From nobody Thu Jan 16 18:08:21 2025 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 4YYrT23wXHz5kktl; Thu, 16 Jan 2025 18:08:22 +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 4YYrT20f05z3RPX; Thu, 16 Jan 2025 18:08:22 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1737050902; 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=W+4yyTVl72b2Fm3bjvMpkDs18T8aq//CxJmENLWptos=; b=EJCeRipBrmh/h84VuFBKc7EkRQrUvURMFRD/i3KpPRAMmYZfIy3zgKc4sws4vzWxSy5VVu 1Xd0YQeLgHsaz4IfkxiG67gPq7P2g07o75TAAELZ+4a8bcNFSbFHeM97ivMQ1P/Q0AjL01 DyiErnt4IJND134cdC5gk27Q5WnTmUjHPOU0ZAHVYYkDpV5uLP0wWzk5AXkW02Vr+YzBNI 1dy/qdoZ8sBUHxD1n2O0g+phjjjYeqZu3i4vw9qPgPy98A4+DyhgZo2PXvrzkKk995JqNi aALRR+e03J/kIEhS6Hj1NzRVDMgAwWeMpYumgxMmKREnOOKc7v/H7fZEoTHd7Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1737050902; 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=W+4yyTVl72b2Fm3bjvMpkDs18T8aq//CxJmENLWptos=; b=vmjZfsz7PPYky8BsbxhLu7MIBd6Cvt1CFFloI57ndHF1eD5w9GTYYCp7eUYi1NX6pcTl4a 2sT3h6WdSqmcgYZCkHK7/Py4tOgwrilBiABf08uZ/aalkHpK2KF5bxW++xpHpsEiIdZy22 M5I+qHqg36SlsSrWOcN7iMVR0X/SGX3cX7FWB+/bdxQZsiBeMQnVXhTxlt7CEJ6iEOXleE N+KysFJQVeGyThmVvGS9FkrmDOFL8Tc46VekOgm0y10zYfr3hSi9/F5Iwg0UMej4EYZ6Xw Mo+Hky6+rQ70EeUCLUNoJqrnWktxoVzSrVIR73YjqAFQxv6D2uuy8Wso3RCZkA== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1737050902; a=rsa-sha256; cv=none; b=EMXYuwjfpB207wrWtnugufMVQq+IwmpTQEb/YqSIjcpq+2hxroibyWz1wsrVW2NJ6tbe6O 8yLNPdmItoyXJtiy9TsOnLRrC3wxI0ffRw0Ti3SggYMQZRSQfHhakf5yd5F60V5YHaXagU 6pq5mbfgDBit7P+5K1nVkZqeHvmxSb9ZF4CvCu95Ux52NOxoB7jqAWfEme4NX7giQHJWDf cpUym4S0RiDt1NSv+yhhb4TJ1SBVaOZN1T2krl3aucF6s9vlx3jH0FSCdYfn/XYet4OZmW Nqr7B/Zq+0KEGq0SUU3XqXMNkNSWD6l5tYVGJdr4GoGZoLLIK9Q5up1hdcYbPA== ARC-Authentication-Results: i=1; mx1.freebsd.org; none 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 4YYrT206HKzjby; Thu, 16 Jan 2025 18:08:22 +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 50GI8Lmw092105; Thu, 16 Jan 2025 18:08:21 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 50GI8LsE092102; Thu, 16 Jan 2025 18:08:21 GMT (envelope-from git) Date: Thu, 16 Jan 2025 18:08:21 GMT Message-Id: <202501161808.50GI8LsE092102@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Olivier Certner Subject: git: fb651b231863 - stable/14 - mountd(8): parsecred(): Fallback to "nogroup" or GID_NOGROUP 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: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: olce X-Git-Repository: src X-Git-Refname: refs/heads/stable/14 X-Git-Reftype: branch X-Git-Commit: fb651b2318631eeceb08dc8ef88e868887ce362e Auto-Submitted: auto-generated The branch stable/14 has been updated by olce: URL: https://cgit.FreeBSD.org/src/commit/?id=fb651b2318631eeceb08dc8ef88e868887ce362e commit fb651b2318631eeceb08dc8ef88e868887ce362e Author: Olivier Certner AuthorDate: 2024-10-08 09:21:17 +0000 Commit: Olivier