From owner-svn-src-all@freebsd.org Tue Feb 6 19:09:03 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id DAFCCEF3BA5; Tue, 6 Feb 2018 19:09:03 +0000 (UTC) (envelope-from mckusick@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 8B07479FF9; Tue, 6 Feb 2018 19:09:03 +0000 (UTC) (envelope-from mckusick@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 82A3C1BFD6; Tue, 6 Feb 2018 19:09:03 +0000 (UTC) (envelope-from mckusick@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id w16J93Lu042669; Tue, 6 Feb 2018 19:09:03 GMT (envelope-from mckusick@FreeBSD.org) Received: (from mckusick@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w16J93KW042667; Tue, 6 Feb 2018 19:09:03 GMT (envelope-from mckusick@FreeBSD.org) Message-Id: <201802061909.w16J93KW042667@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mckusick set sender to mckusick@FreeBSD.org using -f From: Kirk McKusick Date: Tue, 6 Feb 2018 19:09:03 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r328942 - in stable/11/lib/libc: gen sys X-SVN-Group: stable-11 X-SVN-Commit-Author: mckusick X-SVN-Commit-Paths: in stable/11/lib/libc: gen sys X-SVN-Commit-Revision: 328942 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 06 Feb 2018 19:09:04 -0000 Author: mckusick Date: Tue Feb 6 19:09:03 2018 New Revision: 328942 URL: https://svnweb.freebsd.org/changeset/base/328942 Log: MFC of 328304 and 328382. Do not dedup egid (group entry 0) Modified: stable/11/lib/libc/gen/getgrent.c stable/11/lib/libc/sys/setgroups.2 Directory Properties: stable/11/ (props changed) Modified: stable/11/lib/libc/gen/getgrent.c ============================================================================== --- stable/11/lib/libc/gen/getgrent.c Tue Feb 6 18:01:41 2018 (r328941) +++ stable/11/lib/libc/gen/getgrent.c Tue Feb 6 19:09:03 2018 (r328942) @@ -434,7 +434,7 @@ gr_addgid(gid_t gid, gid_t *groups, int maxgrp, int *g { int ret, dupc; - for (dupc = 0; dupc < MIN(maxgrp, *grpcnt); dupc++) { + for (dupc = 1; dupc < MIN(maxgrp, *grpcnt); dupc++) { if (groups[dupc] == gid) return 1; } Modified: stable/11/lib/libc/sys/setgroups.2 ============================================================================== --- stable/11/lib/libc/sys/setgroups.2 Tue Feb 6 18:01:41 2018 (r328941) +++ stable/11/lib/libc/sys/setgroups.2 Tue Feb 6 19:09:03 2018 (r328942) @@ -28,7 +28,7 @@ .\" @(#)setgroups.2 8.2 (Berkeley) 4/16/94 .\" $FreeBSD$ .\" -.Dd April 16, 1994 +.Dd January 19, 2018 .Dt SETGROUPS 2 .Os .Sh NAME @@ -56,6 +56,23 @@ more than .Dv {NGROUPS_MAX}+1 . .Pp Only the super-user may set a new group list. +.Pp +The first entry of the group array +.Pq Va gidset[0] +is used as the effective group-ID for the process. +This entry is over-written when a setgid program is run. +To avoid losing access to the privileges of the +.Va gidset[0] +entry, it should be duplicated later in the group array. +By convention, +this happens because the group value indicated +in the password file also appears in +.Pa /etc/group . +The group value in the password file is placed in +.Va gidset[0] +and that value then gets added a second time when the +.Pa /etc/group +file is scanned to create the group set. .Sh RETURN VALUES .Rv -std setgroups .Sh ERRORS