em28xx 1-1:0.132: Closing video extension em28xx 1-1:0.132: Closing input extension ================================================================== BUG: KASAN: slab-use-after-free in media_device_unregister+0x13f/0x440 drivers/media/mc/mc-device.c:833 Read of size 8 at addr ffff888057dd4208 by task kworker/1:2/915 CPU: 1 UID: 0 PID: 915 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 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 media_device_unregister+0x13f/0x440 drivers/media/mc/mc-device.c:833 em28xx_unregister_media_device drivers/media/usb/em28xx/em28xx-cards.c:3777 [inline] em28xx_release_resources+0xac/0x240 drivers/media/usb/em28xx/em28xx-cards.c:3798 em28xx_usb_disconnect+0x19f/0x2f0 drivers/media/usb/em28xx/em28xx-cards.c:4492 usb_unbind_interface+0x295/0x9c0 drivers/usb/core/driver.c:460 device_remove drivers/base/dd.c:619 [inline] __device_release_driver drivers/base/dd.c:1357 [inline] device_release_driver_internal+0x48d/0x7d0 drivers/base/dd.c:1380 bus_remove_device+0x444/0x560 drivers/base/bus.c:678 device_del+0x524/0x8f0 drivers/base/core.c:3967 usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1484 usb_disconnect+0x346/0x9a0 drivers/usb/core/hub.c:2355 hub_port_connect drivers/usb/core/hub.c:5425 [inline] hub_port_connect_change drivers/usb/core/hub.c:5725 [inline] port_event drivers/usb/core/hub.c:5889 [inline] hub_event+0x1bbb/0x4d30 drivers/usb/core/hub.c:5971 process_one_work kernel/workqueue.c:3495 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 6117: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:409 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x600 mm/slub.c:5680 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] em28xx_v4l2_init+0xff/0x31f0 drivers/media/usb/em28xx/em28xx-video.c:2751 em28xx_init_extension+0x120/0x1d0 drivers/media/usb/em28xx/em28xx-core.c:1245 process_one_work kernel/workqueue.c:3495 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 915: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:264 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2780 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x1c5/0x650 mm/slub.c:6923 em28xx_free_v4l2+0x77/0xf0 drivers/media/usb/em28xx/em28xx-video.c:2337 v4l2_device_release drivers/media/v4l2-core/v4l2-device.c:51 [inline] kref_put include/linux/kref.h:65 [inline] v4l2_device_put+0x81/0xd0 drivers/media/v4l2-core/v4l2-device.c:56 em28xx_v4l2_fini+0x1f3/0x3e0 drivers/media/usb/em28xx/em28xx-video.c:2465 em28xx_close_extension+0xde/0x390 drivers/media/usb/em28xx/em28xx-core.c:1262 em28xx_usb_disconnect+0x16b/0x2f0 drivers/media/usb/em28xx/em28xx-cards.c:4488 usb_unbind_interface+0x295/0x9c0 drivers/usb/core/driver.c:460 device_remove drivers/base/dd.c:619 [inline] __device_release_driver drivers/base/dd.c:1357 [inline] device_release_driver_internal+0x48d/0x7d0 drivers/base/dd.c:1380 bus_remove_device+0x444/0x560 drivers/base/bus.c:678 device_del+0x524/0x8f0 drivers/base/core.c:3967 usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1484 usb_disconnect+0x346/0x9a0 drivers/usb/core/hub.c:2355 hub_port_connect drivers/usb/core/hub.c:5425 [inline] hub_port_connect_change drivers/usb/core/hub.c:5725 [inline] port_event drivers/usb/core/hub.c:5889 [inline] hub_event+0x1bbb/0x4d30 drivers/usb/core/hub.c:5971 process_one_work kernel/workqueue.c:3495 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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 ffff888057dd4000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 520 bytes inside of freed 8192-byte region [ffff888057dd4000, ffff888057dd6000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x57dd0 head: order:3 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 ffff88813ff26280 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ff26280 dead000000000100 dead000000000122 head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1240, tgid 1240 (kworker/0:2), ts 312773357142 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x2224/0x2290 mm/page_alloc.c:3940 __alloc_frozen_pages_noprof+0x1fe/0x410 mm/page_alloc.c:5464 alloc_slab_page mm/slub.c:3384 [inline] allocate_slab+0x7d/0x5e0 mm/slub.c:3499 new_slab mm/slub.c:3550 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7539 refill_sheaf mm/slub.c:2917 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4811 alloc_from_pcs mm/slub.c:4887 [inline] slab_alloc_node mm/slub.c:5021 [inline] __kmalloc_cache_noprof+0x396/0x600 mm/slub.c:5676 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] em28xx_v4l2_init+0xff/0x31f0 drivers/media/usb/em28xx/em28xx-video.c:2751 em28xx_init_extension+0x120/0x1d0 drivers/media/usb/em28xx/em28xx-core.c:1245 process_one_work kernel/workqueue.c:3495 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 6294 tgid 6294 ts 312750376140 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1403 [inline] __free_frozen_pages+0xc97/0xd90 mm/page_alloc.c:2957 __slab_free+0x269/0x2c0 mm/slub.c:5926 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:361 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4720 [inline] slab_alloc_node mm/slub.c:5033 [inline] __kmalloc_cache_noprof+0x29a/0x600 mm/slub.c:5676 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] kernfs_fop_open+0x38c/0xd20 fs/kernfs/file.c:648 do_dentry_open+0x80e/0x1360 fs/open.c:1000 vfs_open_consume+0x4a/0x350 fs/open.c:1131 do_open fs/namei.c:4851 [inline] path_openat+0x16fc/0x20f0 fs/namei.c:5016 do_file_open+0x23e/0x4a0 fs/namei.c:5045 do_sys_openat2+0x115/0x200 fs/open.c:1443 do_sys_open fs/open.c:1449 [inline] __do_sys_openat fs/open.c:1465 [inline] __se_sys_openat fs/open.c:1460 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1460 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x16a/0x530 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888057dd4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888057dd4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888057dd4200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888057dd4280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888057dd4300: fb fb fb fb fb fb fb fb fb fb fb fb 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