From: Ido Schimmel idosch@nvidia.com
[ Upstream commit d3f87278bcb80bd7f9519669d928b43320363d4f ]
The kernel does not currently validate that both the minimum and maximum ports of a port range are specified. This can lead user space to think that a filter matching on a port range was successfully added, when in fact it was not. For example, with a patched (buggy) iproute2 that only sends the minimum port, the following commands do not return an error:
# tc filter add dev swp1 ingress pref 1 proto ip flower ip_proto udp src_port 100-200 action pass
# tc filter add dev swp1 ingress pref 1 proto ip flower ip_proto udp dst_port 100-200 action pass
# tc filter show dev swp1 ingress filter protocol ip pref 1 flower chain 0 filter protocol ip pref 1 flower chain 0 handle 0x1 eth_type ipv4 ip_proto udp not_in_hw action order 1: gact action pass random type none pass val 0 index 1 ref 1 bind 1
filter protocol ip pref 1 flower chain 0 handle 0x2 eth_type ipv4 ip_proto udp not_in_hw action order 1: gact action pass random type none pass val 0 index 2 ref 1 bind 1
Fix by returning an error unless both ports are specified:
# tc filter add dev swp1 ingress pref 1 proto ip flower ip_proto udp src_port 100-200 action pass Error: Both min and max source ports must be specified. We have an error talking to the kernel
# tc filter add dev swp1 ingress pref 1 proto ip flower ip_proto udp dst_port 100-200 action pass Error: Both min and max destination ports must be specified. We have an error talking to the kernel
Fixes: 5c72299fba9d ("net: sched: cls_flower: Classify packets using port ranges") Signed-off-by: Ido Schimmel idosch@nvidia.com Reviewed-by: Petr Machata petrm@nvidia.com Acked-by: Jamal Hadi Salim jhs@mojatatu.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/sched/cls_flower.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index ee137d5c20a4f..bff0a5f24aca8 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -784,6 +784,16 @@ static int fl_set_key_port_range(struct nlattr **tb, struct fl_flow_key *key, 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) { + NL_SET_ERR_MSG(extack, + "Both min and max destination ports must be specified"); + return -EINVAL; + } + if (mask->tp_range.tp_min.src != mask->tp_range.tp_max.src) { + NL_SET_ERR_MSG(extack, + "Both min and max source ports must be specified"); + return -EINVAL; + } if (mask->tp_range.tp_min.dst && mask->tp_range.tp_max.dst && ntohs(key->tp_range.tp_max.dst) <= ntohs(key->tp_range.tp_min.dst)) {