[Macsec] Fwd: zlib 1.1.4

[Eric Hall [EMAIL PROTECTED]]

On Mon, Mar 18, 2002 at 06:05:43PM -0500, Kee Hinckley wrote:
> At 3:22 PM -0500 3/18/02, Gordon Worley wrote:
> >This is what Apple had to say qua the zlib double free bug.  What do 
> >you guys think?  Should we trust them.  I'm planning to include zlib 
> >1.1.4 anyway.
> 
> I concur with Apple.  Everytime any application on my machine frees 
> memory that it shouldn't, the error is logged to the console.  That 
> means that the malloc library is tagging memory chunks and keeping 
> track of which were in fact properly allocated.  Given that, I don't 
> see how you could exploit an improper free.
> 
> (Also given that, there is no excuse for the number of applications 
> I've downloaded that screw up their memory allocation--but that's 
> another issue.)
> -- 

	I ran a double-free test w/ a snibbet of code from one of
the lists talking about the zlib bug, code, cc, and run are included
below.  From that test I too feel pretty good about OS X being
resistant to this particular bug.  System is a Pismo 500, OS X 10.1.3.


			-eric 


% cat a.c
       main()
        {
                char *p;

                p = malloc(256);
                p = malloc(256);
                free(p);
                free(p);
        }

% cc -o a a.c
a.c: In function `main':
a.c:5: warning: assignment makes pointer from integer without a cast
a.c:6: warning: assignment makes pointer from integer without a cast
% ./a
*** malloc[1194]: Deallocation of a pointer not malloced: 0x443c0; This could be a double free(), or free() called with the middle of an allocated block; Try setting environment variable MallocHelp to see tools to help debug
%


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