diff --git a/tests/suites/test_suite_psa_crypto.data b/tests/suites/test_suite_psa_crypto.data
index d9dd9ef48..83ce15873 100644
--- a/tests/suites/test_suite_psa_crypto.data
+++ b/tests/suites/test_suite_psa_crypto.data
@@ -1012,31 +1012,127 @@ cipher_verify_output:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4
 
 PSA symmetric encryption multipart: AES-CBC-nopad, 7+9 bytes
 depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
-cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":7:"a076ec9dfbe47d52afc357336f20743b"
+cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":7:0:16:"a076ec9dfbe47d52afc357336f20743b"
 
 PSA symmetric encryption multipart: AES-CBC-nopad, 3+13 bytes
 depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
-cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":3:"a076ec9dfbe47d52afc357336f20743b"
+cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":3:0:16:"a076ec9dfbe47d52afc357336f20743b"
 
 PSA symmetric encryption multipart: AES-CBC-nopad, 4+12 bytes
 depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
-cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":4:"a076ec9dfbe47d52afc357336f20743b"
+cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":4:0:16:"a076ec9dfbe47d52afc357336f20743b"
 
 PSA symmetric encryption multipart: AES-CBC-nopad, 11+5 bytes
 depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
-cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":11:"a076ec9dfbe47d52afc357336f20743b"
+cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":11:0:16:"a076ec9dfbe47d52afc357336f20743b"
+
+PSA symmetric encryption multipart: AES-CBC-nopad, 16+16 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
+cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":16:16:16:"a076ec9dfbe47d52afc357336f20743b89906f2f9207ac02aa658cb4ef19c61f"
+
+PSA symmetric encryption multipart: AES-CBC-nopad, 12+20 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
+cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":12:0:32:"a076ec9dfbe47d52afc357336f20743b89906f2f9207ac02aa658cb4ef19c61f"
+
+PSA symmetric encryption multipart: AES-CBC-nopad, 20+12 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
+cipher_encrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":20:16:16:"a076ec9dfbe47d52afc357336f20743b89906f2f9207ac02aa658cb4ef19c61f"
+
+PSA symmetric encryption multipart: AES-CTR, 11+5 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":11:11:5:"8f9408fe80a81d3e813da3c7b0b2bd32"
+
+PSA symmetric encryption multipart: AES-CTR, 16+16 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":16:16:16:"8f9408fe80a81d3e813da3c7b0b2bd321c965bb1de7baf71025f6ef6393ca587"
+
+PSA symmetric encryption multipart: AES-CTR, 12+20 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":12:12:20:"8f9408fe80a81d3e813da3c7b0b2bd321c965bb1de7baf71025f6ef6393ca587"
+
+PSA symmetric encryption multipart: AES-CTR, 20+12 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":20:20:12:"8f9408fe80a81d3e813da3c7b0b2bd321c965bb1de7baf71025f6ef6393ca587"
+
+PSA symmetric encryption multipart: AES-CTR, 12+10 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597":12:12:10:"8f9408fe80a81d3e813da3c7b0b2bd321c965bb1de7b"
+
+PSA symmetric encryption multipart: AES-CTR, 0+15 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e11739317":0:0:15:"8f9408fe80a81d3e813da3c7b0b2bd"
+
+PSA symmetric encryption multipart: AES-CTR, 15+0 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e11739317":15:15:0:"8f9408fe80a81d3e813da3c7b0b2bd"
+
+PSA symmetric encryption multipart: AES-CTR, 0+16 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":0:0:16:"8f9408fe80a81d3e813da3c7b0b2bd32"
+
+PSA symmetric encryption multipart: AES-CTR, 16+0 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_encrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":16:16:0:"8f9408fe80a81d3e813da3c7b0b2bd32"
 
 PSA symmetric decryption multipart: AES-CBC-nopad, 7+9 bytes
 depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
-cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b":7:"6bc1bee22e409f96e93d7e117393172a"
+cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b":7:0:16:"6bc1bee22e409f96e93d7e117393172a"
 
 PSA symmetric decryption multipart: AES-CBC-nopad, 3+13 bytes
 depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
-cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b":3:"6bc1bee22e409f96e93d7e117393172a"
+cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b":3:0:16:"6bc1bee22e409f96e93d7e117393172a"
 
