Address user reported coverity issues.

programs/pkey/dh_client.c

@@ -125,6 +125,7 @@ int main( void )
         ( ret = mbedtls_mpi_read_file( &rsa.E, 16, f ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_mpi_read_file returned %d\n\n", ret );
+        fclose( f );
         goto exit;
     }
 

programs/pkey/dh_genprime.c

@@ -172,6 +172,7 @@ int main( int argc, char **argv )
         ( ret = mbedtls_mpi_write_file( "G = ", &G, 16, fout ) != 0 ) )
     {
         mbedtls_printf( " failed\n  ! mbedtls_mpi_write_file returned %d\n\n", ret );
+        fclose( fout );
         goto exit;
     }
 

programs/pkey/dh_server.c

@@ -132,6 +132,7 @@ int main( void )
         ( ret = mbedtls_mpi_read_file( &rsa.QP, 16, f ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_mpi_read_file returned %d\n\n", ret );
+        fclose( f );
         goto exit;
     }
 
@@ -157,6 +158,7 @@ int main( void )
         mbedtls_mpi_read_file( &dhm.G, 16, f ) != 0 )
     {
         mbedtls_printf( " failed\n  ! Invalid DH parameter file\n\n" );
+        fclose( f );
         goto exit;
     }
 

programs/pkey/pk_sign.c

@@ -142,6 +142,7 @@ int main( int argc, char *argv[] )
     if( fwrite( buf, 1, olen, f ) != olen )
     {
         mbedtls_printf( "failed\n  ! fwrite failed\n\n" );
+        fclose( f );
         goto exit;
     }
 

programs/pkey/rsa_decrypt.c

@@ -116,6 +116,7 @@ int main( int argc, char *argv[] )
         ( ret = mbedtls_mpi_read_file( &rsa.QP, 16, f ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_mpi_read_file returned %d\n\n", ret );
+        fclose( f );
         goto exit;
     }
 

programs/pkey/rsa_encrypt.c

@@ -110,6 +110,7 @@ int main( int argc, char *argv[] )
         ( ret = mbedtls_mpi_read_file( &rsa.E, 16, f ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_mpi_read_file returned %d\n\n", ret );
+        fclose( f );
         goto exit;
     }
 

programs/pkey/rsa_sign.c

@@ -98,6 +98,7 @@ int main( int argc, char *argv[] )
         ( ret = mbedtls_mpi_read_file( &rsa.QP, 16, f ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_mpi_read_file returned %d\n\n", ret );
+        fclose( f );
         goto exit;
     }
 

programs/pkey/rsa_sign_pss.c

@@ -153,6 +153,7 @@ int main( int argc, char *argv[] )
     if( fwrite( buf, 1, olen, f ) != olen )
     {
         mbedtls_printf( "failed\n  ! fwrite failed\n\n" );
+        fclose( f );
         goto exit;
     }
 

programs/pkey/rsa_verify.c

@@ -89,6 +89,7 @@ int main( int argc, char *argv[] )
         ( ret = mbedtls_mpi_read_file( &rsa.E, 16, f ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_mpi_read_file returned %d\n\n", ret );
+        fclose( f );
         goto exit;
     }