diff options
| author |   Lukasz Pawelczyk <l.pawelczyk@samsung.com> | 2019-05-10 13:46:22 +0200 |
|---|---|---|
| committer |   Pablo Neira Ayuso <pablo@netfilter.org> | 2019-05-31 18:02:41 +0200 |
| commit | ea6cc2fd8a2b89ab6dcd096ba6dbc1ecbdf26564 (patch) | |
| tree | 5cc3928e493b7af80fdb71a114c55301630e44dd /net | |
| parent | ipvs: strip udp tunnel headers from icmp errors (diff) | |
| download | linux-dev-ea6cc2fd8a2b89ab6dcd096ba6dbc1ecbdf26564.tar.xz linux-dev-ea6cc2fd8a2b89ab6dcd096ba6dbc1ecbdf26564.zip | |
netfilter: xt_owner: Add supplementary groups option
The XT_OWNER_SUPPL_GROUPS flag causes GIDs specified with XT_OWNER_GID
to be also checked in the supplementary groups of a process.
f_cred->group_info cannot be modified during its lifetime and f_cred
holds a reference to it so it's safe to use.
Signed-off-by: Lukasz Pawelczyk <l.pawelczyk@samsung.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/xt_owner.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/net/netfilter/xt_owner.c b/net/netfilter/xt_owner.c index 46686fb73784..a8784502aca6 100644 --- a/net/netfilter/xt_owner.c +++ b/net/netfilter/xt_owner.c @@ -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; } |