From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Tue, 17 Aug 2021 07:32:40 +0000 (+0200)
Subject: dnsdist: Avoid arithmetic on bitfields, as suggested by Otto
X-Git-Tag: dnsdist-1.7.0-alpha1~63^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=refs%2Fpull%2F10650%2Fhead;p=thirdparty%2Fpdns.git

dnsdist: Avoid arithmetic on bitfields, as suggested by Otto
---

diff --git a/pdns/dnsdist.cc b/pdns/dnsdist.cc
index 8f3e34b114..900e2facdb 100644
--- a/pdns/dnsdist.cc
+++ b/pdns/dnsdist.cc
@@ -294,7 +294,7 @@ static void restoreFlags(struct dnsheader* dh, uint16_t origFlags)
 
 static uint16_t getRDAndCDFlagsFromDNSHeader(const struct dnsheader* dh)
 {
-  return static_cast<uint16_t>((dh->rd << FLAGS_RD_OFFSET) + (dh->cd << FLAGS_CD_OFFSET));
+  return static_cast<uint16_t>(dh->rd) << FLAGS_RD_OFFSET | static_cast<uint16_t>(dh->cd) << FLAGS_CD_OFFSET;
 }
 
 static bool fixUpQueryTurnedResponse(DNSQuestion& dq, const uint16_t origFlags)