From nobody Sat Jan 08 04:29:33 2022 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 016B0193209F; Sat, 8 Jan 2022 04:29:35 +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 4JW6Yn5hF3z3Dfs; Sat, 8 Jan 2022 04:29:33 +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 40F6F18594; Sat, 8 Jan 2022 04:29:33 +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 2084TXns022272; Sat, 8 Jan 2022 04:29:33 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 2084TXFU022271; Sat, 8 Jan 2022 04:29:33 GMT (envelope-from git) Date: Sat, 8 Jan 2022 04:29:33 GMT Message-Id: <202201080429.2084TXFU022271@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Konstantin Belousov Subject: git: aec97963cd03 - main - msdosfs: do no allow lookup to return vdp except for dot lookups List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: kib X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: aec97963cd03f10e04083537ed449a84a5e42f87 Auto-Submitted: auto-generated ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1641616174; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=ztBFinkjP6JGJ2VUeASOrG3+BEdIGI/v5g2QZajFGV0=; b=xuiVhG3PjcGZvp7Q4xdFx+4kDRuyZmUWECBhKLbwJ5hEGml2bFUfzgB/1cSEEyWo1XyS5m CcOU3tg4uZG+O23hA3vh9GjGM4LHI5SQfGEa+At99vJ59sZ06ksKGL5f2nQEs49EPrVqkZ 55WoFGHdICh+Hlf2FF37IagC8ULGaUei6ezYHd8b1ByvyNJadG6+e1mFFt3osyG4eGoT5x 3vMZoz09icaCEVus1yIGB0LINGboN15mMjZXhSitjQdKXH1/tuNCWsLeMV6ke+gSFnVdLt TcX88B4iA1BVTXF1ES+wQhKvgI11DhxQWP7bv1fXp2sw0FNTurqPSHYMFZ6wnw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1641616174; a=rsa-sha256; cv=none; b=xaAi1qdNuPNxWmVYp5RvWsrtXY4lBPO3M1TqOHs8976xuBBJGmAbS0EbT8BoFDcaUWofQc y9NZrNARBxksuXz6G25AXoaZvZ88j1lwA+1od7a49iqj01l5dxlWBBqHPPJKIsoFsitLbJ jB2Ln5CePl9ksd+ZmK3yBLYv8UnTF76BOhOxO/o0mT5/QI0SlxVNw+X4wRw+CDXBCo2uI0 dj13gWmkZynUjttVX3bLcIwVIEARWC9n/XZhMxZE8/pdqFp/P4mQYV8W/Zu1qiXxIBeCxH Ac5vyiYyUM+1V7PwrN/Wvz0kVictjDxLVU981YBu+qRTa7Jeenb4rE+rEuzw4Q== ARC-Authentication-Results: i=1; mx1.freebsd.org; none X-ThisMailContainsUnwantedMimeParts: N The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=aec97963cd03f10e04083537ed449a84a5e42f87 commit aec97963cd03f10e04083537ed449a84a5e42f87 Author: Konstantin Belousov AuthorDate: 2021-12-26 21:51:48 +0000 Commit: Konstantin Belousov CommitDate: 2022-01-08 03:41:44 +0000 msdosfs: do no allow lookup to return vdp except for dot lookups In collaboaration with: pho Reviewed by: markj, mckusick Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D33721 --- sys/fs/msdosfs/msdosfs_lookup.c | 33 +++++++++++++++++++++++++++++---- 1 file changed, 29 insertions(+), 4 deletions(-) diff --git a/sys/fs/msdosfs/msdosfs_lookup.c b/sys/fs/msdosfs/msdosfs_lookup.c index 38bded459692..3db9665f6094 100644 --- a/sys/fs/msdosfs/msdosfs_lookup.c +++ b/sys/fs/msdosfs/msdosfs_lookup.c @@ -63,6 +63,28 @@ #include #include +static int +msdosfs_lookup_checker(struct msdosfsmount *pmp, struct vnode *dvp, + struct denode *tdp, struct vnode **vpp) +{ + struct vnode *vp; + + vp = DETOV(tdp); + + /* + * Lookup assumes that directory cannot be hardlinked. + * Corrupted msdosfs filesystem could break this assumption. + */ + if (vp == dvp) { + vput(vp); + *vpp = NULL; + return (EBADF); + } + + *vpp = vp; + return (0); +} + int msdosfs_lookup(struct vop_cachedlookup_args *ap) { @@ -501,8 +523,7 @@ foundroot: error = deget(pmp, cluster, blkoff, LK_EXCLUSIVE, &tdp); if (error) return (error); - *vpp = DETOV(tdp); - return (0); + return (msdosfs_lookup_checker(pmp, vdp, tdp, vpp)); } /* @@ -529,7 +550,9 @@ foundroot: if ((error = deget(pmp, cluster, blkoff, LK_EXCLUSIVE, &tdp)) != 0) return (error); - *vpp = DETOV(tdp); + if ((error = msdosfs_lookup_checker(pmp, vdp, tdp, vpp)) + != 0) + return (error); cnp->cn_flags |= SAVENAME; return (0); } @@ -572,6 +595,7 @@ foundroot: vput(*vpp); goto restart; } + return (msdosfs_lookup_checker(pmp, vdp, VTODE(*vpp), vpp)); } else if (dp->de_StartCluster == scn && isadir) { if (cnp->cn_namelen != 1 || cnp->cn_nameptr[0] != '.') { /* fs is corrupted, non-dot lookup returned dvp */ @@ -583,7 +607,8 @@ foundroot: if ((error = deget(pmp, cluster, blkoff, LK_EXCLUSIVE, &tdp)) != 0) return (error); - *vpp = DETOV(tdp); + if ((error = msdosfs_lookup_checker(pmp, vdp, tdp, vpp)) != 0) + return (error); } /*