[email protected], le jeu. 10 sept. 2026 20:19:09 +0200, a ecrit: > Sep 10, 2026, 17:49 by [email protected]: > > > [email protected], le jeu. 10 sept. 2026 19:31:03 +0200, a ecrit: > > > >> Sep 10, 2026, 16:45 by [email protected]: > >> > >> >> Is this a bug in Hurd or in glibc/nscd? > >> >> Changing the nscd lookup to insert the group name at the beginning > >> >> instead of the end would fix it > >> >> > >> > > >> > Perhaps we just need to fix glibc's setgroups to make sure that the > >> > current effective gid is first in the list given to the auth server, > >> > fixing the order if needed. > >> > >> Fixing setgroups is not enough because i.e. _merge_implied_gids also > >> assumes that the pw_gid is first for setgrouplist and does not use > >> setgroups. > >> > > > > But doesn't it properly cope with keeping the first element first? > > > Yes it does. It is just that it gets the gid list from getgrouplist which > might or might not have the pw_gid as the first element. Should that add the > primary gid explicitly first and then merge the other gids afterwards?
The primary gid will be first in the list.to be processed by idvec_merge_ids, and idvec_merge will leave the first element of implied_gids as it is. > > The only way that applications have to modify the list without knowing > > about the hurd convention is setgroups, as seen from a unix view. So > > that's the only place that needs to take care of the conversion of > > convention, and everything below can just keep the hurd convention > > correct. > > > >> Wouldnt it be netter to ensure this in __nscd_getgrouplist to prepend the > >> group instead of appending it and make the normal and nscd output > >> identical? > >> > > > > That will only fix nscd. We want glibc to expose a unix behavior, so we > > have to fix it when it happens not to. > > > Once the list reaches setgroups there is no special gid anymore (apart from > the hurd convention). How is setgroups supposed to know what the extra gid > specified in the call to getgrouplist was and potentially "correct" the list? It can use getegid(). Samuel
