[PATCH 5.4 22/37] cls_flower: Fix the behavior using port ranges with hw-offload

From: Yoshiki Komachi komachi.yoshiki@gmail.com

[ Upstream commit 8ffb055beae58574d3e77b4bf9d4d15eace1ca27 ]

The recent commit 5c72299fba9d ("net: sched: cls_flower: Classify packets using port ranges") had added filtering based on port ranges to tc flower. However the commit missed necessary changes in hw-offload code, so the feature gave rise to generating incorrect offloaded flow keys in NIC.

One more detailed example is below:

$ tc qdisc add dev eth0 ingress $ tc filter add dev eth0 ingress protocol ip flower ip_proto tcp \ dst_port 100-200 action drop

With the setup above, an exact match filter with dst_port == 0 will be installed in NIC by hw-offload. IOW, the NIC will have a rule which is equivalent to the following one.

$ tc qdisc add dev eth0 ingress $ tc filter add dev eth0 ingress protocol ip flower ip_proto tcp \ dst_port 0 action drop

The behavior was caused by the flow dissector which extracts packet data into the flow key in the tc flower. More specifically, regardless of exact match or specified port ranges, fl_init_dissector() set the FLOW_DISSECTOR_KEY_PORTS flag in struct flow_dissector to extract port numbers from skb in skb_flow_dissect() called by fl_classify(). Note that device drivers received the same struct flow_dissector object as used in skb_flow_dissect(). Thus, offloaded drivers could not identify which of these is used because the FLOW_DISSECTOR_KEY_PORTS flag was set to struct flow_dissector in either case.

This patch adds the new FLOW_DISSECTOR_KEY_PORTS_RANGE flag and the new tp_range field in struct fl_flow_key to recognize which filters are applied to offloaded drivers. At this point, when filters based on port ranges passed to drivers, drivers return the EOPNOTSUPP error because they do not support the feature (the newly created FLOW_DISSECTOR_KEY_PORTS_RANGE flag).

Fixes: 5c72299fba9d ("net: sched: cls_flower: Classify packets using port ranges") Signed-off-by: Yoshiki Komachi komachi.yoshiki@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/net/flow_dissector.h | 1 net/core/flow_dissector.c | 37 ++++++++++--- net/sched/cls_flower.c | 118 ++++++++++++++++++++++++------------------- 3 files changed, 95 insertions(+), 61 deletions(-)

--- a/include/net/flow_dissector.h +++ b/include/net/flow_dissector.h @@ -229,6 +229,7 @@ enum flow_dissector_key_id { FLOW_DISSECTOR_KEY_IPV4_ADDRS, /* struct flow_dissector_key_ipv4_addrs */ FLOW_DISSECTOR_KEY_IPV6_ADDRS, /* struct flow_dissector_key_ipv6_addrs */ FLOW_DISSECTOR_KEY_PORTS, /* struct flow_dissector_key_ports */ + FLOW_DISSECTOR_KEY_PORTS_RANGE, /* struct flow_dissector_key_ports */ FLOW_DISSECTOR_KEY_ICMP, /* struct flow_dissector_key_icmp */ FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */ FLOW_DISSECTOR_KEY_TIPC, /* struct flow_dissector_key_tipc */ --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -684,6 +684,31 @@ __skb_flow_dissect_tcp(const struct sk_b }

static void +__skb_flow_dissect_ports(const struct sk_buff *skb, + struct flow_dissector *flow_dissector, + void *target_container, void *data, int nhoff, + u8 ip_proto, int hlen) +{ + enum flow_dissector_key_id dissector_ports = FLOW_DISSECTOR_KEY_MAX; + struct flow_dissector_key_ports *key_ports; + + if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS)) + dissector_ports = FLOW_DISSECTOR_KEY_PORTS; + else if (dissector_uses_key(flow_dissector, + FLOW_DISSECTOR_KEY_PORTS_RANGE)) + dissector_ports = FLOW_DISSECTOR_KEY_PORTS_RANGE; + + if (dissector_ports == FLOW_DISSECTOR_KEY_MAX) + return; + + key_ports = skb_flow_dissector_target(flow_dissector, + dissector_ports, + target_container); + key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto, + data, hlen); +} + +static void __skb_flow_dissect_ipv4(const struct sk_buff *skb, struct flow_dissector *flow_dissector, void *target_container, void *data, const struct iphdr *iph) @@ -852,7 +877,6 @@ bool __skb_flow_dissect(const struct net struct flow_dissector_key_control *key_control; struct flow_dissector_key_basic *key_basic; struct flow_dissector_key_addrs *key_addrs; - struct flow_dissector_key_ports *key_ports; struct flow_dissector_key_icmp *key_icmp; struct flow_dissector_key_tags *key_tags; struct flow_dissector_key_vlan *key_vlan; @@ -1300,14 +1324,9 @@ ip_proto_again: break; }

