commit 1ffc5cb4a5cf709f612bb7c858cfd2e183142d27
author Thomas Daubney <thomas.daubney@arm.com> Wed Jan 31 18:09:36 2024 +0000
committer Thomas Daubney <thomas.daubney@arm.com> Mon Feb 12 12:07:38 2024 +0000
tree 50d5f43e8c9377cb094cf8d6c44e3e5cad77a6e8
parent 7480a74cba8528faee4b4e31e68106746b7c2b03

Modify allocation and buffer wiping in sign_finish

Allocate immediately after declaration and only wipe
tag buffer if allocation didn't fail.

Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>

library/psa_crypto.c

diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 356137d..a9456fd 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -2693,6 +2693,7 @@
     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
     psa_status_t abort_status = PSA_ERROR_CORRUPTION_DETECTED;
     LOCAL_OUTPUT_DECLARE(mac_external, mac);
+    LOCAL_OUTPUT_ALLOC(mac_external, mac_size, mac);
 
     if (operation->id == 0) {
         status = PSA_ERROR_BAD_STATE;
@@ -2716,7 +2717,7 @@
         goto exit;
     }
 
-    LOCAL_OUTPUT_ALLOC(mac_external, mac_size, mac);
+
     status = psa_driver_wrapper_mac_sign_finish(operation,
                                                 mac, operation->mac_size,
                                                 mac_length);
@@ -2733,7 +2734,9 @@
         operation->mac_size = 0;
     }
 
-    psa_wipe_tag_output_buffer(mac, status, mac_size, *mac_length);
+    if (status != PSA_ERROR_INSUFFICIENT_MEMORY) {
+        psa_wipe_tag_output_buffer(mac, status, mac_size, *mac_length);
+    }
 
     abort_status = psa_mac_abort(operation);
     LOCAL_OUTPUT_FREE(mac_external, mac);