dns-domain: enforce maximum DNS domain name length

[elogind.git] / src / resolve / resolved-dns-domain.c

diff --git a/src/resolve/resolved-dns-domain.c b/src/resolve/resolved-dns-domain.c
index 33ae2610e117460c2a59ac4b313234448f942229..a41052dde39eee8407436ca0fe64f0df85339b3c 100644 (file)
--- a/src/resolve/resolved-dns-domain.c
+++ b/src/resolve/resolved-dns-domain.c
@@ -45,6 +45,9 @@ int dns_label_unescape(const char **name, char *dest, size_t sz) {
                 if (sz <= 0)
                         return -ENOSPC;
 
+                if (r >= DNS_LABEL_MAX)
+                        return -EINVAL;
+
                 if (*n == '\\') {
                         /* Escaped character */
 
@@ -114,6 +117,9 @@ int dns_label_escape(const char *p, size_t l, char **ret) {
         assert(p);
         assert(ret);
 
+        if (l > DNS_LABEL_MAX)
+                return -EINVAL;
+
         s = malloc(l * 4 + 1);
         if (!s)
                 return -ENOMEM;
@@ -197,6 +203,9 @@ int dns_name_normalize(const char *s, char **_ret) {
                 n += r;
         }
 
+        if (n > DNS_NAME_MAX)
+                return -EINVAL;
+
         if (!GREEDY_REALLOC(ret, allocated, n + 1))
                 return -ENOMEM;