Milter-greylist

On Thu, Sep 05, 2013 at 02:05:56AM +0200, manu@... wrote:
[..]
> Index: milter-greylist.c
> ===================================================================
> RCS file: /cvsroot/milter-greylist/milter-greylist.c,v
> retrieving revision 1.269
> retrieving revision 1.270
> diff -U 4 -r1.269 -r1.270
> --- milter-greylist.c   1 Sep 2013 04:59:42 -0000       1.269
> +++ milter-greylist.c   4 Sep 2013 23:58:30 -0000       1.270
> @@ -3800,14 +3800,16 @@
>                 }
>  
>                 src = priv->priv_sr.sr_msg_x;
>                 for (i = 0; i < lcount; i++) {
> -                       if ((lbufs[i] = strndup(src, MAXREPLYLEN)) == NULL) {
> +                       if ((lbufs[i] = malloc(MAXREPLYLEN + 1)) == NULL) {
>                                 mg_log(LOG_ERR, "strndup failed: %s",
>                                        strerror(errno));
>                                 exit(EX_OSERR);
>                         }
>  
> +                       (void)strncpy(lbufs[i], src, MAXREPLYLEN);
> +
>                         src += MAXREPLYLEN;             
>                 }
>  
>                 lbufs[i] = NULL;

These changes seem to be not equivalent.
strndup() has other properties:

 * the patch code always creates in lbuf[i] a MAXREPLYLEN + 1 sized buffer - strndup()
   doesn't if the length of src is less than MAXREPLYLEN.
	if (strlen(src) <= MAXREPLYLEN) {
		lbufs[i] = strdup(src);
	}
	else {
		if ((lbufs[i] = malloc(MAXREPLYLEN + 1)) == NULL) {
		[..]

 * strndup() always null-terminates the destination. strncpy doesn't if
	length of src is greater or equal MAXREPLYLEN.
	Above after strncpy()
		lbufs[i][MAXREPLYLEN] = 0;
	is missing.
	malloc() does not guarantee that the allocate memory is zeroed.


Johann