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BUG: KASAN: use-after-free in read_pnet include/net/net_namespace.h:414 [inline]
BUG: KASAN: use-after-free in dev_net include/linux/netdevice.h:2738 [inline]
BUG: KASAN: use-after-free in nf_hook_entry_head+0x2fe/0x310 net/netfilter/core.c:319
Read of size 8 at addr ffff88802d63c108 by task kworker/u32:22/6245

CPU: 2 UID: 0 PID: 6245 Comm: kworker/u32:22 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 __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
 read_pnet include/net/net_namespace.h:414 [inline]
 dev_net include/linux/netdevice.h:2738 [inline]
 nf_hook_entry_head+0x2fe/0x310 net/netfilter/core.c:319
 __nf_unregister_net_hook+0x7e/0x660 net/netfilter/core.c:491
 nf_unregister_net_hook+0xd5/0x110 net/netfilter/core.c:536
 nft_unregister_flowtable_ops net/netfilter/nf_tables_api.c:8977 [inline]
 __nft_unregister_flowtable_net_hooks+0xfc/0x3f0 net/netfilter/nf_tables_api.c:8992
 __nft_release_hook+0x26e/0x350 net/netfilter/nf_tables_api.c:11985
 __nft_release_hooks net/netfilter/nf_tables_api.c:11999 [inline]
 nf_tables_pre_exit_net+0xc5/0x120 net/netfilter/nf_tables_api.c:12150
 ops_pre_exit_list net/core/net_namespace.c:161 [inline]
 ops_undo_list+0x187/0xab0 net/core/net_namespace.c:234
 cleanup_net+0x41b/0x830 net/core/net_namespace.c:696
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802d63f0c0 pfn:0x2d63c
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f0(buddy)
raw: 00fff00000000000 ffffea00015e0608 ffffea00015c5b08 0000000000000000
raw: ffff88802d63f0c0 0000000000000002 00000000f0000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL), pid 23674, tgid 23673 (syz.8.5160), ts 433081851557, free_ts 433845905060
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 __alloc_pages_noprof mm/page_alloc.c:5244 [inline]
 alloc_pages_bulk_noprof+0x77a/0x1410 mm/page_alloc.c:5164
 ___alloc_pages_bulk mm/kasan/shadow.c:345 [inline]
 __kasan_populate_vmalloc_do mm/kasan/shadow.c:370 [inline]
 __kasan_populate_vmalloc+0xfb/0x220 mm/kasan/shadow.c:424
 kasan_populate_vmalloc include/linux/kasan.h:579 [inline]
 alloc_vmap_area+0x98d/0x2a50 mm/vmalloc.c:2124
 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3219
 __vmalloc_node_range_noprof+0x247/0x16b0 mm/vmalloc.c:4011
 vmalloc_user_noprof+0x9e/0xe0 mm/vmalloc.c:4205
 vb2_vmalloc_alloc+0x135/0x410 drivers/media/common/videobuf2/videobuf2-vmalloc.c:47
 __vb2_buf_mem_alloc drivers/media/common/videobuf2/videobuf2-core.c:242 [inline]
 __vb2_queue_alloc+0x8c9/0x1280 drivers/media/common/videobuf2/videobuf2-core.c:523
 vb2_core_reqbufs+0xa90/0xfe0 drivers/media/common/videobuf2/videobuf2-core.c:964
 __vb2_init_fileio+0x3f1/0x1100 drivers/media/common/videobuf2/videobuf2-core.c:2895
 __vb2_perform_fileio+0x9c2/0x1660 drivers/media/common/videobuf2/videobuf2-core.c:3041
 vb2_fop_write+0x207/0x3f0 drivers/media/common/videobuf2/videobuf2-v4l2.c:1190
 v4l2_write+0x229/0x360 drivers/media/v4l2-core/v4l2-dev.c:333
page last free pid 34 tgid 34 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943
 kasan_depopulate_vmalloc_pte+0x5b/0x80 mm/kasan/shadow.c:484
 apply_to_pte_range mm/memory.c:3182 [inline]
 apply_to_pmd_range mm/memory.c:3226 [inline]
 apply_to_pud_range mm/memory.c:3262 [inline]
 apply_to_p4d_range mm/memory.c:3298 [inline]
 __apply_to_page_range+0xac1/0x13f0 mm/memory.c:3334
 __kasan_release_vmalloc+0xd1/0xe0 mm/kasan/shadow.c:602
 kasan_release_vmalloc include/linux/kasan.h:592 [inline]
 kasan_release_vmalloc_node mm/vmalloc.c:2282 [inline]
 purge_vmap_node+0x1ba/0xad0 mm/vmalloc.c:2299
 __purge_vmap_area_lazy+0x9d2/0xc00 mm/vmalloc.c:2389
 drain_vmap_area_work+0x27/0x40 mm/vmalloc.c:2423
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Memory state around the buggy address:
 ffff88802d63c000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802d63c080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88802d63c100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                      ^
 ffff88802d63c180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802d63c200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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