Fix undocumented free() in x509_string_to_names()
Now programs/x509/cert_write san="DN:CN=#0000;DN:CN=#0000" is no longer
crashing with use-after-free, instead it's now failing cleanly:
failed
! mbedtls_x509_string_to_names returned -0x2800 - X509 - Input invalid
That's better of course but still not great, will be fixed by future
commits.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/library/x509_create.c b/library/x509_create.c
index 839b5df..420e36b 100644
--- a/library/x509_create.c
+++ b/library/x509_create.c
@@ -292,8 +292,12 @@
unsigned char data[MBEDTLS_X509_MAX_DN_NAME_SIZE];
size_t data_len = 0;
- /* Clear existing chain if present */
- mbedtls_asn1_free_named_data_list(head);
+ /* Ensure the output parameter is not already populated.
+ * (If it were, overwriting it would likely cause a memory leak.)
+ */
+ if (*head != NULL) {
+ return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
+ }
while (c <= end) {
if (in_attr_type && *c == '=') {