 PSA symmetric decryption multipart: AES-CBC-nopad, 11+5 bytes
 depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
-cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b":11:"6bc1bee22e409f96e93d7e117393172a"
+cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b":11:0:16:"6bc1bee22e409f96e93d7e117393172a"
+
+PSA symmetric decryption multipart: AES-CBC-nopad, 16+16 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
+cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b89906f2f9207ac02aa658cb4ef19c61f":16:16:16:"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef"
+
+PSA symmetric decryption multipart: AES-CBC-nopad, 12+20 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
+cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b89906f2f9207ac02aa658cb4ef19c61f":12:0:32:"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef"
+
+PSA symmetric decryption multipart: AES-CBC-nopad, 20+12 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
+cipher_decrypt_multipart:PSA_ALG_CBC_NO_PADDING:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"a076ec9dfbe47d52afc357336f20743b89906f2f9207ac02aa658cb4ef19c61f":20:16:16:"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef"
+
+PSA symmetric encryption multipart: AES-CTR, 11+5 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":11:11:5:"8f9408fe80a81d3e813da3c7b0b2bd32"
+
+PSA symmetric encryption multipart: AES-CTR, 16+16 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":16:16:16:"8f9408fe80a81d3e813da3c7b0b2bd321c965bb1de7baf71025f6ef6393ca587"
+
+PSA symmetric encryption multipart: AES-CTR, 12+20 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":12:12:20:"8f9408fe80a81d3e813da3c7b0b2bd321c965bb1de7baf71025f6ef6393ca587"
+
+PSA symmetric encryption multipart: AES-CTR, 20+12 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597bcef1389318c7fc865ef":20:20:12:"8f9408fe80a81d3e813da3c7b0b2bd321c965bb1de7baf71025f6ef6393ca587"
+
+PSA symmetric encryption multipart: AES-CTR, 12+10 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a5434f378a597":12:12:10:"8f9408fe80a81d3e813da3c7b0b2bd321c965bb1de7b"
+
+PSA symmetric decryption multipart: AES-CTR, 0+15 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e11739317":0:0:15:"8f9408fe80a81d3e813da3c7b0b2bd"
+
+PSA symmetric decryption multipart: AES-CTR, 15+0 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e11739317":15:15:0:"8f9408fe80a81d3e813da3c7b0b2bd"
+
+PSA symmetric decryption multipart: AES-CTR, 0+16 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":0:0:16:"8f9408fe80a81d3e813da3c7b0b2bd32"
+
+PSA symmetric decryption multipart: AES-CTR, 16+0 bytes
+depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
+cipher_decrypt_multipart:PSA_ALG_CTR:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":"6bc1bee22e409f96e93d7e117393172a":16:16:0:"8f9408fe80a81d3e813da3c7b0b2bd32"
 
 PSA symmetric encrypt/decrypt multipart: AES-CBC-nopad, 11+5 bytes
 depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC
diff --git a/tests/suites/test_suite_psa_crypto.function b/tests/suites/test_suite_psa_crypto.function
index cccc87033..d900f4d79 100644
--- a/tests/suites/test_suite_psa_crypto.function
+++ b/tests/suites/test_suite_psa_crypto.function
@@ -2415,8 +2415,8 @@ void cipher_encrypt( int alg_arg, int key_type_arg,
                                    &function_output_length ) );
     total_output_length += function_output_length;
     status = psa_cipher_finish( &operation,
-                                output + function_output_length,
-                                output_buffer_size,
+                                output + total_output_length,
+                                output_buffer_size - total_output_length,
                                 &function_output_length );
     total_output_length += function_output_length;
 
@@ -2439,12 +2439,16 @@ exit:
 void cipher_encrypt_multipart( int alg_arg, int key_type_arg,
                                data_t *key,
                                data_t *input,
-                               int first_part_size,
+                               int first_part_size_arg,
+                               int output1_length_arg, int output2_length_arg,
                                data_t *expected_output )
 {
     psa_key_handle_t handle = 0;
     psa_key_type_t key_type = key_type_arg;
     psa_algorithm_t alg = alg_arg;
+    size_t first_part_size = first_part_size_arg;
+    size_t output1_length = output1_length_arg;
+    size_t output2_length = output2_length_arg;
     unsigned char iv[16] = {0};
     size_t iv_size;
     unsigned char *output = NULL;
@@ -2475,20 +2479,23 @@ void cipher_encrypt_multipart( int alg_arg, int key_type_arg,
                            PSA_BLOCK_CIPHER_BLOCK_SIZE( key_type ) );
     ASSERT_ALLOC( output, output_buffer_size );
 
-    TEST_ASSERT( (unsigned int) first_part_size < input->len );
+    TEST_ASSERT( first_part_size <= input->len );
     PSA_ASSERT( psa_cipher_update( &operation, input->x, first_part_size,
                                    output, output_buffer_size,
                                    &function_output_length ) );
+    TEST_ASSERT( function_output_length == output1_length );
     total_output_length += function_output_length;
     PSA_ASSERT( psa_cipher_update( &operation,
                                    input->x + first_part_size,
                                    input->len - first_part_size,
-                                   output, output_buffer_size,
+                                   output + total_output_length,
+                                   output_buffer_size - total_output_length,
                                    &function_output_length ) );
+    TEST_ASSERT( function_output_length == output2_length );
     total_output_length += function_output_length;
     PSA_ASSERT( psa_cipher_finish( &operation,
-                                   output + function_output_length,
-                                   output_buffer_size,
+                                   output + total_output_length,
+                                   output_buffer_size - total_output_length,
                                    &function_output_length ) );
     total_output_length += function_output_length;
     PSA_ASSERT( psa_cipher_abort( &operation ) );
@@ -2507,13 +2514,17 @@ exit:
 void cipher_decrypt_multipart( int alg_arg, int key_type_arg,
                                data_t *key,
                                data_t *input,
-                               int first_part_size,
+                               int first_part_size_arg,
+                               int output1_length_arg, int output2_length_arg,
                                data_t *expected_output )
 {
     psa_key_handle_t handle = 0;
 
