From nobody Wed Aug 07 13:44:39 2024 X-Original-To: dev-commits-src-branches@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 4WfBHX19TLz5S99d; Wed, 07 Aug 2024 13:44:40 +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 "R11" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4WfBHW6HlTz4jQY; Wed, 7 Aug 2024 13:44:39 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1723038279; 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=bvsv/o9mhKwWa9RMV8W7LHE+DILHbD58Sk+w373GdkM=; b=X0M0mqPYhT7DjC/y5iuM6TnqYNNVrNCInNLRyFkSzA5YkZDSDqZRglgR0BP+9DwOjUducm wUR8zP44e69eVw45Nw+9DaRflMMZipPxwGaWBAQptU3ZZD0L8Wa9hVWYcYJurLvzhfSlqV lwBlKnTIeBFXKQfoPP9PE9m0WIy/vhOk/k+Vin8OTlXh3nb5oBd0z3Qp0KU/Pbv6J77pw6 KbKBnmtDEGajyFj7oJM2Kx6rzcdESBLgATZK0k8Pu2IY8K/GqZ4k7U5UOsdbTShewkU5DK PD+W1ilK7PtAiKOg8rq+hmRn11UDTgUCL/75DBGzkSFNYutI9D/mFSctN5grOw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1723038279; a=rsa-sha256; cv=none; b=BmHtyOYffrF9YaT2+wDJdp2o6ZZoeEiNZwSIhN3m0asBjR/VcxKUl31z158aX5bkE3jtis 0zuvsXPPF+0v1zEx4P1FfMSTmSSC6iDqm4eGPFCcq2XWYrspmJzfA8RWvenXF++p8qOB/d bPTVUFfvMnU2TdNv9D+2Sd9lkvplcvNtp9ghKYFwcdca7T5yArQYlV1bzmq+IgeC5Taip0 s9wR81ObnwqMp1bRzcsZvhauwHVwL3cMuW67FsTnP+Kg2TBaVVUpmJYwjdaFpRSqesj/z8 7KT6jSOA90ObeSwSf4QEDoqvXc2ryBrf7UZVo6XSPRDXyAD4rr+JOsZQkShvKg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1723038279; 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=bvsv/o9mhKwWa9RMV8W7LHE+DILHbD58Sk+w373GdkM=; b=bK/0LdO8pNh30RrYLgZeYMAEyWjTH6sO/r85c8cdyIDW9s2p4ZMygF5XwPDYhKCKeEZNdw +z+wveG4SvEk1oMonmB9bKCnHClKHhOQqh9vRIH6uU9unXhvjT3b7W65mNcFKySc4bDN9/ 8pFUPXltKvFEDAl9K8ENnYKh+PhCsYYk9t7K0c/RzDuM+GBNbi1Eyuoi8ExtwI3q3HHkKs IptKSONw/YmhvcV2aC5Cyrcu0k4OWMvi9X6JNpk0BbrvpPqbDLybTnyfismLgtcHkwXHl/ BXzjM6muag223u3ysYaYpWiEYXyAvsk0nIizbc2Dh6xy26zsKAaTPR9s69tN8w== 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 4WfBHW5vR6zsrY; Wed, 7 Aug 2024 13:44:39 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.18.1/8.18.1) with ESMTP id 477DidpQ034007; Wed, 7 Aug 2024 13:44:39 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 477Did6b034004; Wed, 7 Aug 2024 13:44:39 GMT (envelope-from git) Date: Wed, 7 Aug 2024 13:44:39 GMT Message-Id: <202408071344.477Did6b034004@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: 4e7bf17e9db8 - releng/14.0 - nfscl: Scan readdir reply filenames for invalid characters List-Id: Commits to the stable branches of the FreeBSD src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-branches List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-branches@freebsd.org Sender: owner-dev-commits-src-branches@FreeBSD.org 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/releng/14.0 X-Git-Reftype: branch X-Git-Commit: 4e7bf17e9db892ab47ede6c12aa0d2902c5ff795 Auto-Submitted: auto-generated The branch releng/14.0 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=4e7bf17e9db892ab47ede6c12aa0d2902c5ff795 commit 4e7bf17e9db892ab47ede6c12aa0d2902c5ff795 Author: Rick Macklem AuthorDate: 2024-07-21 22:56:16 +0000 Commit: Mark Johnston CommitDate: 2024-08-07 13:25:36 +0000 nfscl: Scan readdir reply filenames for invalid characters The NFS RFCs are pretty loose with respect to what characters can be in a filename returned by a Readdir. However, FreeBSD, as a POSIX system will not handle imbedded '/' or nul characters in file names. Also, for NFSv4, the file names "." and ".." are handcrafted on the client and should