From owner-svn-src-all@freebsd.org Tue Sep 15 21:47:45 2020 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id A47863E156C; Tue, 15 Sep 2020 21:47:45 +0000 (UTC) (envelope-from gordon@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4BrcKF3tFlz3TFB; Tue, 15 Sep 2020 21:47:45 +0000 (UTC) (envelope-from gordon@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 68F12ED29; Tue, 15 Sep 2020 21:47:45 +0000 (UTC) (envelope-from gordon@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 08FLljtr046578; Tue, 15 Sep 2020 21:47:45 GMT (envelope-from gordon@FreeBSD.org) Received: (from gordon@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 08FLliAg046574; Tue, 15 Sep 2020 21:47:44 GMT (envelope-from gordon@FreeBSD.org) Message-Id: <202009152147.08FLliAg046574@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: gordon set sender to gordon@FreeBSD.org using -f From: Gordon Tetlow Date: Tue, 15 Sep 2020 21:47:44 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-releng@freebsd.org Subject: svn commit: r365781 - in releng: 11.3/libexec/ftpd 11.4/libexec/ftpd 12.1/libexec/ftpd 12.2/libexec/ftpd X-SVN-Group: releng X-SVN-Commit-Author: gordon X-SVN-Commit-Paths: in releng: 11.3/libexec/ftpd 11.4/libexec/ftpd 12.1/libexec/ftpd 12.2/libexec/ftpd X-SVN-Commit-Revision: 365781 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: 2.1.33 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, 15 Sep 2020 21:47:45 -0000 Author: gordon Date: Tue Sep 15 21:47:44 2020 New Revision: 365781 URL: https://svnweb.freebsd.org/changeset/base/365781 Log: Fix ftpd privilege escalation via ftpchroot. Approved by: so Approved by: re (implicit for releng/12.2) Security: FreeBSD-SA-20:30.ftpd Security: CVE-2020-7468 Modified: releng/11.3/libexec/ftpd/ftpd.c releng/11.4/libexec/ftpd/ftpd.c releng/12.1/libexec/ftpd/ftpd.c releng/12.2/libexec/ftpd/ftpd.c Modified: releng/11.3/libexec/ftpd/ftpd.c ============================================================================== --- releng/11.3/libexec/ftpd/ftpd.c Tue Sep 15 21:46:39 2020 (r365780) +++ releng/11.3/libexec/ftpd/ftpd.c Tue Sep 15 21:47:44 2020 (r365781) @@ -1593,13 +1593,20 @@ skip: * (uid 0 has no root power over NFS if not mapped explicitly.) */ if (seteuid(pw->pw_uid) < 0) { - reply(550, "Can't set uid."); - goto bad; + if (guest || dochroot) { + fatalerror("Can't set uid."); + } else { + reply(550, "Can't set uid."); + goto bad; + } } + /* + * Do not allow the session to live if we're chroot()'ed and chdir() + * fails. Otherwise the chroot jail can be escaped. + */ if (chdir(homedir) < 0) { if (guest || dochroot) { - reply(550, "Can't change to base directory."); - goto bad; + fatalerror("Can't change to base directory."); } else { if (chdir("/") < 0) { reply(550, "Root is inaccessible."); Modified: releng/11.4/libexec/ftpd/ftpd.c ============================================================================== --- releng/11.4/libexec/ftpd/ftpd.c Tue Sep 15 21:46:39 2020 (r365780) +++ releng/11.4/libexec/ftpd/ftpd.c Tue Sep 15 21:47:44 2020 (r365781) @@ -1593,13 +1593,20 @@ skip: * (uid 0 has no root power over NFS if not mapped explicitly.) */ if (seteuid(pw->pw_uid) < 0) { - reply(550, "Can't set uid."); - goto bad; + if (guest || dochroot) { + fatalerror("Can't set uid."); + } else { + reply(550, "Can't set uid."); + goto bad; + } } + /* + * Do not allow the session to live if we're chroot()'ed and chdir() + * fails. Otherwise the chroot jail can be escaped. + */ if (chdir(homedir) < 0) { if (guest || dochroot) { - reply(550, "Can't change to base directory."); - goto bad; + fatalerror("Can't change to base directory."); } else { if (chdir("/") < 0) { reply(550, "Root is inaccessible."); Modified: releng/12.1/libexec/ftpd/ftpd.c ============================================================================== --- releng/12.1/libexec/ftpd/ftpd.c Tue Sep 15 21:46:39 2020 (r365780) +++ releng/12.1/libexec/ftpd/ftpd.c Tue Sep 15 21:47:44 2020 (r365781) @@ -1595,13 +1595,20 @@ skip: * (uid 0 has no root power over NFS if not mapped explicitly.) */ if (seteuid(pw->pw_uid) < 0) { - reply(550, "Can't set uid."); - goto bad; + if (guest || dochroot) { + fatalerror("Can't set uid."); + } else { + reply(550, "Can't set uid."); + goto bad; + } } + /* + * Do not allow the session to live if we're chroot()'ed and chdir() + * fails. Otherwise the chroot jail can be escaped. + */ if (chdir(homedir) < 0) { if (guest || dochroot) { - reply(550, "Can't change to base directory."); - goto bad; + fatalerror("Can't change to base directory."); } else { if (chdir("/") < 0) { reply(550, "Root is inaccessible."); Modified: releng/12.2/libexec/ftpd/ftpd.c ============================================================================== --- releng/12.2/libexec/ftpd/ftpd.c Tue Sep 15 21:46:39 2020 (r365780) +++ releng/12.2/libexec/ftpd/ftpd.c Tue Sep 15 21:47:44 2020 (r365781) @@ -1595,13 +1595,20 @@ skip: * (uid 0 has no root power over NFS if not mapped explicitly.) */ if (seteuid(pw->pw_uid) < 0) { - reply(550, "Can't set uid."); - goto bad; + if (guest || dochroot) { + fatalerror("Can't set uid."); + } else { + reply(550, "Can't set uid."); + goto bad; + } } + /* + * Do not allow the session to live if we're chroot()'ed and chdir() + * fails. Otherwise the chroot jail can be escaped. + */ if (chdir(homedir) < 0) { if (guest || dochroot) { - reply(550, "Can't change to base directory."); - goto bad; + fatalerror("Can't change to base directory."); } else { if (chdir("/") < 0) { reply(550, "Root is inaccessible.");