diff options
Diffstat (limited to 'net/netfilter')
| -rw-r--r-- | net/netfilter/nft_socket.c | 41 |
1 files changed, 38 insertions, 3 deletions
diff --git a/net/netfilter/nft_socket.c b/net/netfilter/nft_socket.c index 765ffd6e06bc..12cdff640492 100644 --- a/net/netfilter/nft_socket.c +++ b/net/netfilter/nft_socket.c @@ -9,7 +9,8 @@ struct nft_socket { enum nft_socket_keys key:8; - u8 level; + u8 level; /* cgroupv2 level to extract */ + u8 level_user; /* cgroupv2 level provided by userspace */ u8 len; union { u8 dreg; @@ -53,6 +54,28 @@ nft_sock_get_eval_cgroupv2(u32 *dest, struct sock *sk, const struct nft_pktinfo memcpy(dest, &cgid, sizeof(u64)); return true; } + +/* process context only, uses current->nsproxy. */ +static noinline int nft_socket_cgroup_subtree_level(void) +{ + struct cgroup *cgrp = cgroup_get_from_path("/"); + int level; + + if (!cgrp) + return -ENOENT; + + level = cgrp->level; + + cgroup_put(cgrp); + + if (WARN_ON_ONCE(level > 255)) + return -ERANGE; + + if (WARN_ON_ONCE(level < 0)) + return -EINVAL; + + return level; +} #endif static struct sock *nft_socket_do_lookup(const struct nft_pktinfo *pkt) @@ -174,9 +197,10 @@ static int nft_socket_init(const struct nft_ctx *ctx, case NFT_SOCKET_MARK: len = sizeof(u32); break; -#ifdef CONFIG_CGROUPS +#ifdef CONFIG_SOCK_CGROUP_DATA case NFT_SOCKET_CGROUPV2: { unsigned int level; + int err; if (!tb[NFTA_SOCKET_LEVEL]) return -EINVAL; @@ -185,6 +209,17 @@ static int nft_socket_init(const struct nft_ctx *ctx, if (level > 255) return -EOPNOTSUPP; + err = nft_socket_cgroup_subtree_level(); + if (err < 0) + return err; + + priv->level_user = level; + + level += err; + /* Implies a giant cgroup tree */ + if (WARN_ON_ONCE(level > 255)) + return -EOPNOTSUPP; + priv->level = level; len = sizeof(u64); break; @@ -209,7 +244,7 @@ static int nft_socket_dump(struct sk_buff *skb, if (nft_dump_register(skb, NFTA_SOCKET_DREG, priv->dreg)) return -1; if (priv->key == NFT_SOCKET_CGROUPV2 && - nla_put_be32(skb, NFTA_SOCKET_LEVEL, htonl(priv->level))) + nla_put_be32(skb, NFTA_SOCKET_LEVEL, htonl(priv->level_user))) return -1; return 0; } |