usb 2-1: USB disconnect, device number 2
em28xx 2-1:246.0: Disconnecting em28xx #7
em28xx 2-1:246.0: Disconnecting em28xx
==================================================================
BUG: KASAN: slab-out-of-bounds in __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62
Read of size 8 at addr ffff88811eb00250 by task kworker/0:1/10

CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1d0 mm/kasan/report.c:595
 __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:223 [inline]
 list_del include/linux/list.h:237 [inline]
 em28xx_close_extension+0x10b/0x2b0 drivers/media/usb/em28xx/em28xx-core.c:1268
 em28xx_usb_disconnect.cold+0x13d/0x253 drivers/media/usb/em28xx/em28xx-cards.c:4423
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:621 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:613
 __device_release_driver drivers/base/dd.c:1352 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1375
 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:657
 device_del+0x376/0x9b0 drivers/base/core.c:3895
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
 usb_disconnect+0x2e2/0x9a0 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+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
 process_scheduled_works kernel/workqueue.c:3385 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 6788:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5295 [inline]
 __kmalloc_node_track_caller_noprof+0x306/0x800 mm/slub.c:5403
 kmalloc_reserve+0xe8/0x350 net/core/skbuff.c:635
 __alloc_skb+0x185/0x710 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xdd/0x760 net/core/skbuff.c:6734
 sock_alloc_send_pskb+0x801/0x980 net/core/sock.c:2998
 unix_dgram_sendmsg+0x3c7/0x1810 net/unix/af_unix.c:2141
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 sock_write_iter+0x524/0x5a0 net/socket.c:1254
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1070 fs/read_write.c:688
 ksys_write+0x1f8/0x250 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 2854:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x43/0x70 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:6246 [inline]
 kfree+0x204/0x650 mm/slub.c:6561
 skb_kfree_head net/core/skbuff.c:1075 [inline]
 skb_free_head+0xb9/0x160 net/core/skbuff.c:1087
 skb_release_data+0x6c5/0x8e0 net/core/skbuff.c:1114
 skb_release_all net/core/skbuff.c:1189 [inline]
 __kfree_skb net/core/skbuff.c:1203 [inline]
 consume_skb net/core/skbuff.c:1436 [inline]
 consume_skb+0xc4/0x110 net/core/skbuff.c:1430
 __unix_dgram_recvmsg+0x754/0xc30 net/unix/af_unix.c:2669
 unix_dgram_recvmsg+0xcd/0x100 net/unix/af_unix.c:2686
 sock_recvmsg_nosec net/socket.c:1137 [inline]
 sock_recvmsg+0x1a4/0x1f0 net/socket.c:1159
 ____sys_recvmsg+0x218/0x640 net/socket.c:2918
 ___sys_recvmsg+0x16a/0x1a0 net/socket.c:2960
 __sys_recvmsg+0x16d/0x220 net/socket.c:2993
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88811eb00000
 which belongs to the cache kmalloc-cg-512 of size 512
The buggy address is located 80 bytes to the right of
 allocated 512-byte region [ffff88811eb00000, ffff88811eb00200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11eb00
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88811eb00211
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff88810005d140 dead000000000100 dead000000000122
raw: 0000000000000000 0000040000100010 00000000f5000000 ffff88811eb00211
head: 0200000000000040 ffff88810005d140 dead000000000100 dead000000000122
head: 0000000000000000 0000040000100010 00000000f5000000 ffff88811eb00211
head: 0200000000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 2843, tgid 2843 (klogd), ts 155858789591, free_ts 155852403879
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858
 prep_new_page mm/page_alloc.c:1866 [inline]
 get_page_from_freelist+0xf34/0x3a90 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x273/0x28a0 mm/page_alloc.c:5226
 alloc_slab_page mm/slub.c:3278 [inline]
 allocate_slab mm/slub.c:3467 [inline]
 new_slab+0xa6/0x6b0 mm/slub.c:3525
 refill_objects+0x277/0x420 mm/slub.c:7251
 refill_sheaf mm/slub.c:2816 [inline]
 __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4651
 alloc_from_pcs mm/slub.c:4749 [inline]
 slab_alloc_node mm/slub.c:4883 [inline]
 __do_kmalloc_node mm/slub.c:5294 [inline]
 __kmalloc_node_track_caller_noprof+0x651/0x800 mm/slub.c:5403
 kmalloc_reserve+0xe8/0x350 net/core/skbuff.c:635
 __alloc_skb+0x185/0x710 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xdd/0x760 net/core/skbuff.c:6734
 sock_alloc_send_pskb+0x801/0x980 net/core/sock.c:2998
 unix_dgram_sendmsg+0x3c7/0x1810 net/unix/af_unix.c:2141
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x468/0x4b0 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0x7f0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 23 tgid 23 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1402 [inline]
 __free_frozen_pages+0x692/0xf10 mm/page_alloc.c:2943
 kref_put.constprop.0.isra.0+0x4d/0x6d include/linux/kref.h:65
 em28xx_usb_disconnect.cold+0x1b4/0x253 drivers/media/usb/em28xx/em28xx-cards.c:4430
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:621 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:613
 __device_release_driver drivers/base/dd.c:1352 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1375
 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:657
 device_del+0x376/0x9b0 drivers/base/core.c:3895
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
 usb_disconnect+0x2e2/0x9a0 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+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
 process_scheduled_works kernel/workqueue.c:3385 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x69a/0xc80 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:
 ffff88811eb00100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811eb00180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811eb00200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                 ^
 ffff88811eb00280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88811eb00300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================