not be returned by a NFSv4 server. This patch scans for the above in filenames returned by Readdir and ignores any entry returned by Readdir which has them in it. Because an imbedded nul would be a string terminator, it was not possible to code this check efficiently using string(3) functions. Approved by: so Security: FreeBSD-SA-24:07.nfsclient Security: CVE-2024-6759 Reported by: Apple Security Engineering and Architecture (SEAR) (cherry picked from commit 026cdaa3b3a92574d9ac3155216e5cc0b0bd4c51) (cherry picked from commit 9328ded386d570c8455b9021e047520ef72e0e79) --- sys/fs/nfsclient/nfs_clrpcops.c | 137 ++++++++++++++++++++++++++++++++-------- 1 file changed, 110 insertions(+), 27 deletions(-) diff --git a/sys/fs/nfsclient/nfs_clrpcops.c b/sys/fs/nfsclient/nfs_clrpcops.c index 7f886ad286e7..c63bff726c87 100644 --- a/sys/fs/nfsclient/nfs_clrpcops.c +++ b/sys/fs/nfsclient/nfs_clrpcops.c @@ -142,6 +142,7 @@ static int nfsrpc_createv4(vnode_t , char *, int, struct vattr *, nfsquad_t, int, struct nfsclowner *, struct nfscldeleg **, struct ucred *, NFSPROC_T *, struct nfsvattr *, struct nfsvattr *, struct nfsfh **, int *, int *, int *); +static bool nfscl_invalidfname(bool, char *, int); static int nfsrpc_locku(struct nfsrv_descript *, struct nfsmount *, struct nfscllockowner *, u_int64_t, u_int64_t, u_int32_t, struct ucred *, NFSPROC_T *, int); @@ -3224,6 +3225,31 @@ nfsrpc_rmdir(vnode_t dvp, char *name, int namelen, struct ucred *cred, return (error); } +/* + * Check to make sure the file name in a Readdir reply is valid. + */ +static bool +nfscl_invalidfname(bool is_v4, char *name, int len) +{ + int i; + char *cp; + + if (is_v4 && ((len == 1 && name[0] == '.') || + (len == 2 && name[0] == '.' && name[1] == '.'))) { + printf("Readdir NFSv4 reply has dot or dotdot in it\n"); + return (true); + } + cp = name; + for (i = 0; i < len; i++, cp++) { + if (*cp == '/' || *cp == '\0') { + printf("Readdir reply file name had imbedded / or nul" + " byte\n"); + return (true); + } + } + return (false); +} + /* * Readdir rpc. * Always returns with either uio_resid unchanged, if you are at the @@ -3276,6 +3302,8 @@ nfsrpc_readdir(vnode_t vp, struct uio *uiop, nfsuint64 *cookiep, KASSERT(uiop->uio_iovcnt == 1 && (uiop->uio_resid & (DIRBLKSIZ - 1)) == 0, ("nfs readdirrpc bad uio")); + KASSERT(uiop->uio_segflg == UIO_SYSSPACE, + ("nfsrpc_readdir: uio userspace")); ncookie.lval[0] = ncookie.lval[1] = 0; /* * There is no point in reading a lot more than uio_resid, however @@ -3533,6 +3561,17 @@ nfsrpc_readdir(vnode_t vp, struct uio *uiop, nfsuint64 *cookiep, uiop->uio_resid) bigenough = 0; if (bigenough) { + struct iovec saviov; + off_t savoff; + ssize_t savresid; + int savblksiz; + + saviov.iov_base = uiop->uio_iov->iov_base; + saviov.iov_len = uiop->uio_iov->iov_len; + savoff = uiop->uio_offset; + savresid = uiop->uio_resid; + savblksiz = blksiz; + dp = (struct dirent *)uiop->uio_iov->iov_base; dp->d_pad0 = dp->d_pad1 = 0; dp->d_off = 0; @@ -3548,20 +3587,35 @@ nfsrpc_readdir(vnode_t vp, struct uio *uiop, nfsuint64 *cookiep, uiop->uio_iov->iov_base = (char *)uiop->uio_iov->iov_base + DIRHDSIZ; uiop->uio_iov->iov_len -= DIRHDSIZ; + cp = uiop->uio_iov->iov_base; error = nfsm_mbufuio(nd, uiop, len); if (error) goto nfsmout; - cp = uiop->uio_iov->iov_base; - tlen -= len; - NFSBZERO(cp, tlen); - cp += tlen; /* points to cookie storage */ - tl2 = (u_int32_t *)cp; - uiop->uio_iov->iov_base = - (char *)uiop->uio_iov->iov_base + tlen + - NFSX_HYPER; - uiop->uio_iov->iov_len -= tlen + NFSX_HYPER; - uiop->uio_resid -= tlen + NFSX_HYPER; - uiop->uio_offset += (tlen + NFSX_HYPER); + /* Check for an invalid file name. */ + if (nfscl_invalidfname( + (nd->nd_flag & ND_NFSV4) != 0, cp, len)) { + /* Skip over this entry. */ + uiop->uio_iov->iov_base = + saviov.iov_base; + uiop->uio_iov->iov_len = + saviov.iov_len; + uiop->uio_offset = savoff; + uiop->uio_resid = savresid; + blksiz = savblksiz; + } else { + cp = uiop->uio_iov->iov_base; + tlen -= len; + NFSBZERO(cp, tlen); + cp += tlen; /* points to cookie store */ + tl2 = (u_int32_t *)cp; + uiop->uio_iov->iov_base = + (char *)uiop->uio_iov->iov_base + + tlen + NFSX_HYPER; + uiop->uio_iov->iov_len -= tlen + + NFSX_HYPER; + uiop->uio_resid -= tlen + NFSX_HYPER; + uiop->uio_offset += (tlen + NFSX_HYPER); + } } else { error = nfsm_advance(nd, NFSM_RNDUP(len), -1); if (error) @@ -3727,6 +3781,8 @@ nfsrpc_readdirplus(vnode_t vp, struct uio *uiop, nfsuint64 *cookiep, KASSERT(uiop->uio_iovcnt == 1 && (uiop->uio_resid & (DIRBLKSIZ - 1)) == 0, ("nfs readdirplusrpc bad uio")); + KASSERT(uiop->uio_segflg == UIO_SYSSPACE, + ("nfsrpc_readdirplus: uio userspace")); ncookie.lval[0] = ncookie.lval[1] = 0; timespecclear(&dctime); *attrflagp = 0; @@ -3962,6 +4018,17 @@ nfsrpc_readdirplus(vnode_t vp, struct uio *uiop, nfsuint64 *cookiep, uiop->uio_resid) bigenough = 0; if (bigenough) { + struct iovec saviov; + off_t savoff; + ssize_t savresid; + int savblksiz; + + saviov.iov_base = uiop->uio_iov->iov_base; + saviov.iov_len = uiop->uio_iov->iov_len; + savoff = uiop->uio_offset; + savresid = uiop->uio_resid; + savblksiz = blksiz; + dp = (struct dirent *)uiop->uio_iov->iov_base; dp->d_pad0 = dp->d_pad1 = 0; dp->d_off = 0; @@ -3980,25 +4047,41 @@ nfsrpc_readdirplus(vnode_t vp, struct uio *uiop, nfsuint64 *cookiep, cnp->cn_nameptr = uiop->uio_iov->iov_base; cnp->cn_namelen = len; NFSCNHASHZERO(cnp); + cp = uiop->uio_iov->iov_base; error = nfsm_mbufuio(nd, uiop, len); if (error) goto nfsmout; - cp = uiop->uio_iov->iov_base; - tlen -= len; - NFSBZERO(cp, tlen); - cp += tlen; /* points to cookie storage */ - tl2 = (u_int32_t *)cp; - if (len == 2 && cnp->cn_nameptr[0] == '.' && - cnp->cn_nameptr[1] == '.') - isdotdot = 1; - else - isdotdot = 0; - uiop->uio_iov->iov_base = - (char *)uiop->uio_iov->iov_base + tlen + - NFSX_HYPER; - uiop->uio_iov->iov_len -= tlen + NFSX_HYPER; - uiop->uio_resid -= tlen + NFSX_HYPER; - uiop->uio_offset += (tlen + NFSX_HYPER); + /* Check for an invalid file name. */ + if (nfscl_invalidfname( + (nd->nd_flag & ND_NFSV4) != 0, cp, len)) { + /* Skip over this entry. */ + uiop->uio_iov->iov_base = + saviov.iov_base; + uiop->uio_iov->iov_len = + saviov.iov_len; + uiop->uio_offset = savoff; + uiop->uio_resid = savresid; + blksiz = savblksiz; + } else { + cp = uiop->uio_iov->iov_base; + tlen -= len; + NFSBZERO(cp, tlen); + cp += tlen; /* points to cookie store */ + tl2 = (u_int32_t *)cp; + if (len == 2 && + cnp->cn_nameptr[0] == '.' && + cnp->cn_nameptr[1] == '.') + isdotdot = 1; + else + isdotdot = 0; + uiop->uio_iov->iov_base = + (char *)uiop->uio_iov->iov_base + + tlen + NFSX_HYPER; + uiop->uio_iov->iov_len -= tlen + + NFSX_HYPER; + uiop->uio_resid -= tlen + NFSX_HYPER; + uiop->uio_offset += (tlen + NFSX_HYPER); + } } else { error = nfsm_advance(nd, NFSM_RNDUP(len), -1); if (error)