From owner-svn-src-stable@freebsd.org Fri Oct 4 17:27:50 2019 Return-Path: Delivered-To: svn-src-stable@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 6B91A1341C3; Fri, 4 Oct 2019 17:27:50 +0000 (UTC) (envelope-from emaste@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) server-signature RSA-PSS (4096 bits) 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 46lGzV28DYz4btx; Fri, 4 Oct 2019 17:27:50 +0000 (UTC) (envelope-from emaste@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 2CEAE27964; Fri, 4 Oct 2019 17:27:50 +0000 (UTC) (envelope-from emaste@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x94HRoJI008432; Fri, 4 Oct 2019 17:27:50 GMT (envelope-from emaste@FreeBSD.org) Received: (from emaste@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x94HRod9008431; Fri, 4 Oct 2019 17:27:50 GMT (envelope-from emaste@FreeBSD.org) Message-Id: <201910041727.x94HRod9008431@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: emaste set sender to emaste@FreeBSD.org using -f From: Ed Maste Date: Fri, 4 Oct 2019 17:27:50 +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: r353109 - stable/11/sys/kern X-SVN-Group: stable-11 X-SVN-Commit-Author: emaste X-SVN-Commit-Paths: stable/11/sys/kern X-SVN-Commit-Revision: 353109 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 04 Oct 2019 17:27:50 -0000 Author: emaste Date: Fri Oct 4 17:27:49 2019 New Revision: 353109 URL: https://svnweb.freebsd.org/changeset/base/353109 Log: MFC r352796: Check the vfs option length is valid before accessing through When a VFS option passed to nmount is present but NULL the kernel will place an empty option in its internal list. This will have a NULL pointer and a length of 0. When we come to read one of these the kernel will try to load from the last address of virtual memory. This is normally invalid so will fault resulting in a kernel panic. Fix this by checking if the length is valid before dereferencing. Modified: stable/11/sys/kern/vfs_mount.c Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/kern/vfs_mount.c ============================================================================== --- stable/11/sys/kern/vfs_mount.c Fri Oct 4 16:36:09 2019 (r353108) +++ stable/11/sys/kern/vfs_mount.c Fri Oct 4 17:27:49 2019 (r353109) @@ -591,7 +591,7 @@ vfs_donmount(struct thread *td, uint64_t fsflags, stru */ fstypelen = 0; error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); - if (error || fstype[fstypelen - 1] != '\0') { + if (error || fstypelen <= 0 || fstype[fstypelen - 1] != '\0') { error = EINVAL; if (errmsg != NULL) strncpy(errmsg, "Invalid fstype", errmsg_len); @@ -599,7 +599,7 @@ vfs_donmount(struct thread *td, uint64_t fsflags, stru } fspathlen = 0; error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); - if (error || fspath[fspathlen - 1] != '\0') { + if (error || fspathlen <= 0 || fspath[fspathlen - 1] != '\0') { error = EINVAL; if (errmsg != NULL) strncpy(errmsg, "Invalid fspath", errmsg_len);