diff options
Diffstat (limited to 'net/netfilter/xt_owner.c')
| -rw-r--r-- | net/netfilter/xt_owner.c | 31 |
1 files changed, 24 insertions, 7 deletions
diff --git a/net/netfilter/xt_owner.c b/net/netfilter/xt_owner.c index 46686fb73784..e85ce69924ae 100644 --- a/net/netfilter/xt_owner.c +++ b/net/netfilter/xt_owner.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Kernel module to match various things tied to sockets associated with * locally generated outgoing packets. @@ -5,10 +6,6 @@ * (C) 2000 Marc Boucher <marc@mbsi.ca> * * Copyright © CC Computer Consultants GmbH, 2007 - 2008 - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. */ #include <linux/module.h> #include <linux/skbuff.h> @@ -25,6 +22,9 @@ static int owner_check(const struct xt_mtchk_param *par) struct xt_owner_match_info *info = par->matchinfo; struct net *net = par->net; + if (info->match & ~XT_OWNER_MASK) + return -EINVAL; + /* Only allow the common case where the userns of the writer * matches the userns of the network namespace. */ @@ -91,11 +91,28 @@ owner_mt(const struct sk_buff *skb, struct xt_action_param *par) } if (info->match & XT_OWNER_GID) { + unsigned int i, match = false; kgid_t gid_min = make_kgid(net->user_ns, info->gid_min); kgid_t gid_max = make_kgid(net->user_ns, info->gid_max); - if ((gid_gte(filp->f_cred->fsgid, gid_min) && - gid_lte(filp->f_cred->fsgid, gid_max)) ^ - !(info->invert & XT_OWNER_GID)) + struct group_info *gi = filp->f_cred->group_info; + + if (gid_gte(filp->f_cred->fsgid, gid_min) && + gid_lte(filp->f_cred->fsgid, gid_max)) + match = true; + + if (!match && (info->match & XT_OWNER_SUPPL_GROUPS) && gi) { + for (i = 0; i < gi->ngroups; ++i) { + kgid_t group = gi->gid[i]; + + if (gid_gte(group, gid_min) && + gid_lte(group, gid_max)) { + match = true; + break; + } + } + } + + if (match ^ !(info->invert & XT_OWNER_GID)) return false; } |