net: fix /proc/net/igmp,igmp6 reading bug on linux

Fixes #2130.

R=rsc, dave
CC=golang-dev
https://golang.org/cl/4846044

diff --git a/src/pkg/net/interface_linux.go b/src/pkg/net/interface_linux.go
index 5af531dee6584378447ff0e2e43ccd6a357d8b1b..3d2a0bb9f8a0a614142e871bd9cd653fb3fbd730 100644 (file)
--- a/src/pkg/net/interface_linux.go
+++ b/src/pkg/net/interface_linux.go
@@ -190,10 +190,8 @@ func newAddr(attrs []syscall.NetlinkRouteAttr, family int) []Addr {
 // addresses for a specific interface.
 func interfaceMulticastAddrTable(ifindex int) ([]Addr, os.Error) {
        var (
-               ifi    *Interface
-               err    os.Error
-               ifmat4 []Addr
-               ifmat6 []Addr
+               ifi *Interface
+               err os.Error
        )
 
        if ifindex > 0 {
@@ -203,20 +201,13 @@ func interfaceMulticastAddrTable(ifindex int) ([]Addr, os.Error) {
                }
        }
 
-       ifmat4, err = parseProcNetIGMP(ifi)
-       if err != nil {
-               return nil, err
-       }
-
-       ifmat6, err = parseProcNetIGMP6(ifi)
-       if err != nil {
-               return nil, err
-       }
+       ifmat4 := parseProcNetIGMP(ifi)
+       ifmat6 := parseProcNetIGMP6(ifi)
 
        return append(ifmat4, ifmat6...), nil
 }
 
-func parseProcNetIGMP(ifi *Interface) ([]Addr, os.Error) {
+func parseProcNetIGMP(ifi *Interface) []Addr {
        var (
                ifmat []Addr
                name  string
@@ -224,7 +215,7 @@ func parseProcNetIGMP(ifi *Interface) ([]Addr, os.Error) {
 
        fd, err := open("/proc/net/igmp")
        if err != nil {
-               return nil, err
+               return nil
        }
        defer fd.close()
 
@@ -244,15 +235,15 @@ func parseProcNetIGMP(ifi *Interface) ([]Addr, os.Error) {
                }
        }
 
-       return ifmat, nil
+       return ifmat
 }
 
-func parseProcNetIGMP6(ifi *Interface) ([]Addr, os.Error) {
+func parseProcNetIGMP6(ifi *Interface) []Addr {
        var ifmat []Addr
 
        fd, err := open("/proc/net/igmp6")
        if err != nil {
-               return nil, err
+               return nil
        }
        defer fd.close()
 
@@ -267,5 +258,5 @@ func parseProcNetIGMP6(ifi *Interface) ([]Addr, os.Error) {
                }
        }
 
-       return ifmat, nil
+       return ifmat
 }