1 files changed, 18 insertions, 17 deletions

diff --git a/src/lib/libcrypto/ec/ec_mult.c b/src/lib/libcrypto/ec/ec_mult.c
index e336cf0fac..8ef655690e 100644
--- a/src/lib/libcrypto/ec/ec_mult.c
+++ b/src/lib/libcrypto/ec/ec_mult.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ec_mult.c,v 1.36 2024/11/21 14:36:03 tb Exp $ */
+/* $OpenBSD: ec_mult.c,v 1.37 2024/11/21 15:03:56 tb Exp $ */
 /*
  * Originally written by Bodo Moeller and Nils Larsch for the OpenSSL project.
  */
@@ -371,27 +371,28 @@ ec_wNAF_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *m,
                         goto err;
 
                 for (i = 0; i < totalnum; i++) {
-                        if (wNAF_len[i] > (size_t) k) {
-                                int digit = wNAF[i][k];
-                                int is_neg;
+                        int digit;
+                        int is_neg = 0;
 
-                                if (digit) {
-                                        is_neg = digit < 0;
+                        if (k >= wNAF_len[i])
+                                continue;
 
-                                        if (is_neg)
-                                                digit = -digit;
+                        if ((digit = wNAF[i][k]) == 0)
+                                continue;
 
-                                        if (is_neg != r_is_inverted) {
-                                                if (!EC_POINT_invert(group, r, ctx))
-                                                        goto err;
-                                                r_is_inverted = !r_is_inverted;
-                                        }
-                                        /* digit > 0 */
+                        if (digit < 0) {
+                                is_neg = 1;
+                                digit = 0 - digit;
+                        }
 
-                                        if (!EC_POINT_add(group, r, r, val_sub[i][digit >> 1], ctx))
-                                                goto err;
-                                }
+                        if (is_neg != r_is_inverted) {
+                                if (!EC_POINT_invert(group, r, ctx))
+                                        goto err;
+                                r_is_inverted = !r_is_inverted;
                         }
+
+                        if (!EC_POINT_add(group, r, r, val_sub[i][digit >> 1], ctx))
+                                goto err;
                 }
         }