SIG: reject records with a zero length signature

(cherry picked from commit 9b93e5d68485469b704052c2997764891df7bff7)

diff --git a/lib/dns/rdata/generic/sig_24.c b/lib/dns/rdata/generic/sig_24.c
index a2cf1cee68dc9b7572573b722c713b40f8dcc251..8fbc97f72ee6f5777a43bd1c3f25463a63ba846b 100644 (file)
--- a/lib/dns/rdata/generic/sig_24.c
+++ b/lib/dns/rdata/generic/sig_24.c
@@ -266,6 +266,9 @@ fromwire_sig(ARGS_FROMWIRE) {
         * Sig.
         */
        isc_buffer_activeregion(source, &sr);
+       if (sr.length == 0) {
+               return (ISC_R_UNEXPECTEDEND);
+       }
        isc_buffer_forward(source, sr.length);
        return (mem_tobuffer(target, sr.base, sr.length));
 }