ipv4: Initialize flowi4_multipath_hash in data path
authorDavid Ahern <dsahern@gmail.com>
Sun, 13 Sep 2020 18:43:39 +0000 (12:43 -0600)
committerDavid S. Miller <davem@davemloft.net>
Mon, 14 Sep 2020 21:54:56 +0000 (14:54 -0700)
flowi4_multipath_hash was added by the commit referenced below for
tunnels. Unfortunately, the patch did not initialize the new field
for several fast path lookups that do not initialize the entire flow
struct to 0. Fix those locations. Currently, flowi4_multipath_hash
is random garbage and affects the hash value computed by
fib_multipath_hash for multipath selection.

Fixes: 24ba14406c5c ("route: Add multipath_hash in flowi_common to make user-define hash")
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: wenxu <wenxu@ucloud.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/net/flow.h
net/core/filter.c
net/ipv4/fib_frontend.c
net/ipv4/route.c

index 929d3ca..b2531df 100644 (file)
@@ -116,6 +116,7 @@ static inline void flowi4_init_output(struct flowi4 *fl4, int oif,
        fl4->saddr = saddr;
        fl4->fl4_dport = dport;
        fl4->fl4_sport = sport;
+       fl4->flowi4_multipath_hash = 0;
 }
 
 /* Reset some input parameters after previous lookup */
index 1f647ab..1b16837 100644 (file)
@@ -4838,6 +4838,7 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
        fl4.saddr = params->ipv4_src;
        fl4.fl4_sport = params->sport;
        fl4.fl4_dport = params->dport;
+       fl4.flowi4_multipath_hash = 0;
 
        if (flags & BPF_FIB_LOOKUP_DIRECT) {
                u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
index 4107949..86a23e4 100644 (file)
@@ -362,6 +362,7 @@ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
        fl4.flowi4_tun_key.tun_id = 0;
        fl4.flowi4_flags = 0;
        fl4.flowi4_uid = sock_net_uid(net, NULL);
+       fl4.flowi4_multipath_hash = 0;
 
        no_addr = idev->ifa_list == NULL;
 
index 8ca6bca..e5f210d 100644 (file)
@@ -2147,6 +2147,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
        fl4.daddr = daddr;
        fl4.saddr = saddr;
        fl4.flowi4_uid = sock_net_uid(net, NULL);
+       fl4.flowi4_multipath_hash = 0;
 
        if (fib4_rules_early_flow_dissect(net, skb, &fl4, &_flkeys)) {
                flkeys = &_flkeys;