From: Max Kellermann <max.kellermann@gmail.com>
Date: Thu, 21 Sep 2017 08:26:28 +0000 (+0200)
Subject: resolver: set the correct address size for local/abstract sockets
X-Git-Tag: v0.28~1
X-Git-Url: https://git.tokkee.org/?p=ncmpc.git;a=commitdiff_plain;h=f160a38904423ce6b97ecbf11203b6eefa890eb8

resolver: set the correct address size for local/abstract sockets

Limit the socklen_t to the real path length, and omit the trailing
null terminator in abstract sockets.
---

diff --git a/src/net/resolver.c b/src/net/resolver.c
index 952c2c9..2df1b5a 100644
--- a/src/net/resolver.c
+++ b/src/net/resolver.c
@@ -29,6 +29,7 @@
 #include "resolver.h"
 #include "config.h"
 
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -78,14 +79,17 @@ resolver_new(const char *host, unsigned port)
 
 	if (host[0] == '/' || host[0] == '@') {
 #ifndef WIN32
-		size_t path_length = strlen(host);
-		if (path_length >= sizeof(resolver->saun.sun_path)) {
+		const bool is_abstract = *host == '@';
+		/* sun_path must be null-terminated unless it's an abstract
+		   socket */
+		const size_t path_length = strlen(host) + !is_abstract;
+		if (path_length > sizeof(resolver->saun.sun_path)) {
 			free(resolver);
 			return NULL;
 		}
 
 		resolver->saun.sun_family = AF_UNIX;
-		memcpy(resolver->saun.sun_path, host, path_length + 1);
+		memcpy(resolver->saun.sun_path, host, path_length);
 
 		if (host[0] == '@')
 			/* abstract socket */
@@ -93,7 +97,8 @@ resolver_new(const char *host, unsigned port)
 
 		resolver->current.family = PF_UNIX;
 		resolver->current.protocol = 0;
-		resolver->current.addrlen = sizeof(resolver->saun);
+		resolver->current.addrlen = sizeof(resolver->saun)
+			- sizeof(resolver->saun.sun_path) + path_length;
 		resolver->current.addr = (const struct sockaddr *)&resolver->saun;
 		resolver->type = TYPE_ONE;
 #else /* WIN32 */