em28xx 4-1:0.132: Closing input extension ================================================================== BUG: KASAN: slab-use-after-free in media_device_unregister drivers/media/mc/mc-device.c:804 [inline] BUG: KASAN: slab-use-after-free in media_device_unregister+0x598/0x5c0 drivers/media/mc/mc-device.c:782 Read of size 8 at addr ffff88811b3e8210 by task kworker/1:3/5212 CPU: 1 UID: 0 PID: 5212 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 media_device_unregister drivers/media/mc/mc-device.c:804 [inline] media_device_unregister+0x598/0x5c0 drivers/media/mc/mc-device.c:782 em28xx_unregister_media_device drivers/media/usb/em28xx/em28xx-cards.c:3511 [inline] em28xx_release_resources+0xb2/0x2d0 drivers/media/usb/em28xx/em28xx-cards.c:3532 em28xx_usb_disconnect+0x1de/0x610 drivers/media/usb/em28xx/em28xx-cards.c:4201 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:571 [inline] device_remove+0x125/0x170 drivers/base/dd.c:563 __device_release_driver drivers/base/dd.c:1274 [inline] device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1297 bus_remove_device+0x22f/0x420 drivers/base/bus.c:579 device_del+0x396/0x9f0 drivers/base/core.c:3878 usb_disable_device+0x355/0x7d0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x9c0 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+0x1aa2/0x5060 drivers/usb/core/hub.c:5953 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x56d/0x700 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 15556: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:417 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] em28xx_v4l2_init+0x114/0x4080 drivers/media/usb/em28xx/em28xx-video.c:2532 em28xx_init_extension+0x13a/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x56d/0x700 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 15556: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 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+0x43/0x70 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2539 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x288/0x670 mm/slub.c:6837 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline] kref_put include/linux/kref.h:65 [inline] em28xx_v4l2_init+0x22b5/0x4080 drivers/media/usb/em28xx/em28xx-video.c:2901 em28xx_init_extension+0x13a/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x56d/0x700 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 ffff88811b3e8000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 528 bytes inside of freed 8192-byte region [ffff88811b3e8000, ffff88811b3ea000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11b3e8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x200000000000040(head|node=0|zone=2) page_type: f5(slab) raw: 0200000000000040 ffff888100042280 ffffea00046d1e00 dead000000000003 raw: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000 head: 0200000000000040 ffff888100042280 ffffea00046d1e00 dead000000000003 head: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000 head: 0200000000000003 ffffea00046cfa01 00000000ffffffff 00000000ffffffff head: 0000000000000000 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 2963, tgid 2963 (syz-executor), ts 37906992871, free_ts 37792701972 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x1003/0x2dc0 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x259/0x21f0 mm/page_alloc.c:5183 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3055 [inline] allocate_slab mm/slub.c:3228 [inline] new_slab+0x24a/0x360 mm/slub.c:3282 ___slab_alloc+0xdb7/0x1a70 mm/slub.c:4651 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4770 __slab_alloc_node mm/slub.c:4846 [inline] slab_alloc_node mm/slub.c:5268 [inline] __do_kmalloc_node mm/slub.c:5641 [inline] __kmalloc_node_track_caller_noprof+0x4a5/0x850 mm/slub.c:5751 kmemdup_noprof+0x29/0x60 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:765 [inline] ipv4_sysctl_init_net+0x3e/0x350 net/ipv4/sysctl_net_ipv4.c:1626 ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137 setup_net+0x100/0x390 net/core/net_namespace.c:445 copy_net_ns+0x2f8/0x690 net/core/net_namespace.c:580 create_new_namespaces+0x3ea/0xa90 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:218 ksys_unshare+0x45b/0xa40 kernel/fork.c:3129 page last free pid 2998 tgid 2998 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x78f/0x1000 mm/page_alloc.c:2906 discard_slab mm/slub.c:3326 [inline] __put_partials+0x130/0x170 mm/slub.c:3872 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4970 [inline] slab_alloc_node mm/slub.c:5280 [inline] kmem_cache_alloc_noprof+0x260/0x6c0 mm/slub.c:5287 mt_alloc_one lib/maple_tree.c:172 [inline] mas_alloc_nodes lib/maple_tree.c:1108 [inline] mas_preallocate+0xe6a/0x11f0 lib/maple_tree.c:5192 vma_iter_prealloc mm/vma.h:442 [inline] __split_vma+0x34a/0x1040 mm/vma.c:528 split_vma mm/vma.c:598 [inline] vma_modify+0xadb/0x21a0 mm/vma.c:1631 vma_modify_flags+0x1b0/0x250 mm/vma.c:1649 mprotect_fixup+0x1df/0xb40 mm/mprotect.c:816 do_mprotect_pkey+0x9bc/0xd40 mm/mprotect.c:990 __do_sys_mprotect mm/mprotect.c:1011 [inline] __se_sys_mprotect mm/mprotect.c:1008 [inline] __x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:1008 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88811b3e8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811b3e8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88811b3e8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88811b3e8280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811b3e8300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================