100 mm/slub.c:4755
 __slab_alloc_node mm/slub.c:4831 [inline]
 slab_alloc_node mm/slub.c:5253 [inline]
 __kmalloc_cache_noprof+0x41e/0x700 mm/slub.c:5743
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 tomoyo_print_bprm security/tomoyo/audit.c:26 [inline]
 tomoyo_init_log+0x111f/0x1f70 security/tomoyo/audit.c:264
 tomoyo_supervisor+0x340/0x1480 security/tomoyo/common.c:2198
 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline]
 tomoyo_env_perm+0x149/0x1e0 security/tomoyo/environ.c:63
 tomoyo_environ security/tomoyo/domain.c:672 [inline]
 tomoyo_find_next_domain+0x15cf/0x1aa0 security/tomoyo/domain.c:888
 tomoyo_bprm_check_security+0x11c/0x180 security/tomoyo/tomoyo.c:102
 security_bprm_check+0x89/0x270 security/security.c:1341
 search_binary_handler fs/exec.c:1660 [inline]
 exec_binprm fs/exec.c:1702 [inline]
 bprm_execve+0x8ee/0x1450 fs/exec.c:1754
 do_execveat_common+0x510/0x6a0 fs/exec.c:1860
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906
 __free_pages mm/page_alloc.c:5302 [inline]
 free_contig_range+0x1bd/0x4a0 mm/page_alloc.c:7146
 destroy_args+0x69/0x660 mm/debug_vm_pgtable.c:958
 debug_vm_pgtable+0x39f/0x3b0 mm/debug_vm_pgtable.c:1345
 do_one_initcall+0x236/0x820 init/main.c:1283
 do_initcall_level+0x104/0x190 init/main.c:1345
 do_initcalls+0x59/0xa0 init/main.c:1361
 kernel_init_freeable+0x334/0x4b0 init/main.c:1593
 kernel_init+0x1d/0x1d0 init/main.c:1483
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88807de39780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807de39800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807de39880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff88807de39900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807de39980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================