From 64cfebc63c52bd54a98dd1c567544c16f012b1b2 Mon Sep 17 00:00:00 2001
From: Jakob Borg <jakob@nym.se>
Date: Thu, 10 Mar 2016 10:47:15 +0100
Subject: [PATCH] Branch names are hard

---
 build.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/build.go b/build.go
index 976060de3..fab0efcec 100644
--- a/build.go
+++ b/build.go
@@ -537,12 +537,18 @@ func getBranchSuffix() string {
 		return ""
 	}
 
-	branch = string(parts[len(parts)-1])
+	branch = parts[len(parts)-1]
 	if branch == "master" {
 		// master builds are the default.
 		return ""
 	}
 
+	validBranchRe := regexp.MustCompile(`^[a-zA-Z0-9_.-]$`)
+	if !validBranchRe.MatchString(branch) {
+		// There's some odd stuff in the branch name. Better skip it.
+		return ""
+	}
+
 	return "-" + branch
 }