From: Peter Wu <pe...@lekensteyn.nl> Avoid possible connection drops on Linux (when tcp_syncookies is disabled) or fallbacks to SYN cookies with the following kernel warning:
TCP: request_sock_TCP: Possible SYN flooding on port 1234. Sending cookies. Check SNMP counters. Since Linux 4.4 (ef547f2ac16b "tcp: remove max_qlen_log"), a backlog of zero is really treated as the "queue length for completely established sockets waiting to be accepted" (listen(2)). This is apparently a valid interpretation of an "implementation-defined minimum value" for a backlog value of 0 (listen(3p)). Previous kernels would use 8 as minimum value, but that is no longer the case. Signed-off-by: Peter Wu <pe...@lekensteyn.nl> Signed-off-by: Michael Tokarev <m...@tls.msk.ru> --- gdbstub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/gdbstub.c b/gdbstub.c index b9e3710..ffcad0e 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -1629,7 +1629,7 @@ static int gdbserver_open(int port) close(fd); return -1; } - ret = listen(fd, 0); + ret = listen(fd, 1); if (ret < 0) { perror("listen"); close(fd); -- 2.1.4