Certner CommitDate: 2025-01-16 18:06:57 +0000 mountd(8): parsecred(): Fallback to "nogroup" or GID_NOGROUP In the 'uid:gid:gid:...' case (for '-maproot' or '-mapall'), if no GID is specified at all (i.e., input is of the form 'uid:', with the colon at the end), mountd(8) would pass credentials with an empty array of groups to the kernel. For security reasons, we have put in place a kernel fallback a while ago, which is to use the single group GID_NOGROUP (see commits cfbe7a62dc62 ("nfs, rpc: Ensure kernel credentials have at least one group") and 5169d4307eb9 ("nfs: Fallback to GID_NOGROUP on no groups")). Here, as we are in userland, we first try to find the GID number corresponding to "nogroup", and only then fall back to GID_NOGROUP, as nfsuserd(8) does. Approved by: markj (mentor) MFC after: 2 weeks Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D47011 (cherry picked from commit bdc259ef382f76b1821d4356049d5b856c42901a) --- usr.sbin/mountd/mountd.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) diff --git a/usr.sbin/mountd/mountd.c b/usr.sbin/mountd/mountd.c index f7ab5d6d696d..8ee8280b5d67 100644 --- a/usr.sbin/mountd/mountd.c +++ b/usr.sbin/mountd/mountd.c @@ -277,6 +277,8 @@ static int xdr_mlist(XDR *, caddr_t); static void terminate(int); static void cp_cred(struct expcred *, struct expcred *); +static gid_t nogroup(); + #define EXPHASH(f) (fnv_32_buf((f), sizeof(fsid_t), 0) % exphashsize) static struct exportlisthead *exphead = NULL; static struct exportlisthead *oldexphead = NULL; @@ -1589,7 +1591,7 @@ get_exportlist_one(int passno) anon.cr_groups = anon.cr_smallgrps; anon.cr_uid = UID_NOBODY; anon.cr_ngroups = 1; - anon.cr_groups[0] = GID_NOGROUP; + anon.cr_groups[0] = nogroup(); exflags = MNT_EXPORTED; got_nondir = 0; opt_flags = 0; @@ -3625,7 +3627,7 @@ parsecred(char *namelist, struct expcred *cr) */ cr->cr_groups = cr->cr_smallgrps; cr->cr_uid = UID_NOBODY; - cr->cr_groups[0] = GID_NOGROUP; + cr->cr_groups[0] = nogroup(); cr->cr_ngroups = 1; /* * Get the user's password table entry. @@ -3694,6 +3696,11 @@ parsecred(char *namelist, struct expcred *cr) } groups[cr->cr_ngroups++] = group; } + if (cr->cr_ngroups == 0) { + /* cr->cr_groups[0] filled at start with nogroup(). */ + cr->cr_ngroups = 1; + return; + } if (cr->cr_ngroups > SMALLNGROUPS) cr->cr_groups = malloc(cr->cr_ngroups * sizeof(gid_t)); memcpy(cr->cr_groups, groups, cr->cr_ngroups * sizeof(gid_t)); @@ -4079,3 +4086,19 @@ cp_cred(struct expcred *outcr, struct expcred *incr) memcpy(outcr->cr_groups, incr->cr_groups, incr->cr_ngroups * sizeof(gid_t)); } + +static gid_t +nogroup() +{ + static gid_t nogroup = 0; /* 0 means unset. */ + + if (nogroup == 0) { + const struct group *gr = getgrnam("nogroup"); + + if (gr != NULL && gr->gr_gid != 0) + nogroup = gr->gr_gid; + else + nogroup = GID_NOGROUP; + } + return (nogroup); +}