From owner-svn-src-head@freebsd.org Wed Oct 2 15:45:49 2019 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 BB5E1132089; Wed, 2 Oct 2019 15:45:49 +0000 (UTC) (envelope-from markj@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 46k0pj4XlKz4b0f; Wed, 2 Oct 2019 15:45:49 +0000 (UTC) (envelope-from markj@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 7FCF52DB5C; Wed, 2 Oct 2019 15:45:49 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x92FjnBs031995; Wed, 2 Oct 2019 15:45:49 GMT (envelope-from markj@FreeBSD.org) Received: (from markj@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x92Fjntm031994; Wed, 2 Oct 2019 15:45:49 GMT (envelope-from markj@FreeBSD.org) Message-Id: <201910021545.x92Fjntm031994@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: markj set sender to markj@FreeBSD.org using -f From: Mark Johnston Date: Wed, 2 Oct 2019 15:45:49 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r353010 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: markj X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 353010 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: 2.1.29 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, 02 Oct 2019 15:45:49 -0000 Author: markj Date: Wed Oct 2 15:45:49 2019 New Revision: 353010 URL: https://svnweb.freebsd.org/changeset/base/353010 Log: Disallow fcntl(F_READAHEAD) when the vnode is not a regular file. The mountpoint may not have defined an iosize parameter, so an attempt to configure readahead on a device file can lead to a divide-by-zero crash. The sequential heuristic is not applied to I/O to or from device files, and posix_fadvise(2) returns an error when v_type != VREG, so perform the same check here. Reported by: syzbot+e4b682208761aa5bc53a@syzkaller.appspotmail.com Reviewed by: kib MFC after: 3 days Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D21864 Modified: head/sys/kern/kern_descrip.c Modified: head/sys/kern/kern_descrip.c ============================================================================== --- head/sys/kern/kern_descrip.c Wed Oct 2 15:19:39 2019 (r353009) +++ head/sys/kern/kern_descrip.c Wed Oct 2 15:45:49 2019 (r353010) @@ -788,6 +788,12 @@ kern_fcntl(struct thread *td, int fd, int cmd, intptr_ break; } vp = fp->f_vnode; + if (vp->v_type != VREG) { + fdrop(fp, td); + error = ENOTTY; + break; + } + /* * Exclusive lock synchronizes against f_seqcount reads and * writes in sequential_heuristic().