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, 40 insertions, 17 deletions

diff --git a/src/vnet/unix/tapcli.c b/src/vnet/unix/tapcli.c
index 48e81b5070e..25c930c6bfe 100644
--- a/src/vnet/unix/tapcli.c
+++ b/src/vnet/unix/tapcli.c
@@ -1308,6 +1308,7 @@ tap_connect_command_fn (vlib_main_t * vm,
   int ip6_address_set = 0;
   u32 ip4_mask_width = 0;
   u32 ip6_mask_width = 0;
+  clib_error_t *error = NULL;
 
   if (tm->is_disabled)
     return clib_error_return (0, "device disabled...");
@@ -1336,12 +1337,18 @@ tap_connect_command_fn (vlib_main_t * vm,
       else if (unformat (line_input, "%s", &intfc_name))
         ;
       else
-        return clib_error_return (0, "unknown input `%U'",
-                                  format_unformat_error, line_input);
+        {
+          error = clib_error_return (0, "unknown input `%U'",
+                                     format_unformat_error, line_input);
+          goto done;
+        }
     }
   
   if (intfc_name == 0)
-      return clib_error_return (0, "interface name must be specified");
+    {
+      error = clib_error_return (0, "interface name must be specified");
+      goto done;
+    }
 
   memset (ap, 0, sizeof (*ap));
 
@@ -1367,48 +1374,64 @@ tap_connect_command_fn (vlib_main_t * vm,
   switch (rv) 
     {
     case VNET_API_ERROR_SYSCALL_ERROR_1:
-      return clib_error_return (0, "Couldn't open /dev/net/tun");
+      error = clib_error_return (0, "Couldn't open /dev/net/tun");
+      goto done;
       
     case VNET_API_ERROR_SYSCALL_ERROR_2:
-      return clib_error_return (0, "Error setting flags on '%s'", intfc_name);
-  
+      error = clib_error_return (0, "Error setting flags on '%s'", intfc_name);
+      goto done;
+
     case VNET_API_ERROR_SYSCALL_ERROR_3:
-      return clib_error_return (0,  "Couldn't open provisioning socket");
+      error = clib_error_return (0,  "Couldn't open provisioning socket");
+      goto done;
 
     case VNET_API_ERROR_SYSCALL_ERROR_4:
-      return clib_error_return (0,  "Couldn't get if_index");
+      error = clib_error_return (0,  "Couldn't get if_index");
+      goto done;
     
     case VNET_API_ERROR_SYSCALL_ERROR_5:
-      return clib_error_return (0,  "Couldn't bind provisioning socket");
+      error = clib_error_return (0,  "Couldn't bind provisioning socket");
+      goto done;
 
     case VNET_API_ERROR_SYSCALL_ERROR_6:
-      return clib_error_return (0,  "Couldn't set device non-blocking flag");
+      error = clib_error_return (0,  "Couldn't set device non-blocking flag");
+      goto done;
 
     case VNET_API_ERROR_SYSCALL_ERROR_7:
-      return clib_error_return (0,  "Couldn't set device MTU");
+      error = clib_error_return (0,  "Couldn't set device MTU");
+      goto done;
 
     case VNET_API_ERROR_SYSCALL_ERROR_8:
-      return clib_error_return (0,  "Couldn't get interface flags");
+      error = clib_error_return (0,  "Couldn't get interface flags");
+      goto done;
 
     case VNET_API_ERROR_SYSCALL_ERROR_9:
-      return clib_error_return (0,  "Couldn't set intfc admin state up");
+      error = clib_error_return (0,  "Couldn't set intfc admin state up");
+      goto done;
 
     case VNET_API_ERROR_SYSCALL_ERROR_10:
-      return clib_error_return (0,  "Couldn't set intfc address/mask");
+      error = clib_error_return (0,  "Couldn't set intfc address/mask");
+      goto done;
 
     case VNET_API_ERROR_INVALID_REGISTRATION:
-      return clib_error_return (0,  "Invalid registration");
+      error = clib_error_return (0,  "Invalid registration");
+      goto done;
 
     case 0:
       break;
 
     default:
-      return clib_error_return (0,  "Unknown error: %d", rv);
+      error = clib_error_return (0,  "Unknown error: %d", rv);
+      goto done;
     }
 
   vlib_cli_output(vm, "%U\n", format_vnet_sw_if_index_name, 
                   vnet_get_main(), sw_if_index);
-  return 0;
+
+done:
+  unformat_free (line_input);
+
+  return error;
 }
 
 VLIB_CLI_COMMAND (tap_connect_command, static) = {