- if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS) && - !(key_control->flags & FLOW_DIS_IS_FRAGMENT)) { - key_ports = skb_flow_dissector_target(flow_dissector, - FLOW_DISSECTOR_KEY_PORTS, - target_container); - key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto, - data, hlen); - } + if (!(key_control->flags & FLOW_DIS_IS_FRAGMENT)) + __skb_flow_dissect_ports(skb, flow_dissector, target_container, + data, nhoff, ip_proto, hlen);

if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ICMP)) { --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -54,8 +54,13 @@ struct fl_flow_key { struct flow_dissector_key_ip ip; struct flow_dissector_key_ip enc_ip; struct flow_dissector_key_enc_opts enc_opts; - struct flow_dissector_key_ports tp_min; - struct flow_dissector_key_ports tp_max; + union { + struct flow_dissector_key_ports tp; + struct { + struct flow_dissector_key_ports tp_min; + struct flow_dissector_key_ports tp_max; + }; + } tp_range; struct flow_dissector_key_ct ct; } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */

@@ -198,19 +203,19 @@ static bool fl_range_port_dst_cmp(struct { __be16 min_mask, max_mask, min_val, max_val;

- min_mask = htons(filter->mask->key.tp_min.dst); - max_mask = htons(filter->mask->key.tp_max.dst); - min_val = htons(filter->key.tp_min.dst); - max_val = htons(filter->key.tp_max.dst); + min_mask = htons(filter->mask->key.tp_range.tp_min.dst); + max_mask = htons(filter->mask->key.tp_range.tp_max.dst); + min_val = htons(filter->key.tp_range.tp_min.dst); + max_val = htons(filter->key.tp_range.tp_max.dst);

if (min_mask && max_mask) { - if (htons(key->tp.dst) < min_val || - htons(key->tp.dst) > max_val) + if (htons(key->tp_range.tp.dst) < min_val || + htons(key->tp_range.tp.dst) > max_val) return false;

/* skb does not have min and max values */ - mkey->tp_min.dst = filter->mkey.tp_min.dst; - mkey->tp_max.dst = filter->mkey.tp_max.dst; + mkey->tp_range.tp_min.dst = filter->mkey.tp_range.tp_min.dst; + mkey->tp_range.tp_max.dst = filter->mkey.tp_range.tp_max.dst; } return true; } @@ -221,19 +226,19 @@ static bool fl_range_port_src_cmp(struct { __be16 min_mask, max_mask, min_val, max_val;

- min_mask = htons(filter->mask->key.tp_min.src); - max_mask = htons(filter->mask->key.tp_max.src); - min_val = htons(filter->key.tp_min.src); - max_val = htons(filter->key.tp_max.src); + min_mask = htons(filter->mask->key.tp_range.tp_min.src); + max_mask = htons(filter->mask->key.tp_range.tp_max.src); + min_val = htons(filter->key.tp_range.tp_min.src); + max_val = htons(filter->key.tp_range.tp_max.src);

if (min_mask && max_mask) { - if (htons(key->tp.src) < min_val || - htons(key->tp.src) > max_val) + if (htons(key->tp_range.tp.src) < min_val || + htons(key->tp_range.tp.src) > max_val) return false;

/* skb does not have min and max values */ - mkey->tp_min.src = filter->mkey.tp_min.src; - mkey->tp_max.src = filter->mkey.tp_max.src; + mkey->tp_range.tp_min.src = filter->mkey.tp_range.tp_min.src; + mkey->tp_range.tp_max.src = filter->mkey.tp_range.tp_max.src; } return true; } @@ -715,23 +720,25 @@ static void fl_set_key_val(struct nlattr static int fl_set_key_port_range(struct nlattr **tb, struct fl_flow_key *key, struct fl_flow_key *mask) { - fl_set_key_val(tb, &key->tp_min.dst, - TCA_FLOWER_KEY_PORT_DST_MIN, &mask->tp_min.dst, - TCA_FLOWER_UNSPEC, sizeof(key->tp_min.dst)); - fl_set_key_val(tb, &key->tp_max.dst, - TCA_FLOWER_KEY_PORT_DST_MAX, &mask->tp_max.dst, - TCA_FLOWER_UNSPEC, sizeof(key->tp_max.dst)); - fl_set_key_val(tb, &key->tp_min.src, - TCA_FLOWER_KEY_PORT_SRC_MIN, &mask->tp_min.src, - TCA_FLOWER_UNSPEC, sizeof(key->tp_min.src)); - fl_set_key_val(tb, &key->tp_max.src, - TCA_FLOWER_KEY_PORT_SRC_MAX, &mask->tp_max.src, - TCA_FLOWER_UNSPEC, sizeof(key->tp_max.src)); - - if ((mask->tp_min.dst && mask->tp_max.dst && - htons(key->tp_max.dst) <= htons(key->tp_min.dst)) || - (mask->tp_min.src && mask->tp_max.src && - htons(key->tp_max.src) <= htons(key->tp_min.src))) + fl_set_key_val(tb, &key->tp_range.tp_min.dst, + TCA_FLOWER_KEY_PORT_DST_MIN, &mask->tp_range.tp_min.dst, + TCA_FLOWER_UNSPEC, sizeof(key->tp_range.tp_min.dst)); + fl_set_key_val(tb, &key->tp_range.tp_max.dst, + TCA_FLOWER_KEY_PORT_DST_MAX, &mask->tp_range.tp_max.dst, + TCA_FLOWER_UNSPEC, sizeof(key->tp_range.tp_max.dst)); + fl_set_key_val(tb, &key->tp_range.tp_min.src, + TCA_FLOWER_KEY_PORT_SRC_MIN, &mask->tp_range.tp_min.src, + TCA_FLOWER_UNSPEC, sizeof(key->tp_range.tp_min.src)); + fl_set_key_val(tb, &key->tp_range.tp_max.src, + TCA_FLOWER_KEY_PORT_SRC_MAX, &mask->tp_range.tp_max.src, + TCA_FLOWER_UNSPEC, sizeof(key->tp_range.tp_max.src)); + + if ((mask->tp_range.tp_min.dst && mask->tp_range.tp_max.dst && + htons(key->tp_range.tp_max.dst) <= + htons(key->tp_range.tp_min.dst)) || + (mask->tp_range.tp_min.src && mask->tp_range.tp_max.src && + htons(key->tp_range.tp_max.src) <= + htons(key->tp_range.tp_min.src))) return -EINVAL;

