usb 1-1: USB disconnect, device number 2 ================================================================== BUG: KASAN: use-after-free in hdm_disconnect+0x109/0x1c0 drivers/most/most_usb.c:1125 Read of size 8 at addr ffff8880798cd898 by task kworker/0:2/127 CPU: 0 PID: 127 Comm: kworker/0:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 hdm_disconnect+0x109/0x1c0 drivers/most/most_usb.c:1125 usb_unbind_interface+0x1ee/0x860 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:550 [inline] __device_release_driver drivers/base/dd.c:1260 [inline] device_release_driver_internal+0x522/0x850 drivers/base/dd.c:1286 bus_remove_device+0x2e2/0x400 drivers/base/bus.c:531 device_del+0x628/0xa70 drivers/base/core.c:3885 usb_disable_device+0x3e2/0x890 drivers/usb/core/message.c:1414 usb_disconnect+0x348/0x8a0 drivers/usb/core/hub.c:2314 hub_port_connect drivers/usb/core/hub.c:5361 [inline] hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] port_event drivers/usb/core/hub.c:5817 [inline] hub_event+0x1e24/0x54e0 drivers/usb/core/hub.c:5899 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 process_scheduled_works kernel/workqueue.c:2355 [inline] worker_thread+0xd62/0x1250 kernel/workqueue.c:2441 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 127: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] hdm_probe+0x8f/0x13d0 drivers/most/most_usb.c:959 usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2aa/0xc70 drivers/base/dd.c:639 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:1015 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3697 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+0x2aa/0xc70 drivers/base/dd.c:639 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:1015 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3697 usb_new_device+0xd4d/0x1620 drivers/usb/core/hub.c:2659 hub_port_connect drivers/usb/core/hub.c:5517 [inline] hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] port_event drivers/usb/core/hub.c:5817 [inline] hub_event+0x2d5e/0x54e0 drivers/usb/core/hub.c:5899 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Freed by task 127: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700 device_release+0x92/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:681 [inline] kobject_release lib/kobject.c:712 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x21d/0x460 lib/kobject.c:729 hdm_disconnect+0xef/0x1c0 drivers/most/most_usb.c:1123 usb_unbind_interface+0x1ee/0x860 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:550 [inline] __device_release_driver drivers/base/dd.c:1260 [inline] device_release_driver_internal+0x522/0x850 drivers/base/dd.c:1286 bus_remove_device+0x2e2/0x400 drivers/base/bus.c:531 device_del+0x628/0xa70 drivers/base/core.c:3885 usb_disable_device+0x3e2/0x890 drivers/usb/core/message.c:1414 usb_disconnect+0x348/0x8a0 drivers/usb/core/hub.c:2314 hub_port_connect drivers/usb/core/hub.c:5361 [inline] hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] port_event drivers/usb/core/hub.c:5817 [inline] hub_event+0x1e24/0x54e0 drivers/usb/core/hub.c:5899 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 process_scheduled_works kernel/workqueue.c:2355 [inline] worker_thread+0xd62/0x1250 kernel/workqueue.c:2441 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 insert_work+0x54/0x3c0 kernel/workqueue.c:1361 __queue_work+0xba3/0xfb0 kernel/workqueue.c:1520 queue_work_on+0x11d/0x1d0 kernel/workqueue.c:1548 kref_put include/linux/kref.h:65 [inline] sg_release+0x1d0/0x2c0 drivers/scsi/sg.c:404 __fput+0x22c/0x920 fs/file_table.c:320 task_work_run+0x1ca/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff8880798cc000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 6296 bytes inside of 8192-byte region [ffff8880798cc000, ffff8880798ce000) The buggy address belongs to the physical page: page:ffffea0001e63200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x798c8 head:ffffea0001e63200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888017442280 raw: 0000000000000000 0000000080020002 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3947, tgid 3947 (dhcpcd-run-hook), ts 47310582399, free_ts 47280316389 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1230 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] tomoyo_print_bprm security/tomoyo/audit.c:26 [inline] tomoyo_init_log+0x1081/0x1f50 security/tomoyo/audit.c:264 tomoyo_supervisor+0x326/0x10b0 security/tomoyo/common.c:2088 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline] tomoyo_env_perm+0x146/0x1e0 security/tomoyo/environ.c:63 tomoyo_environ security/tomoyo/domain.c:672 [inline] tomoyo_find_next_domain+0x157a/0x1a40 security/tomoyo/domain.c:882 tomoyo_bprm_check_security+0x100/0x150 security/tomoyo/tomoyo.c:101 security_bprm_check+0x5e/0x90 security/security.c:869 search_binary_handler fs/exec.c:1752 [inline] exec_binprm fs/exec.c:1805 [inline] bprm_execve+0xa77/0x18a0 fs/exec.c:1874 do_execveat_common+0x51b/0x6c0 fs/exec.c:1979 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383 mt_alloc_one lib/maple_tree.c:152 [inline] mas_alloc_nodes+0x2ec/0x890 lib/maple_tree.c:1277 mas_node_count_gfp lib/maple_tree.c:1359 [inline] mas_preallocate+0x161/0x3c0 lib/maple_tree.c:5807 vma_expand+0x27a/0x880 mm/mmap.c:544 __mmap_region mm/mmap.c:2740 [inline] mmap_region+0xc24/0x1c70 mm/mmap.c:2916 do_mmap+0x958/0xfd0 mm/mmap.c:1436 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:520 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482 Memory state around the buggy address: ffff8880798cd780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880798cd800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880798cd880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880798cd900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880798cd980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================