     psa_key_type_t key_type = key_type_arg;
     psa_algorithm_t alg = alg_arg;
+    size_t first_part_size = first_part_size_arg;
+    size_t output1_length = output1_length_arg;
+    size_t output2_length = output2_length_arg;
     unsigned char iv[16] = {0};
     size_t iv_size;
     unsigned char *output = NULL;
@@ -2545,21 +2556,24 @@ void cipher_decrypt_multipart( int alg_arg, int key_type_arg,
                            PSA_BLOCK_CIPHER_BLOCK_SIZE( key_type ) );
     ASSERT_ALLOC( output, output_buffer_size );
 
-    TEST_ASSERT( (unsigned int) first_part_size < input->len );
+    TEST_ASSERT( first_part_size <= input->len );
     PSA_ASSERT( psa_cipher_update( &operation,
                                    input->x, first_part_size,
                                    output, output_buffer_size,
                                    &function_output_length ) );
+    TEST_ASSERT( function_output_length == output1_length );
     total_output_length += function_output_length;
     PSA_ASSERT( psa_cipher_update( &operation,
                                    input->x + first_part_size,
                                    input->len - first_part_size,
-                                   output, output_buffer_size,
+                                   output + total_output_length,
+                                   output_buffer_size - total_output_length,
                                    &function_output_length ) );
+    TEST_ASSERT( function_output_length == output2_length );
     total_output_length += function_output_length;
     PSA_ASSERT( psa_cipher_finish( &operation,
-                                   output + function_output_length,
-                                   output_buffer_size,
+                                   output + total_output_length,
+                                   output_buffer_size - total_output_length,
                                    &function_output_length ) );
     total_output_length += function_output_length;
     PSA_ASSERT( psa_cipher_abort( &operation ) );
@@ -2622,8 +2636,8 @@ void cipher_decrypt( int alg_arg, int key_type_arg,
                                    &function_output_length ) );
     total_output_length += function_output_length;
     status = psa_cipher_finish( &operation,
-                                output + function_output_length,
-                                output_buffer_size,
+                                output + total_output_length,
+                                output_buffer_size - total_output_length,
                                 &function_output_length );
     total_output_length += function_output_length;
     TEST_EQUAL( status, expected_status );
@@ -2689,7 +2703,8 @@ void cipher_verify_output( int alg_arg, int key_type_arg,
                                    output1, output1_size,
                                    &output1_length ) );
     PSA_ASSERT( psa_cipher_finish( &operation1,
-                                   output1 + output1_length, output1_size,
+                                   output1 + output1_length,
+                                   output1_size - output1_length,
                                    &function_output_length ) );
 
     output1_length += function_output_length;
@@ -2707,7 +2722,7 @@ void cipher_verify_output( int alg_arg, int key_type_arg,
     function_output_length = 0;
     PSA_ASSERT( psa_cipher_finish( &operation2,
                                    output2 + output2_length,
-                                   output2_size,
+                                   output2_size - output2_length,
                                    &function_output_length ) );
 
     output2_length += function_output_length;
@@ -2729,11 +2744,12 @@ void cipher_verify_output_multipart( int alg_arg,
                                      int key_type_arg,
                                      data_t *key,
                                      data_t *input,
-                                     int first_part_size )
+                                     int first_part_size_arg )
 {
     psa_key_handle_t handle = 0;
     psa_key_type_t key_type = key_type_arg;
     psa_algorithm_t alg = alg_arg;
+    size_t first_part_size = first_part_size_arg;
     unsigned char iv[16] = {0};
     size_t iv_size = 16;
     size_t iv_length = 0;
@@ -2769,7 +2785,7 @@ void cipher_verify_output_multipart( int alg_arg,
                             PSA_BLOCK_CIPHER_BLOCK_SIZE( key_type ) );
     ASSERT_ALLOC( output1, output1_buffer_size );
 
-    TEST_ASSERT( (unsigned int) first_part_size < input->len );
+    TEST_ASSERT( first_part_size <= input->len );
 
     PSA_ASSERT( psa_cipher_update( &operation1, input->x, first_part_size,
                                    output1, output1_buffer_size,