From owner-dev-commits-src-main@freebsd.org Mon May 3 17:55:41 2021 Return-Path: Delivered-To: dev-commits-src-main@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 ACC1F638F34; Mon, 3 May 2021 17:55:41 +0000 (UTC) (envelope-from git@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 "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4FYrHK46lVz3K1N; Mon, 3 May 2021 17:55:41 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (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 did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 604C222459; Mon, 3 May 2021 17:55:41 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 143HtfSa046842; Mon, 3 May 2021 17:55:41 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 143HtfUP046841; Mon, 3 May 2021 17:55:41 GMT (envelope-from git) Date: Mon, 3 May 2021 17:55:41 GMT Message-Id: <202105031755.143HtfUP046841@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: 243b324f9668 - main - devfs: Avoid comparison with an uninitialized var in devfs_fp_check() MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 243b324f96686642177c8479c03288e2a6f68b50 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-main@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for the main branch of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 03 May 2021 17:55:41 -0000 The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=243b324f96686642177c8479c03288e2a6f68b50 commit 243b324f96686642177c8479c03288e2a6f68b50 Author: Mark Johnston AuthorDate: 2021-05-03 16:43:29 +0000 Commit: Mark Johnston CommitDate: 2021-05-03 17:24:30 +0000 devfs: Avoid comparison with an uninitialized var in devfs_fp_check() devvn_refthread() will initialize *devp only if it succeeds, so check for success before comparing with fp->f_data. Other devvn_refthread() callers are careful to do this. Reported by: KMSAN Reviewed by: kib Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D30068 --- sys/fs/devfs/devfs_vnops.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/sys/fs/devfs/devfs_vnops.c b/sys/fs/devfs/devfs_vnops.c index 043cee74fde2..40b80596523d 100644 --- a/sys/fs/devfs/devfs_vnops.c +++ b/sys/fs/devfs/devfs_vnops.c @@ -120,9 +120,8 @@ static int devfs_fp_check(struct file *fp, struct cdev **devp, struct cdevsw **dswp, int *ref) { - *dswp = devvn_refthread(fp->f_vnode, devp, ref); - if (*devp != fp->f_data) { + if (*dswp == NULL || *devp != fp->f_data) { if (*dswp != NULL) dev_relthread(*devp, *ref); return (ENXIO);