em28xx 1-1:246.0: unknown em28xx chip ID (0) em28xx 1-1:246.0: Config register raw data: 0x1b em28xx 1-1:246.0: AC97 chip type couldn't be determined em28xx 1-1:246.0: No AC97 audio processor ================================================================== BUG: KASAN: slab-use-after-free in __list_add_valid_or_report+0x6a/0x130 lib/list_debug.c:32 Read of size 8 at addr ffff88807bdec250 by task kworker/1:4/5905 CPU: 1 UID: 0 PID: 5905 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 __list_add_valid_or_report+0x6a/0x130 lib/list_debug.c:32 __list_add_valid include/linux/list.h:96 [inline] __list_add include/linux/list.h:158 [inline] list_add_tail include/linux/list.h:191 [inline] em28xx_init_extension+0x56/0x1c0 drivers/media/usb/em28xx/em28xx-core.c:1114 em28xx_init_dev+0xc01/0x3280 drivers/media/usb/em28xx/em28xx-cards.c:3686 em28xx_usb_probe+0x157b/0x2b10 drivers/media/usb/em28xx/em28xx-cards.c:4041 usb_probe_interface+0x668/0xc90 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:721 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:863 driver_probe_device+0x4f/0x240 drivers/base/dd.c:893 __device_attach_driver+0x279/0x430 drivers/base/dd.c:1021 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c5/0x450 drivers/base/dd.c:1093 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x12a/0x220 drivers/base/bus.c:613 device_add+0x7b6/0xb70 drivers/base/core.c:3692 usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2266 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x3b0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:721 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:863 driver_probe_device+0x4f/0x240 drivers/base/dd.c:893 __device_attach_driver+0x279/0x430 drivers/base/dd.c:1021 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c5/0x450 drivers/base/dd.c:1093 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1148 bus_probe_device+0x12a/0x220 drivers/base/bus.c:613 device_add+0x7b6/0xb70 drivers/base/core.c:3692 usb_new_device+0xa08/0x16f0 drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x2a1c/0x4f30 drivers/usb/core/hub.c:5953 process_one_work+0x9ab/0x1780 kernel/workqueue.c:3288 process_scheduled_works kernel/workqueue.c:3379 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3465 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 0: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4950 kmalloc_reserve net/core/skbuff.c:613 [inline] __alloc_skb+0x27d/0x7d0 net/core/skbuff.c:713 __netdev_alloc_skb+0xc1/0x810 net/core/skbuff.c:775 netdev_alloc_skb include/linux/skbuff.h:3494 [inline] dev_alloc_skb include/linux/skbuff.h:3507 [inline] __ieee80211_beacon_get+0xc06/0x1880 net/mac80211/tx.c:5687 ieee80211_beacon_get_tim+0xbd/0x2c0 net/mac80211/tx.c:5809 ieee80211_beacon_get include/net/mac80211.h:5724 [inline] mac80211_hwsim_beacon_tx+0x3c5/0x870 drivers/net/wireless/virtual/mac80211_hwsim.c:2497 __iterate_interfaces+0x2ab/0x590 net/mac80211/util.c:760 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:796 mac80211_hwsim_beacon+0xbb/0x180 drivers/net/wireless/virtual/mac80211_hwsim.c:2531 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x3d1/0xa70 kernel/time/hrtimer.c:1994 hrtimer_run_softirq+0x17a/0x240 kernel/time/hrtimer.c:2011 handle_softirqs+0x22a/0x870 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:739 irq_exit_rcu+0x9/0x30 kernel/softirq.c:756 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 Freed by task 0: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6242 [inline] kmem_cache_free+0x189/0x640 mm/slub.c:6369 skb_kfree_head net/core/skbuff.c:1076 [inline] skb_free_head net/core/skbuff.c:1090 [inline] skb_release_data+0x81c/0xa80 net/core/skbuff.c:1117 skb_release_all net/core/skbuff.c:1192 [inline] __kfree_skb+0x5d/0x210 net/core/skbuff.c:1206 mac80211_hwsim_beacon_tx+0x3e8/0x870 drivers/net/wireless/virtual/mac80211_hwsim.c:2501 __iterate_interfaces+0x2ab/0x590 net/mac80211/util.c:760 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:796 mac80211_hwsim_beacon+0xbb/0x180 drivers/net/wireless/virtual/mac80211_hwsim.c:2531 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x3d1/0xa70 kernel/time/hrtimer.c:1994 hrtimer_run_softirq+0x17a/0x240 kernel/time/hrtimer.c:2011 handle_softirqs+0x22a/0x870 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:739 irq_exit_rcu+0x9/0x30 kernel/softirq.c:756 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 The buggy address belongs to the object at ffff88807bdec000 which belongs to the cache skbuff_small_head of size 704 The buggy address is located 592 bytes inside of freed 704-byte region [ffff88807bdec000, ffff88807bdec2c0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7bdec head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801f2cea00 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800130013 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801f2cea00 dead000000000100 dead000000000122 head: 0000000000000000 0000000800130013 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 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 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 0, tgid 0 (swapper/1), ts 80210453527, free_ts 80156715036 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1857 prep_new_page mm/page_alloc.c:1865 [inline] get_page_from_freelist+0x2418/0x24b0 mm/page_alloc.c:3924 __alloc_frozen_pages_noprof+0x233/0x3d0 mm/page_alloc.c:5211 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab+0x77/0x660 mm/slub.c:3467 new_slab mm/slub.c:3525 [inline] refill_objects+0x339/0x3d0 mm/slub.c:7247 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x321/0x720 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] kmem_cache_alloc_node_noprof+0x441/0x690 mm/slub.c:4950 kmalloc_reserve net/core/skbuff.c:613 [inline] __alloc_skb+0x27d/0x7d0 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] ndisc_alloc_skb+0x9f/0x480 net/ipv6/ndisc.c:420 ndisc_send_rs+0x2b5/0x630 net/ipv6/ndisc.c:706 addrconf_rs_timer+0x395/0x6d0 net/ipv6/addrconf.c:4041 call_timer_fn+0x192/0x640 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2373 [inline] __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385 run_timer_base kernel/time/timer.c:2394 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404 handle_softirqs+0x22a/0x870 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:739 page last free pid 5927 tgid 5927 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1401 [inline] __free_frozen_pages+0xbf0/0xd00 mm/page_alloc.c:2942 kref_put include/linux/kref.h:65 [inline] em28xx_usb_disconnect+0x27f/0x2f0 drivers/media/usb/em28xx/em28xx-cards.c:4211 usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:633 [inline] __device_release_driver drivers/base/dd.c:1344 [inline] device_release_driver_internal+0x4d9/0x870 drivers/base/dd.c:1367 bus_remove_device+0x455/0x570 drivers/base/bus.c:657 device_del+0x527/0x8f0 drivers/base/core.c:3881 usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1476 usb_disconnect+0x32f/0x990 drivers/usb/core/hub.c:2345 hub_port_connect drivers/usb/core/hub.c:5407 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x1cc9/0x4f30 drivers/usb/core/hub.c:5953 process_one_work+0x9ab/0x1780 kernel/workqueue.c:3288 process_scheduled_works kernel/workqueue.c:3379 [inline] worker_thread+0xbee/0x11e0 kernel/workqueue.c:3465 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 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: ffff88807bdec100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807bdec180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807bdec200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807bdec280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88807bdec300: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================