From 7dd220bcdb773f80bb5fdf268a9b675eafccebde Mon Sep 17 00:00:00 2001
From: "Dr. Tobias Quathamer" <toddy@debian.org>
Date: Sat, 19 Oct 2019 14:03:22 +0200
Subject: [PATCH] Fix CVE-2019-17596

Cherry-picked from upstream:
https://github.com/golang/go/commit/2017d88dbc096381d4f348d2fb08bfb3c2b7ed73

Gbp-Pq: Name 0008-Fix-CVE-2019-17596.patch
---
 src/crypto/dsa/dsa.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/crypto/dsa/dsa.go b/src/crypto/dsa/dsa.go
index 575314b..2fc4f1f 100644
--- a/src/crypto/dsa/dsa.go
+++ b/src/crypto/dsa/dsa.go
@@ -279,6 +279,9 @@ func Verify(pub *PublicKey, hash []byte, r, s *big.Int) bool {
 	}
 
 	w := new(big.Int).ModInverse(s, pub.Q)
+	if w == nil {
+		return false
+	}
 
 	n := pub.Q.BitLen()
 	if n&7 != 0 {
-- 
2.30.2