Commit cc1fef63 authored by Andy Polyakov's avatar Andy Polyakov
Browse files

bn/bn_lib.c: remove bn_check_top from bn_expand2. 



Trouble is that addition is postponing expansion till carry is
calculated, and if addition carries, top word can be zero, which
triggers assertion in bn_check_top.

Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
Reviewed-by: default avatarDavid Benjamin <davidben@google.com>
(Merged from https://github.com/openssl/openssl/pull/6662)

(cherry picked from commit e42395e6)
parent dcb83330

crypto/bn/bn_lib.c

+0 −5
Original line number Diff line number Diff line
@@ -222,8 +222,6 @@ static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) 
    const BN_ULONG *B;

    int i;



    bn_check_top(b);



    if (words > (INT_MAX / (4 * BN_BITS2))) {

        BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_BIGNUM_TOO_LONG);

        return NULL;
@@ -298,8 +296,6 @@ static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) 


BIGNUM *bn_expand2(BIGNUM *b, int words)

{

    bn_check_top(b);



    if (words > b->dmax) {

        BN_ULONG *a = bn_expand_internal(b, words);

        if (!a)
@@ -312,7 +308,6 @@ BIGNUM *bn_expand2(BIGNUM *b, int words) 
        b->dmax = words;

    }



    bn_check_top(b);

    return b;

}