================================================================== BUG: KCSAN: data-race in ip6_tnl_start_xmit / ip6_tnl_start_xmit read to 0xffff888134802160 of 8 bytes by task 2980 on cpu 0: ip6_tnl_start_xmit+0x873/0xa90 net/ipv6/ip6_tunnel.c:1438 __netdev_start_xmit include/linux/netdevice.h:4994 [inline] netdev_start_xmit include/linux/netdevice.h:5008 [inline] xmit_one+0x105/0x2f0 net/core/dev.c:3590 dev_hard_start_xmit net/core/dev.c:3606 [inline] __dev_queue_xmit+0x869/0xf70 net/core/dev.c:4229 dev_queue_xmit+0x13/0x20 net/core/dev.c:4262 neigh_connected_output+0x264/0x290 net/core/neighbour.c:1551 neigh_output include/net/neighbour.h:527 [inline] ip6_finish_output2+0x9be/0xbb0 net/ipv6/ip6_output.c:126 ip6_fragment+0x1197/0x13e0 net/ipv6/ip6_output.c:966 __ip6_finish_output net/ipv6/ip6_output.c:189 [inline] ip6_finish_output+0x463/0x4c0 net/ipv6/ip6_output.c:201 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:224 dst_output include/net/dst.h:450 [inline] ip6_local_out+0x60/0x80 net/ipv6/output_core.c:161 ip6_send_skb net/ipv6/ip6_output.c:1912 [inline] ip6_push_pending_frames+0xb6/0x170 net/ipv6/ip6_output.c:1932 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline] rawv6_sendmsg+0x1324/0x13f0 net/ipv6/raw.c:956 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] ____sys_sendmsg+0x39a/0x510 net/socket.c:2409 ___sys_sendmsg net/socket.c:2463 [inline] __sys_sendmsg+0x195/0x230 net/socket.c:2492 __do_sys_sendmsg net/socket.c:2501 [inline] __se_sys_sendmsg net/socket.c:2499 [inline] __x64_sys_sendmsg+0x42/0x50 net/socket.c:2499 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae write to 0xffff888134802160 of 8 bytes by task 2986 on cpu 1: ip6_tnl_start_xmit+0x885/0xa90 net/ipv6/ip6_tunnel.c:1438 __netdev_start_xmit include/linux/netdevice.h:4994 [inline] netdev_start_xmit include/linux/netdevice.h:5008 [inline] xmit_one+0x105/0x2f0 net/core/dev.c:3590 dev_hard_start_xmit net/core/dev.c:3606 [inline] __dev_queue_xmit+0x869/0xf70 net/core/dev.c:4229 dev_queue_xmit+0x13/0x20 net/core/dev.c:4262 neigh_connected_output+0x264/0x290 net/core/neighbour.c:1551 neigh_output include/net/neighbour.h:527 [inline] ip6_finish_output2+0x9be/0xbb0 net/ipv6/ip6_output.c:126 ip6_fragment+0x1197/0x13e0 net/ipv6/ip6_output.c:966 __ip6_finish_output net/ipv6/ip6_output.c:189 [inline] ip6_finish_output+0x463/0x4c0 net/ipv6/ip6_output.c:201 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:224 dst_output include/net/dst.h:450 [inline] ip6_local_out+0x60/0x80 net/ipv6/output_core.c:161 ip6_send_skb net/ipv6/ip6_output.c:1912 [inline] ip6_push_pending_frames+0xb6/0x170 net/ipv6/ip6_output.c:1932 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline] rawv6_sendmsg+0x1324/0x13f0 net/ipv6/raw.c:956 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] ____sys_sendmsg+0x39a/0x510 net/socket.c:2409 ___sys_sendmsg net/socket.c:2463 [inline] __sys_sendmsg+0x195/0x230 net/socket.c:2492 __do_sys_sendmsg net/socket.c:2501 [inline] __se_sys_sendmsg net/socket.c:2499 [inline] __x64_sys_sendmsg+0x42/0x50 net/socket.c:2499 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000000000014ce -> 0x00000000000014cf Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 2986 Comm: syz-executor.1 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================