From owner-svn-src-head@freebsd.org Wed Jul 22 21:44:52 2020 Return-Path: Delivered-To: svn-src-head@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 9F570361DDE; Wed, 22 Jul 2020 21:44:52 +0000 (UTC) (envelope-from brooks@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 4BBpsJ3TQfz4p6w; Wed, 22 Jul 2020 21:44:52 +0000 (UTC) (envelope-from brooks@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 5B060E3BE; Wed, 22 Jul 2020 21:44:52 +0000 (UTC) (envelope-from brooks@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 06MLiqx0088497; Wed, 22 Jul 2020 21:44:52 GMT (envelope-from brooks@FreeBSD.org) Received: (from brooks@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 06MLiqjq088496; Wed, 22 Jul 2020 21:44:52 GMT (envelope-from brooks@FreeBSD.org) Message-Id: <202007222144.06MLiqjq088496@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: brooks set sender to brooks@FreeBSD.org using -f From: Brooks Davis Date: Wed, 22 Jul 2020 21:44:52 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r363435 - head/usr.sbin/mountd X-SVN-Group: head X-SVN-Commit-Author: brooks X-SVN-Commit-Paths: head/usr.sbin/mountd X-SVN-Commit-Revision: 363435 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 Jul 2020 21:44:52 -0000 Author: brooks Date: Wed Jul 22 21:44:51 2020 New Revision: 363435 URL: https://svnweb.freebsd.org/changeset/base/363435 Log: Avoid reading one byte before the path buffer. This happens when there's only one component (e.g. "/foo"). This (mostly-harmless) bug has been present since June 1990 when it was commited to mountd.c SCCS version 5.9. Note: the bug is on the second changed line, the first line is changed for visual consistency. Reviewed by: cem, emaste, mckusick, rmacklem Found with: CHERI Obtained from: CheriBSD MFC after: 1 week Sponsored by: DARPA Differential Revision: https://reviews.freebsd.org/D25759 Modified: head/usr.sbin/mountd/mountd.c Modified: head/usr.sbin/mountd/mountd.c ============================================================================== --- head/usr.sbin/mountd/mountd.c Wed Jul 22 21:30:18 2020 (r363434) +++ head/usr.sbin/mountd/mountd.c Wed Jul 22 21:44:51 2020 (r363435) @@ -3155,9 +3155,9 @@ do_mount(struct exportlist *ep, struct grouplist *grp, goto error_exit; } /* back up over the last component */ - while (*cp == '/' && cp > dirp) + while (cp > dirp && *cp == '/') cp--; - while (*(cp - 1) != '/' && cp > dirp) + while (cp > dirp && *(cp - 1) != '/') cp--; if (cp == dirp) { if (debug)