X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=crypto%2Fbn%2Fbn_gf2m.c;h=b2222a06c93f868ce8b1da6f90e170c59cf997af;hb=7b3e11c54466f1da8b707c932e308d345fd61101;hp=2cd93ddc76cf3bdadccd5640606fa5ceb6f82ba0;hpb=0a06ad76a11d0952230a2a1f60c4112ff25255ce;p=oweals%2Fopenssl.git

diff --git a/crypto/bn/bn_gf2m.c b/crypto/bn/bn_gf2m.c
index 2cd93ddc76..b2222a06c9 100644
--- a/crypto/bn/bn_gf2m.c
+++ b/crypto/bn/bn_gf2m.c
@@ -525,7 +525,7 @@ err:
  */
 int BN_GF2m_mod_inv(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
 	{
-	BIGNUM *b, *c, *u, *v, *tmp;
+	BIGNUM *b, *c = NULL, *u = NULL, *v = NULL, *tmp;
 	int ret = 0;
 
 	bn_check_top(a);
@@ -631,8 +631,11 @@ int BN_GF2m_mod_inv(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
 			}
 		if (ubits==vbits)
 			{
-			bn_correct_top(u);
-			ubits = BN_num_bits(u);
+			BN_ULONG ul;
+			int utop = (ubits-1)/BN_BITS2;
+
+			while ((ul=udp[utop])==0 && utop) utop--;
+			ubits = utop*BN_BITS2 + BN_num_bits_word(ul);
 			}
 		}
 	bn_correct_top(b);
@@ -646,6 +649,8 @@ int BN_GF2m_mod_inv(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx)
 err:
 #ifdef BN_DEBUG /* BN_CTX_end would complain about the expanded form */
         bn_correct_top(c);
+        bn_correct_top(u);
+        bn_correct_top(v);
 #endif
   	BN_CTX_end(ctx);
 	return ret;