Use "tvb_get_string()" instead of allocating a (len+1)-sized buffer,

"tvb_memcpy()"ing to it, and putting in a null terminator;
"tvb_get_string()" will check whether all bytes of the string are
present before allocating the buffer, so that you don't leak memory if
the copy throws an exception, and don't crash if the length is absurdly
large.

Use "tvb_memdup()" instead of allocating a buffer and "tvb_memcpy()"ing
to it, so that an exception is thrown before you try to allocate the
buffer (for the same reasons as listed above).

Before allocating a buffer used when processing a chunk of data from a
packet, get a pointer to the chunk with "tvb_get_ptr()", or check that
the data is all there with "tvb_ensure_bytes_exist()", so that an
exception is thrown before you try to allocate the buffer (for the same
reasons as listed above).

Fix up the lengths of the tvbuff used when dissecting ONC RPC opaque data
with a particular dissector.

svn path=/trunk/; revision=10236

1 files changed, 11 insertions, 12 deletions

diff --git a/packet-enip.c b/packet-enip.c
index 2fe5f7a9b6..464c7080db 100644
--- a/packet-enip.c
+++ b/packet-enip.c
@@ -6,7 +6,7 @@
  * Magnus Hansson <mah@hms.se>
  * Joakim Wiberg <jow@hms.se>
  *
- * $Id: packet-enip.c,v 1.9 2004/02/04 20:34:53 guy Exp $
+ * $Id: packet-enip.c,v 1.10 2004/02/25 09:31:05 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -661,10 +661,11 @@ static const value_string enip_class_names_vals[] = {
 static proto_item*
 add_byte_array_text_to_proto_tree( proto_tree *tree, tvbuff_t *tvb, gint start, gint length, const char* str )
 {
-  char   *tmp, *tmp2, *tmp2start;
-  proto_item* pi;
-  int          i,tmp_length;
-  guint32      octet;
+  const char *tmp;
+  char       *tmp2, *tmp2start;
+  proto_item *pi;
+  int         i,tmp_length,tmp2_length;
+  guint32     octet;
   /* At least one version of Apple's C compiler/linker is buggy, causing
      a complaint from the linker about the "literal C string section"
      not ending with '\0' if we initialize a 16-element "char" array with
@@ -676,22 +677,21 @@ add_byte_array_text_to_proto_tree( proto_tree *tree, tvbuff_t *tvb, gint start,
         '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
 
 
-
    if( ( length * 2 ) > 32 )
    {
-      tmp2 = (char*)g_malloc( 36 );
       tmp_length = 16;
+      tmp2_length = 36;
    }
    else
    {
-      tmp2 = (char*)g_malloc( ( length * 2 ) + 1 );
       tmp_length = length;
+      tmp2_length = ( length * 2 ) + 1;
    }
 
-   tmp2start = tmp2;
+   tmp = tvb_get_ptr( tvb, start, tmp_length );
+   tmp2 = (char*)g_malloc( tmp2_length );
 
-   tmp = (char*)g_malloc( tmp_length );
-   tvb_memcpy( tvb, tmp, start, tmp_length );
+   tmp2start = tmp2;
 
    for( i = 0; i < tmp_length; i++ )
    {
@@ -713,7 +713,6 @@ add_byte_array_text_to_proto_tree( proto_tree *tree, tvbuff_t *tvb, gint start,
 
    pi = proto_tree_add_text( tree, tvb, start, length, "%s%s", str, tmp2start );
 
-   g_free( tmp );
    g_free( tmp2start );
 
    return( pi );