================================================================== BUG: KCSAN: data-race in iptunnel_xmit / iptunnel_xmit write to 0xffff8880b3748140 of 8 bytes by task 32522 on cpu 0: iptunnel_xmit_stats include/net/ip_tunnels.h:459 [inline] iptunnel_xmit+0x435/0x4b0 net/ipv4/ip_tunnel_core.c:86 ip_tunnel_xmit+0x1099/0x11c0 net/ipv4/ip_tunnel.c:816 __gre_xmit net/ipv4/ip_gre.c:466 [inline] ipgre_xmit+0x53e/0x590 net/ipv4/ip_gre.c:650 __netdev_start_xmit include/linux/netdevice.h:4611 [inline] netdev_start_xmit include/linux/netdevice.h:4625 [inline] xmit_one+0xc0/0x310 net/core/dev.c:3556 dev_hard_start_xmit net/core/dev.c:3572 [inline] __dev_queue_xmit+0xf00/0x15a0 net/core/dev.c:4131 dev_queue_xmit+0x13/0x20 net/core/dev.c:4164 __bpf_tx_skb net/core/filter.c:2086 [inline] __bpf_redirect_no_mac net/core/filter.c:2111 [inline] __bpf_redirect+0x56a/0x7c0 net/core/filter.c:2134 ____bpf_clone_redirect net/core/filter.c:2165 [inline] bpf_clone_redirect+0x168/0x1c0 net/core/filter.c:2137 bpf_prog_3ff5f1ab1a2cda7e+0x5c/0xf74 bpf_dispatcher_nop_func include/linux/bpf.h:556 [inline] bpf_test_run+0x26d/0x4a0 net/bpf/test_run.c:49 bpf_prog_test_run_skb+0x463/0xb00 net/bpf/test_run.c:459 bpf_prog_test_run kernel/bpf/syscall.c:2983 [inline] __do_sys_bpf+0x3859/0x98a0 kernel/bpf/syscall.c:4135 __se_sys_bpf kernel/bpf/syscall.c:4075 [inline] __x64_sys_bpf+0x3d/0x50 kernel/bpf/syscall.c:4075 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8880b3748140 of 8 bytes by task 32518 on cpu 1: iptunnel_xmit_stats include/net/ip_tunnels.h:459 [inline] iptunnel_xmit+0x423/0x4b0 net/ipv4/ip_tunnel_core.c:86 ip_tunnel_xmit+0x1099/0x11c0 net/ipv4/ip_tunnel.c:816 __gre_xmit net/ipv4/ip_gre.c:466 [inline] ipgre_xmit+0x53e/0x590 net/ipv4/ip_gre.c:650 __netdev_start_xmit include/linux/netdevice.h:4611 [inline] netdev_start_xmit include/linux/netdevice.h:4625 [inline] xmit_one+0xc0/0x310 net/core/dev.c:3556 dev_hard_start_xmit net/core/dev.c:3572 [inline] __dev_queue_xmit+0xf00/0x15a0 net/core/dev.c:4131 dev_queue_xmit+0x13/0x20 net/core/dev.c:4164 __bpf_tx_skb net/core/filter.c:2086 [inline] __bpf_redirect_no_mac net/core/filter.c:2111 [inline] __bpf_redirect+0x56a/0x7c0 net/core/filter.c:2134 ____bpf_clone_redirect net/core/filter.c:2165 [inline] bpf_clone_redirect+0x168/0x1c0 net/core/filter.c:2137 bpf_prog_bebbfe2050753572+0x5c/0xebc bpf_dispatcher_nop_func include/linux/bpf.h:556 [inline] bpf_test_run+0x26d/0x4a0 net/bpf/test_run.c:49 bpf_prog_test_run_skb+0x463/0xb00 net/bpf/test_run.c:459 bpf_prog_test_run kernel/bpf/syscall.c:2983 [inline] __do_sys_bpf+0x3859/0x98a0 kernel/bpf/syscall.c:4135 __se_sys_bpf kernel/bpf/syscall.c:4075 [inline] __x64_sys_bpf+0x3d/0x50 kernel/bpf/syscall.c:4075 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 32518 Comm: syz-executor.0 Not tainted 5.8.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================