src/crl.c: fix "null pointer passed as argument 2" in new XMEMCPY() call in WC_RSA_PSS path of DupCRL_Entry(), added in b140f93, detected by gcc 14.0.0_pre20240107 p15 with sanitizers.

Author: douzzer

src/crl.c

@@ -778,7 +778,9 @@ static CRL_Entry* DupCRL_Entry(const CRL_Entry* ent, void* heap)
         XMEMCPY(dupl->toBeSigned, ent->toBeSigned, dupl->tbsSz);
         XMEMCPY(dupl->signature, ent->signature, dupl->signatureSz);
     #ifdef WC_RSA_PSS
-        XMEMCPY(dupl->sigParams, ent->sigParams, dupl->sigParamsSz);
+        if (dupl->sigParamsSz > 0) {
+            XMEMCPY(dupl->sigParams, ent->sigParams, dupl->sigParamsSz);
+        }
     #endif
     }
     else {