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Re: login-1.3 can't work on the recent snapshots.
On Wed, Jul 19, 2000 at 09:54:14PM +0200, Corinna Vinschen wrote:
>Chris Faylor wrote:
>> I'm not sure why it is a problem even for when child == myself,
>> actually.
>
>The below code could produce that (from spawn_guts):
>
>==== SNIP ====
> /* Remove impersonation */
> uid_t uid = geteuid();
> if (myself->impersonated && myself->token != INVALID_HANDLE_VALUE)
> seteuid (myself->orig_uid);
>
> /* Set child->uid to USHRT_MAX to force calling
>internal_getlogin()
> from child process. Set psid to NULL to play it safe. */
> child->uid = USHRT_MAX;
> child->psid = NULL;
>
> rc = CreateProcessAsUser (...);
>
> /* Restore impersonation */
> if (myself->impersonated && myself->token != INVALID_HANDLE_VALUE)
> seteuid (uid);
>==== SNAP ====
>
>Assuming that myself==child, the last part (restoring the impersonation)
>would be able to influence the child. The child would get a uid which
>is the wrong one and additionally forbids calling internal_getlogin.
>Hmm.
Ok. So, it seems like you just don't need to do the second seteuid when
mode == _P_OVERLAY . Right?
cgf