From: Remi Tricot-Le Breton <rlebreton@haproxy.com>
Date: Tue, 28 Oct 2025 17:00:42 +0000 (+0100)
Subject: BUG/MINOR: init: Do not close previously created fd in stdio_quiet
X-Git-Tag: v3.3-dev11~21
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c606ff45a0cab8f08a0b06df17737ec309cf4170;p=thirdparty%2Fhaproxy.git

BUG/MINOR: init: Do not close previously created fd in stdio_quiet

During init we were calling 'stdio_quiet' and passing the previously
created 'devnullfd' file descriptor. But the 'stdio_quiet' was also
closed afterwards which raised an error (EBADF).
If we keep from closing FDs that were opened outside of the
'stdio_quiet' function we will let the caller manage its FD and avoid
double close calls.

This patch can be backported to all stable branches.
---

diff --git a/src/haproxy.c b/src/haproxy.c
index 8127f0e04..1a43ae6e0 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -893,8 +893,11 @@ static void dump(struct sig_handler *sh)
  */
 void stdio_quiet(int fd)
 {
-	if (fd < 0)
+	int close_fd = 0;
+	if (fd < 0) {
 		fd = open("/dev/null", O_RDWR, 0);
+		close_fd = 1;
+	}
 
 	if (fd > -1) {
 		fclose(stdin);
@@ -904,7 +907,7 @@ void stdio_quiet(int fd)
 		dup2(fd, 0);
 		dup2(fd, 1);
 		dup2(fd, 2);
-		if (fd > 2)
+		if (fd > 2 && close_fd)
 			close(fd);
 		return;
 	}