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, 28 insertions, 14 deletions

diff --git a/src/plugins/sixrd/sixrd.c b/src/plugins/sixrd/sixrd.c
index 71fc181f..67a9a3ad 100644
--- a/src/plugins/sixrd/sixrd.c
+++ b/src/plugins/sixrd/sixrd.c
@@ -192,6 +192,7 @@ sixrd_add_domain_command_fn (vlib_main_t *vm,
   u32 num_m_args = 0;
   /* Optional arguments */
   u32 mtu = 0;
+  clib_error_t *error = 0;
 
   /* Get a line of input. */
   if (!unformat_user(input, unformat_line_input, line_input))
@@ -205,19 +206,25 @@ sixrd_add_domain_command_fn (vlib_main_t *vm,
       num_m_args++;
     else if (unformat(line_input, "mtu %d", &mtu))
       num_m_args++;
-    else
-      return clib_error_return(0, "unknown input `%U'",
-                               format_unformat_error, input);
+    else {
+      error = clib_error_return(0, "unknown input `%U'",
+                                format_unformat_error, line_input);
+      goto done;
+    }
   }
-  unformat_free(line_input);
 
-  if (num_m_args < 3)
-    return clib_error_return(0, "mandatory argument(s) missing");
+  if (num_m_args < 3) {
+    error = clib_error_return(0, "mandatory argument(s) missing");
+    goto done;
+  }
 
   sixrd_create_domain(&ip6_prefix, ip6_prefix_len, &ip4_prefix, ip4_prefix_len,
 		      &ip4_src, &sixrd_domain_index, mtu);
 
-  return 0;
+done:
+  unformat_free (line_input);
+
+  return error;
 }
 
 static clib_error_t *
@@ -228,6 +235,7 @@ sixrd_del_domain_command_fn (vlib_main_t *vm,
   unformat_input_t _line_input, *line_input = &_line_input;
   u32 num_m_args = 0;
   u32 sixrd_domain_index;
+  clib_error_t *error = 0;
 
   /* Get a line of input. */
   if (! unformat_user(input, unformat_line_input, line_input))
@@ -236,18 +244,24 @@ sixrd_del_domain_command_fn (vlib_main_t *vm,
   while (unformat_check_input(line_input) != UNFORMAT_END_OF_INPUT) {
     if (unformat(line_input, "index %d", &sixrd_domain_index))
       num_m_args++;
-    else
-      return clib_error_return(0, "unknown input `%U'",
-				format_unformat_error, input);
+    else {
+      error = clib_error_return(0, "unknown input `%U'",
+				format_unformat_error, line_input);
+      goto done;
+    }
   }
-  unformat_free(line_input);
 
-  if (num_m_args != 1)
-    return clib_error_return(0, "mandatory argument(s) missing");
+  if (num_m_args != 1) {
+    error = clib_error_return(0, "mandatory argument(s) missing");
+    goto done;
+  }
 
   sixrd_delete_domain(sixrd_domain_index);
 
-  return 0;
+done:
+  unformat_free (line_input);
+
+  return error;
 }
 
 static u8 *