Add fixed patch

root/target/linux/generic/pending-5.4/645-netfilter-nf_flow_table-rework-hardware-offload-time.patch

@@ -0,0 +1,26 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Sun, 25 Mar 2018 21:10:55 +0200
+Subject: [PATCH] netfilter: nf_flow_table: rework hardware offload timeout
+ handling
+
+Some offload implementations send keepalive packets + explicit
+notifications of TCP FIN/RST packets. In this case it is more convenient
+to simply let the driver update flow->timeout handling and use the
+regular flow offload gc step.
+
+For drivers that manage their own lifetime, a separate flag can be set
+to avoid gc timeouts.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/include/net/netfilter/nf_flow_table.h
++++ b/include/net/netfilter/nf_flow_table.h
+@@ -75,6 +75,7 @@ struct flow_offload_tuple_rhash {
+ #define FLOW_OFFLOAD_DYING	0x4
+ #define FLOW_OFFLOAD_TEARDOWN	0x8
+ #define FLOW_OFFLOAD_HW		0x10
++#define FLOW_OFFLOAD_KEEP	0x20
+ 
+ struct flow_offload {
+ 	struct flow_offload_tuple_rhash		tuplehash[FLOW_OFFLOAD_DIR_MAX];