net/sched: cls_flower: Reject invalid ct_state flags rules

Reject the unsupported and invalid ct_state flags of cls flower rules.

Fixes: e0ace68af2ac ("net/sched: cls_flower: Add matching on conntrack info")
Signed-off-by: wenxu <wenxu@ucloud.cn>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index ee95f42fb0ecfab10c641c7b4401ea14152ada32..88f4bf0047e7abae7facd325c6a67d5db4d37d56 100644 (file)
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -591,6 +591,8 @@ enum {
        TCA_FLOWER_KEY_CT_FLAGS_ESTABLISHED = 1 << 1, /* Part of an existing connection. */
        TCA_FLOWER_KEY_CT_FLAGS_RELATED = 1 << 2, /* Related to an established connection. */
        TCA_FLOWER_KEY_CT_FLAGS_TRACKED = 1 << 3, /* Conntrack has occurred. */
+
+       __TCA_FLOWER_KEY_CT_FLAGS_MAX,
 };
 
 enum {

diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 84f932532db7dc39e23d946cd73e97ba042795a4..46c1b3e9f66a575a28593d87f2d4a901b930fd4d 100644 (file)
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -30,6 +30,11 @@
 
 #include <uapi/linux/netfilter/nf_conntrack_common.h>
 
+#define TCA_FLOWER_KEY_CT_FLAGS_MAX \
+               ((__TCA_FLOWER_KEY_CT_FLAGS_MAX - 1) << 1)
+#define TCA_FLOWER_KEY_CT_FLAGS_MASK \
+               (TCA_FLOWER_KEY_CT_FLAGS_MAX - 1)
+
 struct fl_flow_key {
        struct flow_dissector_key_meta meta;
        struct flow_dissector_key_control control;
@@ -686,8 +691,10 @@ static const struct nla_policy fl_policy[TCA_FLOWER_MAX + 1] = {
        [TCA_FLOWER_KEY_ENC_IP_TTL_MASK] = { .type = NLA_U8 },
        [TCA_FLOWER_KEY_ENC_OPTS]       = { .type = NLA_NESTED },
        [TCA_FLOWER_KEY_ENC_OPTS_MASK]  = { .type = NLA_NESTED },
-       [TCA_FLOWER_KEY_CT_STATE]       = { .type = NLA_U16 },
-       [TCA_FLOWER_KEY_CT_STATE_MASK]  = { .type = NLA_U16 },
+       [TCA_FLOWER_KEY_CT_STATE]       =
+               NLA_POLICY_MASK(NLA_U16, TCA_FLOWER_KEY_CT_FLAGS_MASK),
+       [TCA_FLOWER_KEY_CT_STATE_MASK]  =
+               NLA_POLICY_MASK(NLA_U16, TCA_FLOWER_KEY_CT_FLAGS_MASK),
        [TCA_FLOWER_KEY_CT_ZONE]        = { .type = NLA_U16 },
        [TCA_FLOWER_KEY_CT_ZONE_MASK]   = { .type = NLA_U16 },
        [TCA_FLOWER_KEY_CT_MARK]        = { .type = NLA_U32 },
@@ -1390,12 +1397,33 @@ static int fl_set_enc_opt(struct nlattr **tb, struct fl_flow_key *key,
        return 0;
 }
 
+static int fl_validate_ct_state(u16 state, struct nlattr *tb,
+                               struct netlink_ext_ack *extack)
+{
+       if (state && !(state & TCA_FLOWER_KEY_CT_FLAGS_TRACKED)) {
+               NL_SET_ERR_MSG_ATTR(extack, tb,
+                                   "no trk, so no other flag can be set");
+               return -EINVAL;
+       }
+
+       if (state & TCA_FLOWER_KEY_CT_FLAGS_NEW &&
+           state & TCA_FLOWER_KEY_CT_FLAGS_ESTABLISHED) {
+               NL_SET_ERR_MSG_ATTR(extack, tb,
+                                   "new and est are mutually exclusive");
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
 static int fl_set_key_ct(struct nlattr **tb,
                         struct flow_dissector_key_ct *key,
                         struct flow_dissector_key_ct *mask,
                         struct netlink_ext_ack *extack)
 {
        if (tb[TCA_FLOWER_KEY_CT_STATE]) {
+               int err;
+
                if (!IS_ENABLED(CONFIG_NF_CONNTRACK)) {
                        NL_SET_ERR_MSG(extack, "Conntrack isn't enabled");
                        return -EOPNOTSUPP;
@@ -1403,6 +1431,13 @@ static int fl_set_key_ct(struct nlattr **tb,
                fl_set_key_val(tb, &key->ct_state, TCA_FLOWER_KEY_CT_STATE,
                               &mask->ct_state, TCA_FLOWER_KEY_CT_STATE_MASK,
                               sizeof(key->ct_state));
+
+               err = fl_validate_ct_state(mask->ct_state,
+                                          tb[TCA_FLOWER_KEY_CT_STATE_MASK],
+                                          extack);
+               if (err)
+                       return err;
+
        }
        if (tb[TCA_FLOWER_KEY_CT_ZONE]) {
                if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {