From c237de058f91072b5d54ad9c570049c14df6957e Mon Sep 17 00:00:00 2001 From: =?utf8?q?Bodo=20M=C3=B6ller?= Date: Tue, 27 Aug 2002 13:32:35 +0000 Subject: [PATCH] don't write beyond buffer Submitted by: Nils Larsch --- crypto/bn/bn_gf2m.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/crypto/bn/bn_gf2m.c b/crypto/bn/bn_gf2m.c index 8bd17e0e7c..dea1fd3b87 100644 --- a/crypto/bn/bn_gf2m.c +++ b/crypto/bn/bn_gf2m.c @@ -370,12 +370,16 @@ int BN_GF2m_mod_arr(BIGNUM *r, const BIGNUM *a, const unsigned int p[]) for (k = 1; p[k] > 0; k++) { + BN_ULONG tmp_ulong; + /* reducing component t^p[k]*/ n = p[k] / BN_BITS2; d0 = p[k] % BN_BITS2; d1 = BN_BITS2 - d0; z[n] ^= (zz << d0); - if (d0) z[n+1] ^= (zz >> d1); + tmp_ulong = zz >> d1; + if (d0 && tmp_ulong) + z[n+1] ^= tmp_ulong; } -- 2.34.1