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;
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)
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;
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;
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;
}