Dead loop on virtual device ip6_vti0, fix it urgently! ===================================================== BUG: KMSAN: uninit-value in decode_session6 net/xfrm/xfrm_policy.c:3407 [inline] BUG: KMSAN: uninit-value in __xfrm_decode_session+0x18ec/0x33e0 net/xfrm/xfrm_policy.c:3482 CPU: 1 PID: 5632 Comm: syz-executor.2 Not tainted 5.4.0-rc5+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x191/0x1f0 lib/dump_stack.c:113 kmsan_report+0x128/0x220 mm/kmsan/kmsan_report.c:108 __msan_warning+0x73/0xe0 mm/kmsan/kmsan_instr.c:245 decode_session6 net/xfrm/xfrm_policy.c:3407 [inline] __xfrm_decode_session+0x18ec/0x33e0 net/xfrm/xfrm_policy.c:3482 vti_tunnel_xmit+0x395/0x1db0 net/ipv4/ip_vti.c:263 __netdev_start_xmit include/linux/netdevice.h:4420 [inline] netdev_start_xmit include/linux/netdevice.h:4434 [inline] xmit_one net/core/dev.c:3280 [inline] dev_hard_start_xmit+0x51a/0xab0 net/core/dev.c:3296 sch_direct_xmit+0x56c/0x18c0 net/sched/sch_generic.c:314 qdisc_restart net/sched/sch_generic.c:377 [inline] __qdisc_run+0x15f1/0x33a0 net/sched/sch_generic.c:385 __dev_xmit_skb net/core/dev.c:3537 [inline] __dev_queue_xmit+0x23d1/0x4200 net/core/dev.c:3842 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3906 neigh_direct_output+0x42/0x50 net/core/neighbour.c:1530 neigh_output include/net/neighbour.h:511 [inline] ip6_finish_output2+0x2129/0x2670 net/ipv6/ip6_output.c:116 __ip6_finish_output+0x83d/0x8f0 net/ipv6/ip6_output.c:142 ip6_finish_output+0x2db/0x420 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0x5d3/0x720 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] ip6_local_out+0x164/0x1d0 net/ipv6/output_core.c:179 ip6_send_skb+0xfa/0x390 net/ipv6/ip6_output.c:1795 udp_v6_send_skb+0x1851/0x1eb0 net/ipv6/udp.c:1173 udpv6_sendmsg+0x434c/0x46a0 net/ipv6/udp.c:1471 inet6_sendmsg+0x276/0x2e0 net/ipv6/af_inet6.c:576 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg net/socket.c:657 [inline] ___sys_sendmsg+0xe89/0x1590 net/socket.c:2311 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2413 __do_sys_sendmmsg net/socket.c:2442 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2439 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2439 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x45a219 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0bf8f78c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045a219 RDX: 000000000000000a RSI: 0000000020000f40 RDI: 0000000000000005 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0bf8f796d4 R13: 00000000004c7f9d R14: 00000000004de3c8 R15: 00000000ffffffff Uninit was created at: kmsan_save_stack_with_flags+0x3f/0x90 mm/kmsan/kmsan.c:151 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:362 [inline] kmsan_alloc_page+0x153/0x360 mm/kmsan/kmsan_shadow.c:391 __alloc_pages_nodemask+0x149d/0x60c0 mm/page_alloc.c:4796 alloc_pages_current+0x68d/0x9a0 mm/mempolicy.c:2188 alloc_pages include/linux/gfp.h:511 [inline] alloc_slab_page+0x10e/0x12c0 mm/slub.c:1536 allocate_slab mm/slub.c:1681 [inline] new_slab+0x2ca/0x1990 mm/slub.c:1747 new_slab_objects mm/slub.c:2498 [inline] ___slab_alloc+0x1423/0x1fb0 mm/slub.c:2649 __slab_alloc mm/slub.c:2689 [inline] slab_alloc_node mm/slub.c:2763 [inline] slab_alloc mm/slub.c:2808 [inline] kmem_cache_alloc+0xadf/0xd20 mm/slub.c:2813 sk_prot_alloc+0xed/0x5c0 net/core/sock.c:1599 sk_alloc+0xf3/0xb60 net/core/sock.c:1659 inet_create+0x7d4/0x1380 net/ipv4/af_inet.c:321 __sock_create+0x8ee/0xf00 net/socket.c:1418 sock_create_kern+0xf0/0x100 net/socket.c:1487 inet_ctl_sock_create+0xfd/0x2f0 net/ipv4/af_inet.c:1629 dccp_v4_init_net+0xa1/0xe0 net/dccp/ipv4.c:1019 ops_init+0x2d3/0x730 net/core/net_namespace.c:137 setup_net+0x28e/0x12a0 net/core/net_namespace.c:335 copy_net_ns+0x73e/0x970 net/core/net_namespace.c:476 create_new_namespaces+0x8d8/0xda0 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0x25e/0x340 kernel/nsproxy.c:202 ksys_unshare+0x883/0x1110 kernel/fork.c:2829 __do_sys_unshare kernel/fork.c:2897 [inline] __se_sys_unshare+0x41/0x60 kernel/fork.c:2895 __x64_sys_unshare+0x32/0x50 kernel/fork.c:2895 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 =====================================================