dvb-usb: error while querying for an remote control event. ================================================================== 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 ffff8880767a0250 by task kworker/1:6/5896 CPU: 1 UID: 0 PID: 5896 Comm: kworker/1:6 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: events request_module_async Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 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 process_one_work+0x949/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9af/0xee0 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5199: 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:4406 [inline] slab_alloc_node mm/slub.c:4735 [inline] kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4787 kmalloc_reserve net/core/skbuff.c:612 [inline] __alloc_skb+0x27d/0x7d0 net/core/skbuff.c:712 alloc_skb include/linux/skbuff.h:1383 [inline] alloc_uevent_skb+0x7d/0x230 lib/kobject_uevent.c:289 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline] kobject_uevent_net_broadcast+0x2fa/0x560 lib/kobject_uevent.c:410 kobject_uevent_env+0x55c/0x9e0 lib/kobject_uevent.c:608 kobject_synth_uevent+0x585/0xbd0 lib/kobject_uevent.c:207 uevent_store+0x26/0x70 drivers/base/core.c:2773 kernfs_fop_write_iter+0x3af/0x540 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5199: 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:2621 [inline] slab_free mm/slub.c:6026 [inline] kmem_cache_free+0x180/0x610 mm/slub.c:6152 skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1127 skb_release_all net/core/skbuff.c:1202 [inline] __kfree_skb net/core/skbuff.c:1216 [inline] consume_skb+0x9e/0xf0 net/core/skbuff.c:1449 netlink_recvmsg+0x5d6/0xa50 net/netlink/af_netlink.c:1972 sock_recvmsg_nosec+0x186/0x1c0 net/socket.c:1093 ____sys_recvmsg+0x245/0x510 net/socket.c:-1 ___sys_recvmsg+0x215/0x590 net/socket.c:2872 __sys_recvmsg net/socket.c:2905 [inline] __do_sys_recvmsg net/socket.c:2911 [inline] __se_sys_recvmsg net/socket.c:2908 [inline] __x64_sys_recvmsg+0x1ba/0x2a0 net/socket.c:2908 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880767a0000 which belongs to the cache skbuff_small_head of size 704 The buggy address is located 592 bytes inside of freed 704-byte region [ffff8880767a0000, ffff8880767a02c0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x767a0 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 ffff8881404c3b40 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff8881404c3b40 dead000000000100 dead000000000122 head: 0000000000000000 0000000000130013 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0001d9e801 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5199, tgid 5199 (udevd), ts 238951207561, free_ts 238588200197 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1883 prep_new_page mm/page_alloc.c:1891 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3956 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5244 alloc_slab_page mm/slub.c:3189 [inline] allocate_slab+0x7b/0x660 mm/slub.c:3362 new_slab mm/slub.c:3420 [inline] refill_objects+0x33a/0x3d0 mm/slub.c:7028 refill_sheaf mm/slub.c:2738 [inline] __pcs_replace_empty_main+0x2b9/0x620 mm/slub.c:4483 alloc_from_pcs mm/slub.c:4586 [inline] slab_alloc_node mm/slub.c:4720 [inline] kmem_cache_alloc_node_noprof+0x441/0x690 mm/slub.c:4787 kmalloc_reserve net/core/skbuff.c:612 [inline] __alloc_skb+0x27d/0x7d0 net/core/skbuff.c:712 netlink_sendmsg+0x5d4/0xb40 net/netlink/af_netlink.c:1869 sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737 __sock_sendmsg net/socket.c:752 [inline] ____sys_sendmsg+0x589/0x8c0 net/socket.c:2610 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2664 __sys_sendmsg net/socket.c:2696 [inline] __do_sys_sendmsg net/socket.c:2701 [inline] __se_sys_sendmsg net/socket.c:2699 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2699 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5841 tgid 5841 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1432 [inline] __free_frozen_pages+0xbb9/0xd10 mm/page_alloc.c:2972 kref_put include/linux/kref.h:65 [inline] em28xx_usb_disconnect+0x27f/0x2f0 drivers/media/usb/em28xx/em28xx-cards.c:4204 usb_unbind_interface+0x26e/0x910 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:573 [inline] __device_release_driver drivers/base/dd.c:1284 [inline] device_release_driver_internal+0x4d9/0x860 drivers/base/dd.c:1307 bus_remove_device+0x34d/0x440 drivers/base/bus.c:616 device_del+0x527/0x8f0 drivers/base/core.c:3878 usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1418 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+0x949/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9f4/0xee0 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 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: ffff8880767a0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880767a0180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880767a0200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880767a0280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880767a0300: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================