Re: [RFA] Fix memory leak in gdbserver/hostio.c

[Michael Snyder <msnyder@vmware.com>]

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Pedro Alves wrote:
> On Sunday 27 February 2011 00:30:38, Michael Snyder wrote:
>> Found by coverity.
> 
> Do you try running coverity on your patches?
> 
>> @@ -367,6 +367,7 @@ handle_pwrite (char *own_buf, int packet
>>        || require_data (p, packet_len - (p - own_buf), &data, &len))
>>      {
>>        hostio_packet_error (own_buf);
>> +      free (data);
>>        return;
>>      }
> 
> This is wrong.  If any predicate other than require_data in if above
> returned true, then you'll be freeing a garbage pointer.  I'd
> fix this in require_data ... just free the output buffer when
> returning error, so the callers never have to.

Like this?


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2011-02-27  Michael Snyder  <msnyder@vmware.com>

	* hostio.c (require_data): Free malloc memory before returning
	error.

Index: hostio.c
===================================================================
RCS file: /cvs/src/src/gdb/gdbserver/hostio.c,v
retrieving revision 1.11
diff -u -p -u -p -r1.11 hostio.c
--- hostio.c	1 Jan 2011 15:33:24 -0000	1.11
+++ hostio.c	27 Feb 2011 21:48:00 -0000
@@ -134,7 +134,10 @@ require_data (char *p, int p_len, char *
     }
 
   if (escaped)
-    return -1;
+    {
+      xfree (data);
+      return -1;
+    }
 
   *data_len = output_index;
   return 0;