================================================================== BUG: KCSAN: data-race in tcp_send_challenge_ack / tcp_send_challenge_ack read to 0xffffffff8713bbb0 of 4 bytes by interrupt on cpu 1: tcp_send_challenge_ack+0x116/0x200 net/ipv4/tcp_input.c:3632 tcp_validate_incoming+0x7c9/0xdd0 net/ipv4/tcp_input.c:5778 tcp_rcv_state_process+0x33d/0x1010 net/ipv4/tcp_input.c:6507 tcp_v4_do_rcv+0x434/0x5a0 net/ipv4/tcp_ipv4.c:1684 tcp_v4_rcv+0x17c8/0x1a30 net/ipv4/tcp_ipv4.c:2078 ip_protocol_deliver_rcu+0x23f/0x490 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x126/0x160 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:307 [inline] ip_local_deliver+0x100/0x1b0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish net/ipv4/ip_input.c:444 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip_rcv+0x1b1/0x260 net/ipv4/ip_input.c:564 __netif_receive_skb_one_core net/core/dev.c:5485 [inline] __netif_receive_skb+0x8b/0x1b0 net/core/dev.c:5599 process_backlog+0x23f/0x3b0 net/core/dev.c:5927 __napi_poll+0x65/0x390 net/core/dev.c:6511 napi_poll net/core/dev.c:6578 [inline] net_rx_action+0x37e/0x730 net/core/dev.c:6689 __do_softirq+0x158/0x2e3 kernel/softirq.c:571 run_ksoftirqd+0x1f/0x30 kernel/softirq.c:934 smpboot_thread_fn+0x308/0x4a0 kernel/smpboot.c:164 kthread+0x1a9/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 write to 0xffffffff8713bbb0 of 4 bytes by task 30061 on cpu 0: tcp_send_challenge_ack+0x15c/0x200 net/ipv4/tcp_input.c:3636 tcp_validate_incoming+0x7c9/0xdd0 net/ipv4/tcp_input.c:5778 tcp_rcv_state_process+0x33d/0x1010 net/ipv4/tcp_input.c:6507 tcp_v4_do_rcv+0x434/0x5a0 net/ipv4/tcp_ipv4.c:1684 sk_backlog_rcv include/net/sock.h:1100 [inline] __release_sock+0xa7/0x220 net/core/sock.c:2852 release_sock+0x40/0x110 net/core/sock.c:3408 inet_wait_for_connect net/ipv4/af_inet.c:593 [inline] __inet_stream_connect+0x3e4/0x6d0 net/ipv4/af_inet.c:685 inet_stream_connect+0x44/0x70 net/ipv4/af_inet.c:724 __sys_connect_file net/socket.c:1976 [inline] __sys_connect+0x197/0x1b0 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __x64_sys_connect+0x3d/0x50 net/socket.c:2000 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x028f6873 -> 0x028f687a Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 30061 Comm: syz-executor.4 Not tainted 6.0.0-rc3-syzkaller-00007-gdcf8e5633e2e-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 ==================================================================