return 0; @@ -1320,9 +1327,10 @@ static void fl_init_dissector(struct flo FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4); FL_KEY_SET_IF_MASKED(mask, keys, cnt, FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6); - if (FL_KEY_IS_MASKED(mask, tp) || - FL_KEY_IS_MASKED(mask, tp_min) || FL_KEY_IS_MASKED(mask, tp_max)) - FL_KEY_SET(keys, cnt, FLOW_DISSECTOR_KEY_PORTS, tp); + FL_KEY_SET_IF_MASKED(mask, keys, cnt, + FLOW_DISSECTOR_KEY_PORTS, tp); + FL_KEY_SET_IF_MASKED(mask, keys, cnt, + FLOW_DISSECTOR_KEY_PORTS_RANGE, tp_range); FL_KEY_SET_IF_MASKED(mask, keys, cnt, FLOW_DISSECTOR_KEY_IP, ip); FL_KEY_SET_IF_MASKED(mask, keys, cnt, @@ -1371,8 +1379,10 @@ static struct fl_flow_mask *fl_create_ne

fl_mask_copy(newmask, mask);

- if ((newmask->key.tp_min.dst && newmask->key.tp_max.dst) || - (newmask->key.tp_min.src && newmask->key.tp_max.src)) + if ((newmask->key.tp_range.tp_min.dst && + newmask->key.tp_range.tp_max.dst) || + (newmask->key.tp_range.tp_min.src && + newmask->key.tp_range.tp_max.src)) newmask->flags |= TCA_FLOWER_MASK_FLAGS_RANGE;

err = fl_init_mask_hashtable(newmask); @@ -1970,18 +1980,22 @@ static int fl_dump_key_val(struct sk_buf static int fl_dump_key_port_range(struct sk_buff *skb, struct fl_flow_key *key, struct fl_flow_key *mask) { - if (fl_dump_key_val(skb, &key->tp_min.dst, TCA_FLOWER_KEY_PORT_DST_MIN, - &mask->tp_min.dst, TCA_FLOWER_UNSPEC, - sizeof(key->tp_min.dst)) || - fl_dump_key_val(skb, &key->tp_max.dst, TCA_FLOWER_KEY_PORT_DST_MAX, - &mask->tp_max.dst, TCA_FLOWER_UNSPEC, - sizeof(key->tp_max.dst)) || - fl_dump_key_val(skb, &key->tp_min.src, TCA_FLOWER_KEY_PORT_SRC_MIN, - &mask->tp_min.src, TCA_FLOWER_UNSPEC, - sizeof(key->tp_min.src)) || - fl_dump_key_val(skb, &key->tp_max.src, TCA_FLOWER_KEY_PORT_SRC_MAX, - &mask->tp_max.src, TCA_FLOWER_UNSPEC, - sizeof(key->tp_max.src))) + if (fl_dump_key_val(skb, &key->tp_range.tp_min.dst, + TCA_FLOWER_KEY_PORT_DST_MIN, + &mask->tp_range.tp_min.dst, TCA_FLOWER_UNSPEC, + sizeof(key->tp_range.tp_min.dst)) || + fl_dump_key_val(skb, &key->tp_range.tp_max.dst, + TCA_FLOWER_KEY_PORT_DST_MAX, + &mask->tp_range.tp_max.dst, TCA_FLOWER_UNSPEC, + sizeof(key->tp_range.tp_max.dst)) || + fl_dump_key_val(skb, &key->tp_range.tp_min.src, + TCA_FLOWER_KEY_PORT_SRC_MIN, + &mask->tp_range.tp_min.src, TCA_FLOWER_UNSPEC, + sizeof(key->tp_range.tp_min.src)) || + fl_dump_key_val(skb, &key->tp_range.tp_max.src, + TCA_FLOWER_KEY_PORT_SRC_MAX, + &mask->tp_range.tp_max.src, TCA_FLOWER_UNSPEC, + sizeof(key->tp_range.tp_max.src))) return -1;

return 0;