syzbot

em28xx 5-1:0.132: Closing input extension
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BUG: KASAN: use-after-free in media_device_unregister+0x132/0x3f0
Read of size 8 at addr ffff8880589fc210 by task kworker/0:0/7

CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.1.125-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:427
 kasan_report+0x136/0x160 mm/kasan/report.c:531
 media_device_unregister+0x132/0x3f0
 em28xx_unregister_media_device drivers/media/usb/em28xx/em28xx-cards.c:3459 [inline]
 em28xx_release_resources+0xa6/0x230 drivers/media/usb/em28xx/em28xx-cards.c:3480
 em28xx_usb_disconnect+0x1c4/0x520 drivers/media/usb/em28xx/em28xx-cards.c:4149
 usb_unbind_interface+0x1cd/0x840 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:550 [inline]
 __device_release_driver drivers/base/dd.c:1260 [inline]
 device_release_driver_internal+0x59e/0x880 drivers/base/dd.c:1286
 bus_remove_device+0x2e5/0x400 drivers/base/bus.c:531
 device_del+0x6e2/0xbd0 drivers/base/core.c:3884
 usb_disable_device+0x3b8/0x840 drivers/usb/core/message.c:1414
 usb_disconnect+0x33c/0x8c0 drivers/usb/core/hub.c:2275
 hub_port_connect drivers/usb/core/hub.c:5323 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5619 [inline]
 port_event drivers/usb/core/hub.c:5775 [inline]
 hub_event+0x1f78/0x5730 drivers/usb/core/hub.c:5857
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 process_scheduled_works kernel/workqueue.c:2355 [inline]
 worker_thread+0xd04/0x1200 kernel/workqueue.c:2441
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 4249:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 em28xx_v4l2_init+0x103/0x2db0 drivers/media/usb/em28xx/em28xx-video.c:2532
 em28xx_init_extension+0x11b/0x1c0 drivers/media/usb/em28xx/em28xx-core.c:1116
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 process_scheduled_works kernel/workqueue.c:2355 [inline]
 worker_thread+0xcb2/0x1200 kernel/workqueue.c:2444
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 4249:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_v4l2_init+0x1604/0x2db0 drivers/media/usb/em28xx/em28xx-video.c:2901
 em28xx_init_extension+0x11b/0x1c0 drivers/media/usb/em28xx/em28xx-core.c:1116
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 process_scheduled_works kernel/workqueue.c:2355 [inline]
 worker_thread+0xcb2/0x1200 kernel/workqueue.c:2444
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff8880589fc000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 528 bytes inside of
 8192-byte region [ffff8880589fc000, ffff8880589fe000)

The buggy address belongs to the physical page:
page:ffffea0001627e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x589f8
head:ffffea0001627e00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888017c42280
raw: 0000000000000000 0000000080020002 00000001ffffffff 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 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 19303, tgid 19300 (syz.0.4570), ts 1274614985504, free_ts 1274545020997
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4328
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5605
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa1/0x230 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x26b/0x530 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x594/0x5d0 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_number_perm+0x21f/0x7f0 security/tomoyo/file.c:723
 tomoyo_path_mknod+0x172/0x1b0 security/tomoyo/tomoyo.c:239
 security_path_mknod+0xf1/0x150 security/security.c:1166
 may_o_create fs/namei.c:3304 [inline]
 lookup_open fs/namei.c:3445 [inline]
 open_last_lookups fs/namei.c:3550 [inline]
 path_openat+0xc29/0x2e60 fs/namei.c:3780
 do_filp_open+0x230/0x480 fs/namei.c:3810
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1318
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x12a6/0x15b0 mm/page_alloc.c:3384
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3479
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586
 put_cpu_partial+0x17b/0x250 mm/slub.c:2662
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 kmem_cache_zalloc include/linux/slab.h:689 [inline]
 jbd2_alloc_handle include/linux/jbd2.h:1602 [inline]
 new_handle fs/jbd2/transaction.c:476 [inline]
 jbd2__journal_start+0x144/0x5c0 fs/jbd2/transaction.c:503
 __ext4_journal_start_sb+0x19b/0x410 fs/ext4/ext4_jbd2.c:105
 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
 ext4_dirty_inode+0x8b/0x100 fs/ext4/inode.c:6086
 __mark_inode_dirty+0x331/0xf80 fs/fs-writeback.c:2433
 generic_update_time fs/inode.c:1946 [inline]
 inode_update_time fs/inode.c:1959 [inline]
 __file_update_time+0x221/0x240 fs/inode.c:2147
 file_update_time+0x34c/0x3c0 fs/inode.c:2178
 ext4_page_mkwrite+0x1c4/0x10d0 fs/ext4/inode.c:6207

Memory state around the buggy address:
 ffff8880589fc100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880589fc180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880589fc200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff8880589fc280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880589fc300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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