VPP-635: CLI Memory leak with invalid parameter

In the CLI parsing, below is a common pattern:
  /* Get a line of input. */
  if (!unformat_user (input, unformat_line_input, line_input))
    return 0;

  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (line_input, "x"))
	x = 1;
      :
      else
	return clib_error_return (0, "unknown input `%U'",
				  format_unformat_error, line_input);
    }
  unformat_free (line_input);

The 'else' returns if an unknown string is encountered. There a memory
leak because the 'unformat_free(line_input)' is not called. There is a
large number of instances of this pattern.

Replaced the previous pattern with:
  /* Get a line of input. */
  if (!unformat_user (input, unformat_line_input, line_input))
    return 0;

  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (line_input, "x"))
	x = 1;
      :
      else
        {
	  error = clib_error_return (0, "unknown input `%U'",
				     format_unformat_error, line_input);
	  goto done:
        }
    }

  /* ...Remaining code... */

done:
  unformat_free (line_input);
  return error;
}

In multiple files, 'unformat_free (line_input);' was never called, so
there was a memory leak whether an invalid string was entered or not.

Also, there were multiple instance where:
	  error = clib_error_return (0, "unknown input `%U'",
				     format_unformat_error, line_input);
used 'input' as the last parameter instead of 'line_input'. The result
is that output did not contain the substring in error, instead just an
empty string. Fixed all of those as well.

There are a lot of file, and very mind numbing work, so tried to keep
it to a pattern to avoid mistakes.

Change-Id: I8902f0c32a47dd7fb3bb3471a89818571702f1d2
Signed-off-by: Billy McFall <bmcfall@redhat.com>
Signed-off-by: Dave Barach <dave@barachs.net>

1 files changed, 20 insertions, 6 deletions

diff --git a/src/vnet/l2/l2_patch.c b/src/vnet/l2/l2_patch.c
index 5e4691f45c7..ff3d2f3a6af 100644
--- a/src/vnet/l2/l2_patch.c
+++ b/src/vnet/l2/l2_patch.c
@@ -315,6 +315,7 @@ test_patch_command_fn (vlib_main_t * vm,
   int rx_set = 0;
   int tx_set = 0;
   int is_add = 1;
+  clib_error_t *error = NULL;
 
   /* Get a line of input. */
   if (!unformat_user (input, unformat_line_input, line_input))
@@ -335,10 +336,16 @@ test_patch_command_fn (vlib_main_t * vm,
     }
 
   if (rx_set == 0)
-    return clib_error_return (0, "rx interface not set");
+    {
+      error = clib_error_return (0, "rx interface not set");
+      goto done;
+    }
 
   if (tx_set == 0)
-    return clib_error_return (0, "tx interface not set");
+    {
+      error = clib_error_return (0, "tx interface not set");
+      goto done;
+    }
 
   rv = vnet_l2_patch_add_del (rx_sw_if_index, tx_sw_if_index, is_add);
 
@@ -348,17 +355,24 @@ test_patch_command_fn (vlib_main_t * vm,
       break;
 
     case VNET_API_ERROR_INVALID_SW_IF_INDEX:
-      return clib_error_return (0, "rx interface not a physical port");
+      error = clib_error_return (0, "rx interface not a physical port");
+      goto done;
 
     case VNET_API_ERROR_INVALID_SW_IF_INDEX_2:
-      return clib_error_return (0, "tx interface not a physical port");
+      error = clib_error_return (0, "tx interface not a physical port");
+      goto done;
 
     default:
-      return clib_error_return
+      error = clib_error_return
 	(0, "WARNING: vnet_l2_patch_add_del returned %d", rv);
+      goto done;
     }
 
-  return 0;
+
+done:
+  unformat_free (line_input);
+
+  return error;
 }
 
 /*?