commit 9721b868a29d4306d2f63a67e71e84596e7721e0
author Gilles Peskine <Gilles.Peskine@arm.com> Mon Feb 26 11:41:22 2024 +0100
committer Gilles Peskine <Gilles.Peskine@arm.com> Mon Feb 26 12:38:16 2024 +0100
tree 9c7a093ea51626b9ad2e80b0524947ef60bcdf86
parent 84dc44b9b53239123480ba7314764b7aa4895fda

Allow null buffers when the length is 0

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>

library/ecp.c

diff --git a/library/ecp.c b/library/ecp.c
index c98eb7b..cfe02b0 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -927,7 +927,7 @@
     size_t plen;
     ECP_VALIDATE_RET(grp != NULL);
     ECP_VALIDATE_RET(pt  != NULL);
-    ECP_VALIDATE_RET(buf != NULL);
+    ECP_VALIDATE_RET(ilen == 0 || buf != NULL);
 
     if (ilen < 1) {
         return MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
@@ -996,7 +996,7 @@
     ECP_VALIDATE_RET(grp != NULL);
     ECP_VALIDATE_RET(pt  != NULL);
     ECP_VALIDATE_RET(buf != NULL);
-    ECP_VALIDATE_RET(*buf != NULL);
+    ECP_VALIDATE_RET(buf_len == 0 || *buf != NULL);
 
     /*
      * We must have at least two bytes (1 for length, at least one for data)
@@ -1068,7 +1068,7 @@
     mbedtls_ecp_group_id grp_id;
     ECP_VALIDATE_RET(grp  != NULL);
     ECP_VALIDATE_RET(buf  != NULL);
-    ECP_VALIDATE_RET(*buf != NULL);
+    ECP_VALIDATE_RET(len == 0 || *buf != NULL);
 
     if ((ret = mbedtls_ecp_tls_read_group_id(&grp_id, buf, len)) != 0) {
         return ret;
@@ -1088,7 +1088,7 @@
     const mbedtls_ecp_curve_info *curve_info;
     ECP_VALIDATE_RET(grp  != NULL);
     ECP_VALIDATE_RET(buf  != NULL);
-    ECP_VALIDATE_RET(*buf != NULL);
+    ECP_VALIDATE_RET(len == 0 || *buf != NULL);
 
     /*
      * We expect at least three bytes (see below)
@@ -3361,7 +3361,7 @@
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
     ECP_VALIDATE_RET(key != NULL);
-    ECP_VALIDATE_RET(buf != NULL);
+    ECP_VALIDATE_RET(buflen == 0 || buf != NULL);
 
 #if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
     if (mbedtls_ecp_get_type(&key->grp) == MBEDTLS_ECP_TYPE_MONTGOMERY) {