From: Willy Tarreau <w@1wt.eu>
Date: Mon, 29 Aug 2022 14:48:14 +0000 (+0200)
Subject: MINOR: raw-sock: don't try to send if an error was already reported
X-Git-Tag: v2.7-dev5~41
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c6fc77404e70d62e8b425568c55dc971cbd516d7;p=thirdparty%2Fhaproxy.git

MINOR: raw-sock: don't try to send if an error was already reported

There's no point trying to send() on a socket on which an error was already
reported. This wastes syscalls. Till now it was possible to occasionally
see an attempt to sendto() after epoll_wait() had reported EPOLLERR.
---

diff --git a/src/raw_sock.c b/src/raw_sock.c
index b161f90f24..e172b1d4e5 100644
--- a/src/raw_sock.c
+++ b/src/raw_sock.c
@@ -360,6 +360,13 @@ static size_t raw_sock_from_buf(struct connection *conn, void *xprt_ctx, const s
 	if (!fd_send_ready(conn->handle.fd))
 		return 0;
 
+	if (unlikely(fdtab[conn->handle.fd].state & FD_POLL_ERR)) {
+		/* an error was reported on the FD, we can't send anymore */
+		conn->flags |= CO_FL_ERROR | CO_FL_SOCK_WR_SH | CO_FL_SOCK_RD_SH;
+		errno = EPIPE;
+		return 0;
+	}
+
 	if (conn->flags & CO_FL_SOCK_WR_SH) {
 		/* it's already closed */
 		conn->flags |= CO_FL_ERROR | CO_FL_SOCK_RD_SH;