Hi Pierre,
On Jan 12 11:16, Pierre A. Humblet wrote:
> cvs diff -up minires-os-if.c
> Index: minires-os-if.c
> ===================================================================
> RCS file: /cvs/src/src/winsup/cygwin/libc/minires-os-if.c,v
> retrieving revision 1.15
> diff -u -p -r1.15 minires-os-if.c
> --- minires-os-if.c 23 Apr 2013 09:44:35 -0000 1.15
> +++ minires-os-if.c 12 Jan 2015 03:39:27 -0000
> @@ -249,6 +249,13 @@ static int cygwin_query(res_state statp,
> rr = pQueryResultsSet;
> section = 0;
> while (rr) {
> + /* Some Windows versions return questions when providing locally
> + generated answers, for example for "localhost" or for the computer
> name */
> + if (((rr->Flags.DW & 0x3) == DnsSectionQuestion) &&
> + (rr->wDataLength > 0)) {
> + DPRINTF(debug, "Changing record below from question to answer\n");
> + rr->Flags.DW ^= DnsSectionQuestion ^ DnsSectionAnswer;
> + }
> if (!counts[0] && (rr->Flags.DW & 0x3)) {
> /* No question. Adopt the first name as the name in the question */
> if ((len = dn_comp(rr->pName, ptr, AnsLength - 4,
Thanks, patch applied. Somehow the indentation was totally broken in
your patch, though.
> Now the bad news: the exim daemon crashes.
>
> The reason is this:
> $ getent passwd exim
> NT SERVICE+exim:*:376394:376394:U-NT
> SERVICE\exim,S-1-5-80-3213360373-4072665756-2198108471-1641386292-839958090:/:/sbin/nologin
>
> So even though I am requesting just "exim" I am getting an entry for "NT
> SERVICE+exim"
That's definitely a bug and I can easily reproduce it. I'm not sure yet
how this happens, but this is really not ok. I'll have a look ASAP.
> Talk about aliasing.
> The way the exim code works, when an "exim" user exists (per getpwnam)
> the daemon setuids to it.
> Here it's trying to setuid to a service.
> This would break every exim installation.
Nevertheless, quite apart from the above, your code should be able to
live with a prefixed user account. If the exim account is a local
account, and if the machine is an AD member, the account will be named
"MACHINE+exim". But still, when calling getpwnam("exim"), it won't
return the entry for "MACHINE+exim". Rather you should call cygwin_internal
as OpenSSH and postfix do now, kind of like this:
char exim_username[DNLEN + UNLEN + 2];
if (cygwin_internal (CW_CYGNAME_FROM_WINNAME, "exim", exim_username,
sizeof exim_username) != 0)
strcpy (cyg_privsep_user, "exim");
/* Call getpwnam */
struct passwd *pw = getpwnam (exim_username);
Thanks,
Corinna
--
Corinna Vinschen Please, send mails regarding Cygwin to
Cygwin Maintainer cygwin AT cygwin DOT com
Red Hat
pgpmCB0ZQjTQX.pgp
Description: PGP signature
