syzbot

em28xx 5-1:0.0: Closing input extension
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BUG: KASAN: slab-use-after-free in media_device_unregister+0x154/0x470
Read of size 8 at addr ffff888022fd4210 by task kworker/1:2/58

CPU: 1 UID: 0 PID: 58 Comm: kworker/1:2 Not tainted 6.11.0-rc4-syzkaller-00019-gb311c1b497e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 media_device_unregister+0x154/0x470
 em28xx_unregister_media_device drivers/media/usb/em28xx/em28xx-cards.c:3511 [inline]
 em28xx_release_resources+0xa7/0x230 drivers/media/usb/em28xx/em28xx-cards.c:3532
 em28xx_usb_disconnect+0x1cc/0x530 drivers/media/usb/em28xx/em28xx-cards.c:4201
 usb_unbind_interface+0x25e/0x940 drivers/usb/core/driver.c:461
 device_remove drivers/base/dd.c:568 [inline]
 __device_release_driver drivers/base/dd.c:1272 [inline]
 device_release_driver_internal+0x503/0x7c0 drivers/base/dd.c:1295
 bus_remove_device+0x34f/0x420 drivers/base/bus.c:574
 device_del+0x57a/0x9b0 drivers/base/core.c:3871
 usb_disable_device+0x3bf/0x850 drivers/usb/core/message.c:1418
 usb_disconnect+0x340/0x950 drivers/usb/core/hub.c:2304
 hub_port_connect drivers/usb/core/hub.c:5361 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
 port_event drivers/usb/core/hub.c:5821 [inline]
 hub_event+0x1ebc/0x5150 drivers/usb/core/hub.c:5903
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 46:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4189
 kmalloc_noprof include/linux/slab.h:681 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 em28xx_v4l2_init+0xfd/0x2f40 drivers/media/usb/em28xx/em28xx-video.c:2534
 em28xx_init_extension+0x120/0x1c0 drivers/media/usb/em28xx/em28xx-core.c:1117
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 46:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2252 [inline]
 slab_free mm/slub.c:4473 [inline]
 kfree+0x149/0x360 mm/slub.c:4594
 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2120 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_v4l2_init+0x16d7/0x2f40 drivers/media/usb/em28xx/em28xx-video.c:2903
 em28xx_init_extension+0x120/0x1c0 drivers/media/usb/em28xx/em28xx-core.c:1117
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

The buggy address belongs to the object at ffff888022fd4000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 528 bytes inside of
 freed 8192-byte region [ffff888022fd4000, ffff888022fd6000)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x22fd0
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: 0xfdffffff(slab)
raw: 00fff00000000040 ffff888015842280 ffffea0001c4b000 0000000000000006
raw: 0000000000000000 0000000080020002 00000001fdffffff 0000000000000000
head: 00fff00000000040 ffff888015842280 ffffea0001c4b000 0000000000000006
head: 0000000000000000 0000000080020002 00000001fdffffff 0000000000000000
head: 00fff00000000003 ffffea00008bf401 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4894, tgid 4894 (dhcpcd), ts 229957180461, free_ts 229957129915
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493
 prep_new_page mm/page_alloc.c:1501 [inline]
 get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3439
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2321
 allocate_slab+0x5a/0x2f0 mm/slub.c:2484
 new_slab mm/slub.c:2537 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3723
 __slab_alloc+0x58/0xa0 mm/slub.c:3813
 __slab_alloc_node mm/slub.c:3866 [inline]
 slab_alloc_node mm/slub.c:4025 [inline]
 __do_kmalloc_node mm/slub.c:4157 [inline]
 __kmalloc_node_track_caller_noprof+0x281/0x440 mm/slub.c:4177
 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:605
 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:674
 alloc_skb include/linux/skbuff.h:1320 [inline]
 netlink_dump+0x1f7/0xd80 net/netlink/af_netlink.c:2291
 __netlink_dump_start+0x5a2/0x790 net/netlink/af_netlink.c:2440
 netlink_dump_start include/linux/netlink.h:339 [inline]
 rtnetlink_dump_start net/core/rtnetlink.c:6536 [inline]
 rtnetlink_rcv_msg+0xb3d/0xcf0 net/core/rtnetlink.c:6603
 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901
page last free pid 4894 tgid 4894 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1094 [inline]
 free_unref_page+0xd22/0xea0 mm/page_alloc.c:2612
 __slab_free+0x31b/0x3d0 mm/slub.c:4384
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3988 [inline]
 slab_alloc_node mm/slub.c:4037 [inline]
 kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4080
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:664
 netlink_sendmsg+0x638/0xcb0 net/netlink/af_netlink.c:1876
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 __sys_sendto+0x3a4/0x4f0 net/socket.c:2204
 __do_sys_sendto net/socket.c:2216 [inline]
 __se_sys_sendto net/socket.c:2212 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2212
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888022fd4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888022fd4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888022fd4200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff888022fd4280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888022fd4300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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