From 6a1cc25494056e6b8dff243f8b3d9c57259535f6 Mon Sep 17 00:00:00 2001 From: Vitaly Chikunov Date: Thu, 21 Apr 2022 20:25:10 +0300 Subject: [PATCH] crypto: ecrdsa - Fix incorrect use of vli_cmp commit 7cc7ab73f83ee6d50dc9536bc3355495d8600fad upstream. Correctly compare values that shall be greater-or-equal and not just greater. Fixes: 0d7a78643f69 ("crypto: ecrdsa - add EC-RDSA (GOST 34.10) algorithm") Cc: Signed-off-by: Vitaly Chikunov Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/ecrdsa.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/crypto/ecrdsa.c b/crypto/ecrdsa.c index 6a3fd09057d0..f7ed43020672 100644 --- a/crypto/ecrdsa.c +++ b/crypto/ecrdsa.c @@ -113,15 +113,15 @@ static int ecrdsa_verify(struct akcipher_request *req) /* Step 1: verify that 0 < r < q, 0 < s < q */ if (vli_is_zero(r, ndigits) || - vli_cmp(r, ctx->curve->n, ndigits) == 1 || + vli_cmp(r, ctx->curve->n, ndigits) >= 0 || vli_is_zero(s, ndigits) || - vli_cmp(s, ctx->curve->n, ndigits) == 1) + vli_cmp(s, ctx->curve->n, ndigits) >= 0) return -EKEYREJECTED; /* Step 2: calculate hash (h) of the message (passed as input) */ /* Step 3: calculate e = h \mod q */ vli_from_le64(e, digest, ndigits); - if (vli_cmp(e, ctx->curve->n, ndigits) == 1) + if (vli_cmp(e, ctx->curve->n, ndigits) >= 0) vli_sub(e, e, ctx->curve->n, ndigits); if (vli_is_zero(e, ndigits)) e[0] = 1; @@ -137,7 +137,7 @@ static int ecrdsa_verify(struct akcipher_request *req) /* Step 6: calculate point C = z_1P + z_2Q, and R = x_c \mod q */ ecc_point_mult_shamir(&cc, z1, &ctx->curve->g, z2, &ctx->pub_key, ctx->curve); - if (vli_cmp(cc.x, ctx->curve->n, ndigits) == 1) + if (vli_cmp(cc.x, ctx->curve->n, ndigits) >= 0) vli_sub(cc.x, cc.x, ctx->curve->n, ndigits); /* Step 7: if R == r signature is valid */