refresh dns_labels struct, instead of reallocating it

which cuts down on the leaks while fuzzing, but doesn't eliminate
them.

diff --git a/src/protocols/dns/decode.c b/src/protocols/dns/decode.c
index b6e1340eafe23a290c7bd8aa3709f45deab9c851..6b3b6c923b7c05f0e42586e872538a1c45eb9698 100644 (file)
--- a/src/protocols/dns/decode.c
+++ b/src/protocols/dns/decode.c
@@ -580,8 +580,21 @@ static ssize_t fr_dns_decode_proto(TALLOC_CTX *ctx, fr_pair_list_t *list, uint8_
        packet_ctx->packet = data;
        packet_ctx->packet_len = data_len;
 
-       packet_ctx->lb = fr_dns_labels_init(packet_ctx, data, 256);
-       fr_assert(packet_ctx->lb != NULL);
+       if (packet_ctx->lb) {
+               fr_dns_labels_t *lb = packet_ctx->lb;
+
+               lb->start = data;
+
+               /*
+                *      Always skip the DNS packet header.
+                */
+               lb->blocks[0].start = 12;
+               lb->blocks[0].end = 12;
+               lb->num = 1;
+       } else {
+               packet_ctx->lb = fr_dns_labels_init(packet_ctx, data, 256);
+               fr_assert(packet_ctx->lb != NULL);
+       }
 
        return fr_dns_decode(ctx, data, data_len, &cursor, packet_ctx);
 }