From 6c0be857f8fee7807a2a704465d2e0f6b1f021e3 Mon Sep 17 00:00:00 2001
From: Russell O'Connor <roconnor@blockstream.io>
Date: Wed, 12 May 2021 10:06:52 -0400
Subject: [PATCH] Verify that secp256k1_ge_set_gej_zinv does not operate on
 infinity. a->x and a->y should not be used if the infinity flag is set.

---
 src/group_impl.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/group_impl.h b/src/group_impl.h
index 6fc58ea01599a..bce9fbdad5642 100644
--- a/src/group_impl.h
+++ b/src/group_impl.h
@@ -67,6 +67,7 @@ static const secp256k1_fe secp256k1_fe_const_b = SECP256K1_FE_CONST(0, 0, 0, 0,
 static void secp256k1_ge_set_gej_zinv(secp256k1_ge *r, const secp256k1_gej *a, const secp256k1_fe *zi) {
     secp256k1_fe zi2;
     secp256k1_fe zi3;
+    VERIFY_CHECK(!a->infinity);
     secp256k1_fe_sqr(&zi2, zi);
     secp256k1_fe_mul(&zi3, &zi2, zi);
     secp256k1_fe_mul(&r->x, &a->x, &zi2);