commit 716447ff32ccfaeb1c1967f9a9421dc8e72de529
author Gabor Mezei <gabor.mezei@arm.com> Wed Mar 01 16:11:11 2023 +0100
committer Gabor Mezei <gabor.mezei@arm.com> Wed Mar 08 14:09:51 2023 +0100
tree ede47037aea3203de03d3693ebdb32a8b79cfcf3
parent ed1acf642c2c11110cdc38124beaafbe4978fbcb

Fix limb size calculation

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>

library/ecp_curves.c

diff --git a/library/ecp_curves.c b/library/ecp_curves.c
index a4cd228..7d312ca 100644
--- a/library/ecp_curves.c
+++ b/library/ecp_curves.c
@@ -5108,7 +5108,7 @@
 static int ecp_mod_p256(mbedtls_mpi *N)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t expected_width = 2 * ((256 + biL - 1) / biL);
+    size_t expected_width = 2 * 256 / biL;
     MBEDTLS_MPI_CHK(mbedtls_mpi_grow(N, expected_width));
     ret = mbedtls_ecp_mod_p256_raw(N->p, expected_width);
 cleanup:
@@ -5118,7 +5118,7 @@
 MBEDTLS_STATIC_TESTABLE
 int mbedtls_ecp_mod_p256_raw(mbedtls_mpi_uint *X, size_t X_limbs)
 {
-    if (X_limbs != 2*((256 + biL - 1)/biL)) {
+    if (X_limbs != 2 * 256 / biL) {
         return MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
     }