From: Andrew Gerrand <adg@golang.org>
Date: Wed, 13 Nov 2013 03:29:35 +0000 (+1100)
Subject: [release-branch.go1.2] net/textproto: fix CanonicalMIMEHeaderKey panic
X-Git-Tag: go1.2rc4~17
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=4f8794d3e7079c826d979c55300a3d4036e512f8;p=gostls13.git

[release-branch.go1.2] net/textproto: fix CanonicalMIMEHeaderKey panic

««« CL 21450043 / e081962da65c
net/textproto: fix CanonicalMIMEHeaderKey panic

Fixes #6712

R=golang-dev, adg, rsc
CC=golang-dev
https://golang.org/cl/21450043
»»»

R=golang-dev
CC=golang-dev
https://golang.org/cl/25640044
---

diff --git a/src/pkg/net/textproto/reader.go b/src/pkg/net/textproto/reader.go
index 56ece5b087..b0c07413c1 100644
--- a/src/pkg/net/textproto/reader.go
+++ b/src/pkg/net/textproto/reader.go
@@ -574,13 +574,10 @@ func canonicalMIMEHeaderKey(a []byte) string {
 		// and upper case after each dash.
 		// (Host, User-Agent, If-Modified-Since).
 		// MIME headers are ASCII only, so no Unicode issues.
-		if a[i] == ' ' {
-			a[i] = '-'
-			upper = true
-			continue
-		}
 		c := a[i]
-		if upper && 'a' <= c && c <= 'z' {
+		if c == ' ' {
+			c = '-'
+		} else if upper && 'a' <= c && c <= 'z' {
 			c -= toLower
 		} else if !upper && 'A' <= c && c <= 'Z' {
 			c += toLower
diff --git a/src/pkg/net/textproto/reader_test.go b/src/pkg/net/textproto/reader_test.go
index f27042d4e9..cc12912b63 100644
--- a/src/pkg/net/textproto/reader_test.go
+++ b/src/pkg/net/textproto/reader_test.go
@@ -25,6 +25,10 @@ var canonicalHeaderKeyTests = []canonicalHeaderKeyTest{
 	{"user-agent", "User-Agent"},
 	{"USER-AGENT", "User-Agent"},
 	{"üser-agenT", "üser-Agent"}, // non-ASCII unchanged
+
+	// This caused a panic due to mishandling of a space:
+	{"C Ontent-Transfer-Encoding", "C-Ontent-Transfer-Encoding"},
+	{"foo bar", "Foo-Bar"},
 }
 
 func TestCanonicalMIMEHeaderKey(t *testing.T) {