memory leak in res_nsend()

[Daniel Jacobowitz]

On Mon, Oct 24, 2005 at 02:28:03PM +0400, Antony Dovgal wrote:
> Hello all.
> 
> I get memory leak after using res_nsend() and I don't see a regular way to 
> free the memory allocated in this function.
> That's what I can see in resolv/res_send.c (glibc-2.3.4):
> ...
>        for (ns = 0; ns < EXT(statp).nscount; ns++) {
>            n = map[ns];
>            if (EXT(statp).nsaddrs[n] == NULL)
>                EXT(statp).nsaddrs[n] =
>                    malloc(sizeof (struct sockaddr_in6)); /* malloc() */
>            if (EXT(statp).nsaddrs[n] != NULL) {
>                memcpy(EXT(statp).nsaddrs[n],
>                       &statp->nsaddr_list[ns],
>                       sizeof (struct sockaddr_in));
>                EXT(statp).nssocks[n] = -1;
>                n++;
>            }
>        }
> ...
> 
> But res_nclose() doesn't free those segments.
> That's what I've found in res_thread_freeres () function 
> (resolv/res_init.c):

Well, when you're running under valgrind, the freeres functions are
supposed to be called - for exactly this reason.  If it calls
__libc_freeres but not __libc_thread_freeres, maybe you shold report
this as a valgrind bug.


-- 
Daniel Jacobowitz
CodeSourcery, LLC