From 4861f83686af25d1c898d06b140d3019a6c28461 Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Tue, 18 Nov 2014 12:36:20 +0100
Subject: [PATCH] Test whether recovered public keys are not infinity

Fixes a bug discovered by Sergio Demian Lerner.
---
 src/ecdsa_impl.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/ecdsa_impl.h b/src/ecdsa_impl.h
index 57e9978efa..4c05ec39f8 100644
--- a/src/ecdsa_impl.h
+++ b/src/ecdsa_impl.h
@@ -128,7 +128,7 @@ static int secp256k1_ecdsa_sig_recover(const secp256k1_ecdsa_sig_t *sig, secp256
     secp256k1_num_free(&rn);
     secp256k1_num_free(&u1);
     secp256k1_num_free(&u2);
-    return 1;
+    return !secp256k1_gej_is_infinity(&qj);
 }
 
 static int secp256k1_ecdsa_sig_verify(const secp256k1_ecdsa_sig_t *sig, const secp256k1_ge_t *pubkey, const secp256k1_num_t *message) {