From owner-dev-commits-src-main@freebsd.org Sun Jan 3 06:53:12 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 A91744C777D; Sun, 3 Jan 2021 06:53:12 +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 "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4D7qGJ4S7Nz4WmV; Sun, 3 Jan 2021 06:53:12 +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 8B73A2380E; Sun, 3 Jan 2021 06:53:12 +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 1036rCkp023170; Sun, 3 Jan 2021 06:53:12 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 1036rCbO023169; Sun, 3 Jan 2021 06:53:12 GMT (envelope-from git) Date: Sun, 3 Jan 2021 06:53:12 GMT Message-Id: <202101030653.1036rCbO023169@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mateusz Guzik Subject: git: 30a2fc91fa5a - main - cache: postpone NAME_MAX check as it may be unnecessary MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: mjg X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 30a2fc91fa5a0fa8717da788cc18073cca786c05 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: Sun, 03 Jan 2021 06:53:12 -0000 The branch main has been updated by mjg: URL: https://cgit.FreeBSD.org/src/commit/?id=30a2fc91fa5a0fa8717da788cc18073cca786c05 commit 30a2fc91fa5a0fa8717da788cc18073cca786c05 Author: Mateusz Guzik AuthorDate: 2020-12-31 07:28:32 +0000 Commit: Mateusz Guzik CommitDate: 2021-01-03 06:50:06 +0000 cache: postpone NAME_MAX check as it may be unnecessary --- sys/kern/vfs_cache.c | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-) diff --git a/sys/kern/vfs_cache.c b/sys/kern/vfs_cache.c index e6f446d2d0e2..b4882079790d 100644 --- a/sys/kern/vfs_cache.c +++ b/sys/kern/vfs_cache.c @@ -2230,6 +2230,9 @@ cache_enter_time(struct vnode *dvp, struct vnode *vp, struct componentname *cnp, int flag; int len; + KASSERT(cnp->cn_namelen <= NAME_MAX, + ("%s: passed len %ld exceeds NAME_MAX (%d)", __func__, cnp->cn_namelen, + NAME_MAX)); VNPASS(dvp != vp, dvp); VNPASS(!VN_IS_DOOMED(dvp), dvp); VNPASS(dvp->v_type != VNON, dvp); @@ -4310,6 +4313,14 @@ cache_fplookup_noentry(struct cache_fpl *fpl) MPASS((cnp->cn_flags & ISDOTDOT) == 0); MPASS(!cache_fpl_isdotdot(cnp)); + /* + * Hack: delayed name len checking. + */ + if (__predict_false(cnp->cn_namelen > NAME_MAX)) { + cache_fpl_smr_exit(fpl); + return (cache_fpl_handled(fpl, ENAMETOOLONG)); + } + if (cnp->cn_nameiop != LOOKUP) { fpl->tvp = NULL; return (cache_fplookup_modifying(fpl)); @@ -4834,13 +4845,15 @@ cache_fplookup_parse(struct cache_fpl *fpl) cnp->cn_nameptr[ndp->ni_pathlen - 1] = '\0'; cnp->cn_namelen = cp - cnp->cn_nameptr; - if (__predict_false(cnp->cn_namelen > NAME_MAX)) { - cache_fpl_smr_exit(fpl); - return (cache_fpl_handled(fpl, ENAMETOOLONG)); - } ndp->ni_pathlen -= cnp->cn_namelen; KASSERT(ndp->ni_pathlen <= PATH_MAX, ("%s: ni_pathlen underflow to %zd\n", __func__, ndp->ni_pathlen)); + /* + * Hack: we have to check if the found path component's length exceeds + * NAME_MAX. However, the condition is very rarely true and check can + * be elided in the common case -- if an entry was found in the cache, + * then it could not have been too long to begin with. + */ ndp->ni_next = cp; #ifdef INVARIANTS @@ -4888,12 +4901,22 @@ cache_fplookup_parse_advance(struct cache_fpl *fpl) static int __noinline cache_fplookup_failed_vexec(struct cache_fpl *fpl, int error) { + struct componentname *cnp; struct vnode *dvp; seqc_t dvp_seqc; + cnp = fpl->cnp; dvp = fpl->dvp; dvp_seqc = fpl->dvp_seqc; + /* + * Hack: delayed name len checking. + */ + if (__predict_false(cnp->cn_namelen > NAME_MAX)) { + cache_fpl_smr_exit(fpl); + return (cache_fpl_handled(fpl, ENAMETOOLONG)); + } + /* * Hack: they may be looking up foo/bar, where foo is a * regular file. In such a case we need to turn ENOTDIR,