$OpenBSD: patch-sockets_c,v 1.1 2020/04/22 20:07:47 jasper Exp $

Fix incorrect use of fprintf()
https://sources.debian.org/patches/x2vnc/1.7.2-6/format-security.patch/

Index: sockets.c
--- sockets.c.orig
+++ sockets.c
@@ -48,7 +48,7 @@ ReadExact(int sock, char *buf, int n)
 	j = read(sock, buf + i, (n - i));
 	if (j <= 0) {
 	    if (j < 0) {
-		fprintf(stderr,programName);
+		fprintf(stderr,"%s",programName);
 		perror(": read");
 	    } else {
 		if (errorMessageFromReadExact) {
@@ -79,7 +79,7 @@ WriteExact(int sock, char *buf, int n)
 	j = write(sock, buf + i, (n - i));
 	if (j <= 0) {
 	    if (j < 0) {
-		fprintf(stderr,programName);
+		fprintf(stderr,"%s",programName);
 		perror(": write");
 	    } else {
 		fprintf(stderr,"%s: write failed\n",programName);
@@ -109,13 +109,13 @@ ConnectToTcpAddr(unsigned int host, int port)
 
     sock = socket(AF_INET, SOCK_STREAM, 0);
     if (sock < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": ConnectToTcpAddr: socket");
 	return -1;
     }
 
     if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": ConnectToTcpAddr: connect");
 	close(sock);
 	return -1;
@@ -123,7 +123,7 @@ ConnectToTcpAddr(unsigned int host, int port)
 
     if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
 		   (char *)&one, sizeof(one)) < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": ConnectToTcpAddr: setsockopt");
 	close(sock);
 	return -1;
@@ -151,28 +151,28 @@ ListenAtTcpPort(int port)
 
     sock = socket(AF_INET, SOCK_STREAM, 0);
     if (sock < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": ListenAtTcpPort: socket");
 	return -1;
     }
 
     if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
 		   (const char *)&one, sizeof(one)) < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": ListenAtTcpPort: setsockopt");
 	close(sock);
 	return -1;
     }
 
     if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": ListenAtTcpPort: bind");
 	close(sock);
 	return -1;
     }
 
     if (listen(sock, 5) < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": ListenAtTcpPort: listen");
 	close(sock);
 	return -1;
@@ -196,14 +196,14 @@ AcceptTcpConnection(int listenSock)
 
     sock = accept(listenSock, (struct sockaddr *) &addr, &addrlen);
     if (sock < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": AcceptTcpConnection: accept");
 	return -1;
     }
 
     if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
 		   (char *)&one, sizeof(one)) < 0) {
-	fprintf(stderr,programName);
+	fprintf(stderr,"%s",programName);
 	perror(": AcceptTcpConnection: setsockopt");
 	close(sock);
 	return -1;
