Fix some Coverity-detected issues.

Author: michaelrsweet

CHANGES.md

@@ -11,6 +11,7 @@ libcups v3.0.0 (YYYY-MM-DD)
 - Fixed a potential timing issue with `cupsEnumDests`.
 - Fixed a bug in the Avahi implementation of `cupsDNSSDBrowseNew`.
 - Fixed a memory leak in `httpClose`.
+- Fixed some Coverity-detected issues.
 
 
 libcups v3.0rc4 (2025-03-18)

cups/dnssd.c

@@ -3009,20 +3009,19 @@ avahi_resolve_cb(
 
   DEBUG_printf("3avahi_resolve_cb(resolver=%p, if_index=%d, protocol=%d, event=%s, name=\"%s\", type=\"%s\", domain=\"%s\", host=\"%s\", address=%p, port=%u, txtrec=%p, flags=%u, resolve=%p)", (void *)resolver, if_index, protocol, avahi_events[event], name, type, domain, host, (void *)address, (unsigned)port, (void *)txtrec, (unsigned)flags, (void *)resolve);
 
-  if (!resolver || event != AVAHI_RESOLVER_FOUND)
+  if (!resolver)
     return;
 
-  (void)resolver;
   (void)protocol;
   (void)flags;
 
   // Map the addresses "127.0.0.1" (IPv4) and "::1" (IPv6) to "localhost" to work around a well-known Avahi registration bug for local-only services (Issue #970)
-  if (address->proto == AVAHI_PROTO_INET && address->data.ipv4.address == htonl(0x7f000001))
+  if (address && address->proto == AVAHI_PROTO_INET && address->data.ipv4.address == htonl(0x7f000001))
   {
     DEBUG_puts("4avahi_resolve_cb: Mapping 127.0.0.1 to localhost.");
     host = "localhost";
   }
-  else if (address->proto == AVAHI_PROTO_INET6 && address->data.ipv6.address[0] == 0 && address->data.ipv6.address[1] == 0 && address->data.ipv6.address[2] == 0 && address->data.ipv6.address[3] == 0 && address->data.ipv6.address[4] == 0 && address->data.ipv6.address[5] == 0 && address->data.ipv6.address[6] == 0 && address->data.ipv6.address[7] == 0 && address->data.ipv6.address[8] == 0 && address->data.ipv6.address[9] == 0 && address->data.ipv6.address[10] == 0 && address->data.ipv6.address[11] == 0 && address->data.ipv6.address[12] == 0 && address->data.ipv6.address[13] == 0 && address->data.ipv6.address[14] == 0 && address->data.ipv6.address[15] == 1)
+  else if (address && address->proto == AVAHI_PROTO_INET6 && address->data.ipv6.address[0] == 0 && address->data.ipv6.address[1] == 0 && address->data.ipv6.address[2] == 0 && address->data.ipv6.address[3] == 0 && address->data.ipv6.address[4] == 0 && address->data.ipv6.address[5] == 0 && address->data.ipv6.address[6] == 0 && address->data.ipv6.address[7] == 0 && address->data.ipv6.address[8] == 0 && address->data.ipv6.address[9] == 0 && address->data.ipv6.address[10] == 0 && address->data.ipv6.address[11] == 0 && address->data.ipv6.address[12] == 0 && address->data.ipv6.address[13] == 0 && address->data.ipv6.address[14] == 0 && address->data.ipv6.address[15] == 1)
   {
     DEBUG_puts("4avahi_resolve_cb: Mapping ::1 to localhost.");
     host = "localhost";

cups/http.c

@@ -1562,6 +1562,7 @@ httpPeek(http_t *http,			// I - HTTP connection
     {
       DEBUG_puts("2httpPeek: Unable to copy decompressor stream.");
       http->error = ENOMEM;
+      inflateEnd(&stream);
       return (-1);
     }
 

cups/tls-gnutls.c

@@ -1740,8 +1740,12 @@ _httpTLSStart(http_t *http)		// I - Connection to server
 		*cnptr;			// Pointer into common name
     bool	have_creds = false;	// Have credentials?
 
+    cupsMutexLock(&tls_mutex);
+
     if (!tls_common_name)
     {
+      cupsMutexUnlock(&tls_mutex);
+
       if (http->fields[HTTP_FIELD_HOST])
       {
 	// Use hostname for TLS upgrade...
@@ -1775,9 +1779,9 @@ _httpTLSStart(http_t *http)		// I - Connection to server
 
       if (hostname[0])
 	cn = hostname;
-    }
 
-    cupsMutexLock(&tls_mutex);
+      cupsMutexLock(&tls_mutex);
+    }
 
     if (!cn)
       cn = tls_common_name;

cups/tls-openssl.c

@@ -1797,9 +1797,13 @@ _httpTLSStart(http_t *http)		// I - Connection to server
 
     context = SSL_CTX_new(TLS_server_method());
 
+    // Find the TLS certificate...
+    cupsMutexLock(&tls_mutex);
+
     if (!tls_common_name)
     {
-      // Find the TLS certificate...
+      cupsMutexUnlock(&tls_mutex);
+
       if (http->fields[HTTP_FIELD_HOST])
       {
 	// Use hostname for TLS upgrade...
@@ -1836,9 +1840,9 @@ _httpTLSStart(http_t *http)		// I - Connection to server
 
       if (hostname[0])
 	cn = hostname;
-    }
 
-    cupsMutexLock(&tls_mutex);
+      cupsMutexLock(&tls_mutex);
+    }
 
     if (!cn)
       cn = tls_common_name;