Merge release-20210112.0-77-g76da673a0 (automated)
diff --git a/pkg/tcpip/network/ipv4/igmp.go b/pkg/tcpip/network/ipv4/igmp.go
index 9515fde..4550aac 100644
--- a/pkg/tcpip/network/ipv4/igmp.go
+++ b/pkg/tcpip/network/ipv4/igmp.go
@@ -157,14 +157,13 @@
}
h := header.IGMP(headerView)
- // Temporarily reset the checksum field to 0 in order to calculate the proper
- // checksum.
- wantChecksum := h.Checksum()
- h.SetChecksum(0)
- gotChecksum := ^header.ChecksumVV(pkt.Data, 0 /* initial */)
- h.SetChecksum(wantChecksum)
-
- if gotChecksum != wantChecksum {
+ // As per RFC 1071 section 1.3,
+ //
+ // To check a checksum, the 1's complement sum is computed over the
+ // same set of octets, including the checksum field. If the result
+ // is all 1 bits (-0 in 1's complement arithmetic), the check
+ // succeeds.
+ if header.ChecksumVV(pkt.Data, 0 /* initial */) != 0xFFFF {
received.checksumErrors.Increment()
return
}
