net: return "cannot unmarshal" error while parsing DNS messages

Change-Id: I407f5d3d3a3e8b3d43ff154f731d885e831971e9
GitHub-Last-Rev: d6a400d1ba6a09e726c9b4e4774a7e8a611611e8
GitHub-Pull-Request: golang/go#62155
Reviewed-on: https://go-review.googlesource.com/c/go/+/520980
Run-TryBot: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Mateusz Poliwczak <mpoliwczak34@gmail.com>

diff --git a/src/net/dnsclient_unix.go b/src/net/dnsclient_unix.go
index ed32ba028069ca63352eb3fbe838cf49b5639732..f9d5d183189f9793e323cd800db4a1a9c30c985e 100644 (file)
--- a/src/net/dnsclient_unix.go
+++ b/src/net/dnsclient_unix.go
@@ -718,7 +718,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
                                h, err := result.p.AnswerHeader()
                                if err != nil && err != dnsmessage.ErrSectionDone {
                                        lastErr = &DNSError{
-                                               Err:    "cannot marshal DNS message",
+                                               Err:    errCannotUnmarshalDNSMessage.Error(),
                                                Name:   name,
                                                Server: result.server,
                                        }
@@ -731,7 +731,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
                                        a, err := result.p.AResource()
                                        if err != nil {
                                                lastErr = &DNSError{
-                                                       Err:    "cannot marshal DNS message",
+                                                       Err:    errCannotUnmarshalDNSMessage.Error(),
                                                        Name:   name,
                                                        Server: result.server,
                                                }
@@ -746,7 +746,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
                                        aaaa, err := result.p.AAAAResource()
                                        if err != nil {
                                                lastErr = &DNSError{
-                                                       Err:    "cannot marshal DNS message",
+                                                       Err:    errCannotUnmarshalDNSMessage.Error(),
                                                        Name:   name,
                                                        Server: result.server,
                                                }
@@ -761,7 +761,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
                                        c, err := result.p.CNAMEResource()
                                        if err != nil {
                                                lastErr = &DNSError{
-                                                       Err:    "cannot marshal DNS message",
+                                                       Err:    errCannotUnmarshalDNSMessage.Error(),
                                                        Name:   name,
                                                        Server: result.server,
                                                }
@@ -774,7 +774,7 @@ func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name strin
                                default:
                                        if err := result.p.SkipAnswer(); err != nil {
                                                lastErr = &DNSError{
-                                                       Err:    "cannot marshal DNS message",
+                                                       Err:    errCannotUnmarshalDNSMessage.Error(),
                                                        Name:   name,
                                                        Server: result.server,
                                                }
@@ -866,7 +866,7 @@ func (r *Resolver) goLookupPTR(ctx context.Context, addr string, order hostLooku
                }
                if err != nil {
                        return nil, &DNSError{
-                               Err:    "cannot marshal DNS message",
+                               Err:    errCannotUnmarshalDNSMessage.Error(),
                                Name:   addr,
                                Server: server,
                        }
@@ -875,7 +875,7 @@ func (r *Resolver) goLookupPTR(ctx context.Context, addr string, order hostLooku
                        err := p.SkipAnswer()
                        if err != nil {
                                return nil, &DNSError{
-                                       Err:    "cannot marshal DNS message",
+                                       Err:    errCannotUnmarshalDNSMessage.Error(),
                                        Name:   addr,
                                        Server: server,
                                }
@@ -885,7 +885,7 @@ func (r *Resolver) goLookupPTR(ctx context.Context, addr string, order hostLooku
                ptr, err := p.PTRResource()
                if err != nil {
                        return nil, &DNSError{
-                               Err:    "cannot marshal DNS message",
+                               Err:    errCannotUnmarshalDNSMessage.Error(),
                                Name:   addr,
                                Server: server,
                        }