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BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:791 [inline]
BUG: KASAN: use-after-free in detach_timer kernel/time/timer.c:824 [inline]
BUG: KASAN: use-after-free in detach_if_pending+0x188/0x360 kernel/time/timer.c:841
Write of size 8 at addr ffff8881ea6a71c8 by task kworker/u4:2/103

CPU: 1 PID: 103 Comm: kworker/u4:2 Not tainted 5.4.268-syzkaller-00012-gd0d34dcb02cc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x241 lib/dump_stack.c:118
 print_address_description+0x8c/0x600 mm/kasan/report.c:384
 __kasan_report+0xf3/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 __hlist_del include/linux/list.h:791 [inline]
 detach_timer kernel/time/timer.c:824 [inline]
 detach_if_pending+0x188/0x360 kernel/time/timer.c:841
 try_to_del_timer_sync kernel/time/timer.c:1238 [inline]
 del_timer_sync+0x13c/0x230 kernel/time/timer.c:1379
 can_pernet_exit+0x36/0xc0 net/can/af_can.c:832
 ops_exit_list net/core/net_namespace.c:179 [inline]
 cleanup_net+0x665/0xc90 net/core/net_namespace.c:609
 process_one_work+0x765/0xd20 kernel/workqueue.c:2290
 worker_thread+0xaef/0x1470 kernel/workqueue.c:2436
 kthread+0x2da/0x360 kernel/kthread.c:288
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354

Allocated by task 358:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 __alloc_skb+0x7a/0x4d0 net/core/skbuff.c:198
 alloc_skb_fclone include/linux/skbuff.h:1130 [inline]
 sk_stream_alloc_skb+0x1f4/0xa70 net/ipv4/tcp.c:888
 tcp_sendmsg_locked+0xe07/0x3810 net/ipv4/tcp.c:1297
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1447
 sock_sendmsg_nosec net/socket.c:638 [inline]
 __sock_sendmsg net/socket.c:650 [inline]
 sock_write_iter+0x344/0x470 net/socket.c:1009
 call_write_iter include/linux/fs.h:1983 [inline]
 new_sync_write fs/read_write.c:483 [inline]
 __vfs_write+0x5d3/0x750 fs/read_write.c:496
 vfs_write+0x206/0x4e0 fs/read_write.c:558
 ksys_write+0x199/0x2c0 fs/read_write.c:611
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Freed by task 3835:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook mm/slub.c:1494 [inline]
 slab_free mm/slub.c:3080 [inline]
 kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096
 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3206 [inline]
 tcp_ack+0x206c/0x6090 net/ipv4/tcp_input.c:3757
 tcp_rcv_established+0xd16/0x1a80 net/ipv4/tcp_input.c:5715
 tcp_v4_do_rcv+0x3a9/0x770 net/ipv4/tcp_ipv4.c:1589
 tcp_v4_rcv+0x219a/0x26f0 net/ipv4/tcp_ipv4.c:1971
 ip_protocol_deliver_rcu+0x2e0/0x630 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 ip_local_deliver+0x2c6/0x5a0 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:444 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:541 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:579 [inline]
 ip_sublist_rcv+0xc02/0xc80 net/ipv4/ip_input.c:587
 ip_list_rcv+0x477/0x4c0 net/ipv4/ip_input.c:621
 __netif_receive_skb_list_ptype net/core/dev.c:5015 [inline]
 __netif_receive_skb_list_core+0x6dd/0x8f0 net/core/dev.c:5063
 __netif_receive_skb_list net/core/dev.c:5115 [inline]
 netif_receive_skb_list_internal+0x944/0xc90 net/core/dev.c:5210
 gro_normal_list net/core/dev.c:5321 [inline]
 napi_complete_done+0x20a/0x580 net/core/dev.c:6052
 virtqueue_napi_complete drivers/net/virtio_net.c:357 [inline]
 virtnet_poll+0xb61/0x1250 drivers/net/virtio_net.c:1516
 napi_poll net/core/dev.c:6367 [inline]
 net_rx_action+0x53f/0x1160 net/core/dev.c:6435
 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292

The buggy address belongs to the object at ffff8881ea6a7180
 which belongs to the cache skbuff_fclone_cache of size 488
The buggy address is located 72 bytes inside of
 488-byte region [ffff8881ea6a7180, ffff8881ea6a7368)
The buggy address belongs to the page:
page:ffffea0007a9a980 refcount:1 mapcount:0 mapping:ffff8881f1dcc780 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f1dcc780
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4891
 alloc_slab_page+0x39/0x3c0 mm/slub.c:343
 allocate_slab mm/slub.c:1683 [inline]
 new_slab+0x97/0x440 mm/slub.c:1749
 new_slab_objects mm/slub.c:2505 [inline]
 ___slab_alloc+0x2fe/0x490 mm/slub.c:2667
 __slab_alloc+0x62/0xa0 mm/slub.c:2707
 slab_alloc_node mm/slub.c:2792 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0x109/0x250 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 __alloc_skb+0x7a/0x4d0 net/core/skbuff.c:198
 alloc_skb_fclone include/linux/skbuff.h:1130 [inline]
 sk_stream_alloc_skb+0x1f4/0xa70 net/ipv4/tcp.c:888
 tcp_sendmsg_locked+0xe07/0x3810 net/ipv4/tcp.c:1297
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1447
 sock_sendmsg_nosec net/socket.c:638 [inline]
 __sock_sendmsg net/socket.c:650 [inline]
 sock_write_iter+0x344/0x470 net/socket.c:1009
 call_write_iter include/linux/fs.h:1983 [inline]
 new_sync_write fs/read_write.c:483 [inline]
 __vfs_write+0x5d3/0x750 fs/read_write.c:496
 vfs_write+0x206/0x4e0 fs/read_write.c:558
 ksys_write+0x199/0x2c0 fs/read_write.c:611
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 free_pcp_prepare mm/page_alloc.c:1233 [inline]
 free_unref_page_prepare+0x297/0x380 mm/page_alloc.c:3085
 free_unref_page_list+0x10a/0x590 mm/page_alloc.c:3154
 release_pages+0xad8/0xb20 mm/swap.c:842
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:189 [inline]
 tlb_flush_mmu mm/mmu_gather.c:196 [inline]
 tlb_finish_mmu+0x177/0x320 mm/mmu_gather.c:277
 exit_mmap+0x2dc/0x520 mm/mmap.c:3188
 __mmput+0x8e/0x2c0 kernel/fork.c:1101
 exit_mm kernel/exit.c:536 [inline]
 do_exit+0xc08/0x2bc0 kernel/exit.c:846
 do_group_exit+0x138/0x300 kernel/exit.c:982
 get_signal+0xdb1/0x1440 kernel/signal.c:2735
 do_signal+0xb0/0x11f0 arch/x86/kernel/signal.c:809
 exit_to_usermode_loop+0xc0/0x1a0 arch/x86/entry/common.c:159
 prepare_exit_to_usermode+0x199/0x200 arch/x86/entry/common.c:194
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881ea6a7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff8881ea6a7100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881ea6a7180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff8881ea6a7200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881ea6a7280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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