resolved: increase most label buffers to fit a trailing NUL byte

This is just paranoia. In all these cases we don't really care about the
trailing NUL byte. But if there's space for it dns_label_unescape() is
going to insert it, and that's a good safety strategy.

This is a follow-up to c29c3adefa8cd859f8cb87d9ad62f3d77b7cd102 which
fixed an actual bug, unlike this commit, which is just paranoia.

diff --git a/src/resolve/resolved-dns-dnssec.c b/src/resolve/resolved-dns-dnssec.c
index 2580c2333c366bc02c2037555a3ed25e779add23..3c9b90c89b229f6d62423859f13d8b983665d7ce 100644 (file)
--- a/src/resolve/resolved-dns-dnssec.c
+++ b/src/resolve/resolved-dns-dnssec.c
@@ -1951,7 +1951,7 @@ found_closest_encloser:
 }
 
 static int dnssec_nsec_wildcard_equal(DnsResourceRecord *rr, const char *name) {
-        char label[DNS_LABEL_MAX];
+        char label[DNS_LABEL_MAX+1];
         const char *n;
         int r;
 

diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index ca1eea4346309be1233ce76ee97b0f7866a35a28..991a1be458453766aa55fbfa10e914dc0d522a80 100644 (file)
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -552,7 +552,7 @@ int dns_packet_append_name(
 
         while (!dns_name_is_root(name)) {
                 const char *z = name;
-                char label[DNS_LABEL_MAX];
+                char label[DNS_LABEL_MAX+1];
                 size_t n = 0;
 
                 if (allow_compression)

diff --git a/src/resolve/resolved-manager.c b/src/resolve/resolved-manager.c
index b52619e287b433c490f9a2234ad1b45796a77449..0295662b5b5eae4f886adc940e4c7ce6acaa2f5a 100644 (file)
--- a/src/resolve/resolved-manager.c
+++ b/src/resolve/resolved-manager.c
@@ -388,7 +388,7 @@ static char* fallback_hostname(void) {
 
 static int make_fallback_hostnames(char **full_hostname, char **llmnr_hostname, char **mdns_hostname) {
         _cleanup_free_ char *h = NULL, *n = NULL, *m = NULL;
-        char label[DNS_LABEL_MAX];
+        char label[DNS_LABEL_MAX+1];
         const char *p;
         int r;
 

diff --git a/src/shared/dns-domain.c b/src/shared/dns-domain.c
index b41c9b06ca3bfa471eab87839b0bffc7435bab0c..909b4cdcc93aeedce4d5e43deedea64b26ad8c3b 100644 (file)
--- a/src/shared/dns-domain.c
+++ b/src/shared/dns-domain.c
@@ -410,7 +410,7 @@ int dns_name_concat(const char *a, const char *b, DNSLabelFlags flags, char **_r
                 goto finish;
 
         for (;;) {
-                char label[DNS_LABEL_MAX];
+                char label[DNS_LABEL_MAX+1];
 
                 r = dns_label_unescape(&p, label, sizeof label, flags);
                 if (r < 0)
@@ -507,7 +507,7 @@ int dns_name_compare_func(const char *a, const char *b) {
         y = b + strlen(b);
 
         for (;;) {
-                char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX];
+                char la[DNS_LABEL_MAX+1], lb[DNS_LABEL_MAX+1];
 
                 if (x == NULL && y == NULL)
                         return 0;
@@ -543,7 +543,7 @@ int dns_name_equal(const char *x, const char *y) {
         assert(y);
 
         for (;;) {
-                char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX];
+                char la[DNS_LABEL_MAX+1], lb[DNS_LABEL_MAX+1];
 
                 r = dns_label_unescape(&x, la, sizeof la, 0);
                 if (r < 0)
@@ -574,7 +574,7 @@ int dns_name_endswith(const char *name, const char *suffix) {
         s = suffix;
 
         for (;;) {
-                char ln[DNS_LABEL_MAX], ls[DNS_LABEL_MAX];
+                char ln[DNS_LABEL_MAX+1], ls[DNS_LABEL_MAX+1];
 
                 r = dns_label_unescape(&n, ln, sizeof ln, 0);
                 if (r < 0)
@@ -612,7 +612,7 @@ int dns_name_startswith(const char *name, const char *prefix) {
         p = prefix;
 
         for (;;) {
-                char ln[DNS_LABEL_MAX], lp[DNS_LABEL_MAX];
+                char ln[DNS_LABEL_MAX+1], lp[DNS_LABEL_MAX+1];
 
                 r = dns_label_unescape(&p, lp, sizeof lp, 0);
                 if (r < 0)
@@ -644,7 +644,7 @@ int dns_name_change_suffix(const char *name, const char *old_suffix, const char
         s = old_suffix;
 
         for (;;) {
-                char ln[DNS_LABEL_MAX], ls[DNS_LABEL_MAX];
+                char ln[DNS_LABEL_MAX+1], ls[DNS_LABEL_MAX+1];
 
                 if (!saved_before)
                         saved_before = n;
@@ -929,7 +929,7 @@ bool dns_srv_type_is_valid(const char *name) {
                 return false;
 
         for (;;) {
-                char label[DNS_LABEL_MAX];
+                char label[DNS_LABEL_MAX+1];
 
                 /* This more or less implements RFC 6335, Section 5.1 */
 
@@ -1227,7 +1227,7 @@ int dns_name_common_suffix(const char *a, const char *b, const char **ret) {
                 return m;
 
         for (;;) {
-                char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX];
+                char la[DNS_LABEL_MAX+1], lb[DNS_LABEL_MAX+1];
                 const char *x, *y;
 
                 if (k >= n || k >= m) {
@@ -1328,7 +1328,7 @@ int dns_name_apply_idna(const char *name, char **ret) {
         assert(ret);
 
         for (;;) {
-                char label[DNS_LABEL_MAX];
+                char label[DNS_LABEL_MAX+1];
 
                 r = dns_label_unescape(&name, label, sizeof label, 0);
                 if (r < 0)