device veth0_macvtap left promiscuous mode device veth1_vlan left promiscuous mode device veth0_vlan left promiscuous mode ================================================================== BUG: KASAN: use-after-free in tcp_orphan_retries net/ipv4/tcp_timer.c:127 [inline] BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:369 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0xa4b/0xa60 net/ipv4/tcp_timer.c:597 Read of size 4 at addr ffff888096c108e8 by task kworker/u4:8/26356 CPU: 1 PID: 26356 Comm: kworker/u4:8 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load4_noabort+0x88/0x90 mm/kasan/report.c:432 tcp_orphan_retries net/ipv4/tcp_timer.c:127 [inline] tcp_probe_timer net/ipv4/tcp_timer.c:369 [inline] tcp_write_timer_handler+0xa4b/0xa60 net/ipv4/tcp_timer.c:597 tcp_write_timer+0x103/0x1b0 net/ipv4/tcp_timer.c:613 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1092 do_softirq.part.0+0x160/0x1c0 kernel/softirq.c:336 do_softirq kernel/softirq.c:328 [inline] __local_bh_enable_ip+0x20e/0x270 kernel/softirq.c:189 spin_unlock_bh include/linux/spinlock.h:374 [inline] fib6_run_gc+0x1d1/0x2d0 net/ipv6/ip6_fib.c:2140 ndisc_netdev_event+0x394/0x4a0 net/ipv6/ndisc.c:1789 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93 call_netdevice_notifiers net/core/dev.c:1762 [inline] dev_close_many+0x323/0x670 net/core/dev.c:1514 rollback_registered_many+0x2f7/0xe70 net/core/dev.c:8173 unregister_netdevice_many.part.0+0x1a/0x300 net/core/dev.c:9324 unregister_netdevice_many net/core/dev.c:9323 [inline] default_device_exit_batch+0x2fa/0x3c0 net/core/dev.c:9795 ops_exit_list+0xf9/0x150 net/core/net_namespace.c:156 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:554 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Allocated by task 8109: kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 kmem_cache_zalloc include/linux/slab.h:699 [inline] net_alloc net/core/net_namespace.c:386 [inline] copy_net_ns+0x106/0x340 net/core/net_namespace.c:426 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2542 __do_sys_unshare kernel/fork.c:2610 [inline] __se_sys_unshare kernel/fork.c:2608 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2608 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 26356: __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 net_free net/core/net_namespace.c:402 [inline] net_drop_ns+0x73/0x90 net/core/net_namespace.c:409 cleanup_net+0x64c/0x8b0 net/core/net_namespace.c:572 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 The buggy address belongs to the object at ffff888096c10180 which belongs to the cache net_namespace of size 8704 The buggy address is located 1896 bytes inside of 8704-byte region [ffff888096c10180, ffff888096c12380) The buggy address belongs to the page: page:ffffea00025b0400 count:1 mapcount:0 mapping:ffff88823b843e00 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea00027d1908 ffffea0002744008 ffff88823b843e00 raw: 0000000000000000 ffff888096c10180 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888096c10780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888096c10800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888096c10880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888096c10900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888096c10980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================