Ensure that we have enough buffer for gethostname and terminate it correctly.dhcpcd-4.0.8

2 files changed, 8 insertions, 6 deletions

diff --git a/dhcpcd.c b/dhcpcd.c
index 93d8b8d6..58321ef7 100644
--- a/dhcpcd.c
+++ b/dhcpcd.c
@@ -648,7 +648,9 @@ main(int argc, char **argv)
 	}
 #endif
 
-	gethostname(options->hostname + 1, sizeof(options->hostname));
+	gethostname(options->hostname + 1, HOSTNAME_MAX_LEN);
+	/* Ensure that the hostname is NULL terminated */ 
+	options->hostname[HOSTNAME_MAX_LEN + 1] = '\0';
 	if (strcmp(options->hostname + 1, "(none)") == 0 ||
 	    strcmp(options->hostname + 1, "localhost") == 0)
 		options->hostname[1] = '\0';
diff --git a/dhcpcd.h b/dhcpcd.h
index 1cd2b5d5..0aeffaed 100644
--- a/dhcpcd.h
+++ b/dhcpcd.h
@@ -82,12 +82,12 @@ struct options {
 	char script[PATH_MAX];
 	char pidfile[PATH_MAX];
 
-	char hostname[HOSTNAME_MAX_LEN + 1];
+	char hostname[HOSTNAME_MAX_LEN + 2];
 	int fqdn;
-	uint8_t vendorclassid[VENDORCLASSID_MAX_LEN + 1];
-	char clientid[CLIENTID_MAX_LEN + 1];
-	uint8_t userclass[USERCLASS_MAX_LEN + 1];
-	uint8_t vendor[VENDOR_MAX_LEN + 1];
+	uint8_t vendorclassid[VENDORCLASSID_MAX_LEN + 2];
+	char clientid[CLIENTID_MAX_LEN + 2];
+	uint8_t userclass[USERCLASS_MAX_LEN + 2];
+	uint8_t vendor[VENDOR_MAX_LEN + 2];
 
 	size_t blacklist_len;
 	in_addr_t *blacklist;