From: Jason A. Donenfeld <Jason@zx2c4.com>
Date: Sat, 21 Oct 2023 17:32:07 +0000 (+0200)
Subject: conn: set unused OOB to zero length
X-Git-Tag: 0.0.20250515~21
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b3df23dcd40ba4568572f338f9fd16b87053fc29;p=thirdparty%2Fwireguard-go.git

conn: set unused OOB to zero length

Otherwise in the event that we're using GSO without sticky sockets, we
pass garbage OOB buffers to sendmmsg, making a EINVAL, when GSO doesn't
set its header.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---

diff --git a/conn/bind_std.go b/conn/bind_std.go
index e1bcbd1..46df7fd 100644
--- a/conn/bind_std.go
+++ b/conn/bind_std.go
@@ -65,7 +65,7 @@ func NewStdNetBind() Bind {
 				msgs := make([]ipv6.Message, IdealBatchSize)
 				for i := range msgs {
 					msgs[i].Buffers = make(net.Buffers, 1)
-					msgs[i].OOB = make([]byte, stickyControlSize+gsoControlSize)
+					msgs[i].OOB = make([]byte, 0, stickyControlSize+gsoControlSize)
 				}
 				return &msgs
 			},
@@ -200,6 +200,7 @@ again:
 
 func (s *StdNetBind) putMessages(msgs *[]ipv6.Message) {
 	for i := range *msgs {
+		(*msgs)[i].OOB = (*msgs)[i].OOB[:0]
 		(*msgs)[i] = ipv6.Message{Buffers: (*msgs)[i].Buffers, OOB: (*msgs)[i].OOB}
 	}
 	s.msgsPool.Put(msgs)