From: Fazlul Shahriar <fshahriar@gmail.com>
Date: Mon, 29 Jun 2020 05:50:50 +0000 (-0400)
Subject: net: handle more interface types without a hardware address on Plan 9
X-Git-Tag: go1.15rc1~52
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=a980e8a690f59542e6e68aa4d84face19ee57a15;p=gostls13.git

net: handle more interface types without a hardware address on Plan 9

We were handling loopback devices when attempting to read hardware
address, but packet interfaces were not being handled. As a general fix,
don't attempt to read hardware address of any device that's not inside
/net.

Fixes #39908

Change-Id: Ifa05e270357e111c60906110db2cc23dc7c1c49c
Reviewed-on: https://go-review.googlesource.com/c/go/+/240259
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David du Colombier <0intro@gmail.com>
---

diff --git a/src/net/interface_plan9.go b/src/net/interface_plan9.go
index 1295017a1b..31bbaca467 100644
--- a/src/net/interface_plan9.go
+++ b/src/net/interface_plan9.go
@@ -68,8 +68,8 @@ func readInterface(i int) (*Interface, error) {
 	}
 	ifc.MTU = mtu
 
-	// Not a loopback device
-	if device != "/dev/null" {
+	// Not a loopback device ("/dev/null") or packet interface (e.g. "pkt2")
+	if stringsHasPrefix(device, netdir+"/") {
 		deviceaddrf, err := open(device + "/addr")
 		if err != nil {
 			return nil, err