Merge pull request #17521 from poettering/resolved-more-fixes

six fixes to resolved

man/udev_device_get_syspath.xml

@@ -173,7 +173,7 @@
       <citerefentry><refentrytitle>udev_enumerate_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
       <citerefentry><refentrytitle>udev_monitor_new_from_netlink</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
       <citerefentry><refentrytitle>udev_list_entry</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
-      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
     </para>
   </refsect1>
 

src/resolve/resolved-dns-answer.c

@@ -11,6 +11,9 @@
 DnsAnswer *dns_answer_new(size_t n) {
         DnsAnswer *a;
 
+        if (n > UINT16_MAX) /* We can only place 64K RRs in an answer at max */
+                n = UINT16_MAX;
+
         a = malloc0(offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * n);
         if (!a)
                 return NULL;
@@ -624,12 +627,16 @@ int dns_answer_reserve(DnsAnswer **a, size_t n_free) {
                         return -EBUSY;
 
                 ns = (*a)->n_rrs + n_free;
+                if (ns > UINT16_MAX) /* Maximum number of RRs we can stick into a DNS packet section */
+                        ns = UINT16_MAX;
 
                 if ((*a)->n_allocated >= ns)
                         return 0;
 
                 /* Allocate more than we need */
                 ns *= 2;
+                if (ns > UINT16_MAX)
+                        ns = UINT16_MAX;
 
                 n = realloc(*a, offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * ns);
                 if (!n)
@@ -706,7 +713,7 @@ void dns_answer_dump(DnsAnswer *answer, FILE *f) {
                         fputs("\t;", f);
 
                 if (ifindex != 0)
-                        printf(" ifindex=%i", ifindex);
+                        fprintf(f, " ifindex=%i", ifindex);
                 if (flags & DNS_ANSWER_AUTHENTICATED)
                         fputs(" authenticated", f);
                 if (flags & DNS_ANSWER_CACHEABLE)

src/resolve/resolved-dns-dnssec.c

@@ -1813,6 +1813,8 @@ int dnssec_nsec_test(DnsAnswer *answer, DnsResourceKey *key, DnssecNsecResult *r
 
                 /* The following checks only make sense for NSEC RRs that are not expanded from a wildcard */
                 r = dns_resource_record_is_synthetic(rr);
+                if (r == -ENODATA) /* No signing RR known. */
+                        continue;
                 if (r < 0)
                         return r;
                 if (r > 0)

src/resolve/resolved-dns-question.c

@@ -8,7 +8,8 @@
 DnsQuestion *dns_question_new(size_t n) {
         DnsQuestion *q;
 
-        assert(n > 0);
+        if (n > UINT16_MAX) /* We can only place 64K key in an question section at max */
+                n = UINT16_MAX;
 
         q = malloc0(offsetof(DnsQuestion, keys) + sizeof(DnsResourceKey*) * n);
         if (!q)

src/resolve/resolved-dns-rr.c

@@ -1650,7 +1650,7 @@ DnsResourceRecord *dns_resource_record_copy(DnsResourceRecord *rr) {
                         return NULL;
                 copy->nsec3.salt_size = rr->nsec3.salt_size;
                 copy->nsec3.next_hashed_name = memdup(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size);
-                if (!copy->nsec3.next_hashed_name_size)
+                if (!copy->nsec3.next_hashed_name)
                         return NULL;
                 copy->nsec3.next_hashed_name_size = rr->nsec3.next_hashed_name_size;
                 copy->nsec3.types = bitmap_copy(rr->nsec3.types);

src/resolve/resolved-dns-scope.c

@@ -1156,12 +1156,16 @@ bool dns_scope_name_wants_search_domain(DnsScope *s, const char *name) {
 bool dns_scope_network_good(DnsScope *s) {
         /* Checks whether the network is in good state for lookups on this scope. For mDNS/LLMNR/Classic DNS scopes
          * bound to links this is easy, as they don't even exist if the link isn't in a suitable state. For the global
-         * DNS scope we check whether there are any links that are up and have an address. */
+         * DNS scope we check whether there are any links that are up and have an address.
+         *
+         * Note that Linux routing is complex and even systems that superficially have no IPv4 address might
+         * be able to route IPv4 (and similar for IPv6), hence let's make a check here independent of address
+         * family. */
 
         if (s->link)
                 return true;
 
-        return manager_routable(s->manager, AF_UNSPEC);
+        return manager_routable(s->manager);
 }
 
 int dns_scope_ifindex(DnsScope *s) {

src/resolve/resolved-manager.c

@@ -1418,15 +1418,15 @@ void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResource
         m->n_dnssec_verdict[verdict]++;
 }
 
-bool manager_routable(Manager *m, int family) {
+bool manager_routable(Manager *m) {
         Link *l;
 
         assert(m);
 
-        /* Returns true if the host has at least one interface with a routable address of the specified type */
+        /* Returns true if the host has at least one interface with a routable address (regardless if IPv4 or IPv6) */
 
         HASHMAP_FOREACH(l, m->links)
-                if (link_relevant(l, family, false))
+                if (link_relevant(l, AF_UNSPEC, false))
                         return true;
 
         return false;

src/resolve/resolved-manager.h

@@ -185,7 +185,7 @@ DnsOverTlsMode manager_get_dns_over_tls_mode(Manager *m);
 
 void manager_dnssec_verdict(Manager *m, DnssecVerdict verdict, const DnsResourceKey *key);
 
-bool manager_routable(Manager *m, int family);
+bool manager_routable(Manager *m);
 
 void manager_flush_caches(Manager *m);
 void manager_reset_server_features(Manager *m);