ipv4: convert fib_num_tclassid_users to atomic_t

Before commit faa041a40b ("ipv4: Create cleanup helper for fib_nh")
changes to net->ipv4.fib_num_tclassid_users were protected by RTNL.

After the change, this is no longer the case, as free_fib_info_rcu()
runs after rcu grace period, without rtnl being held.

Fixes: faa041a40b ("ipv4: Create cleanup helper for fib_nh")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsahern@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2021-12-01 18:26:35 -08:00 committed by David S. Miller
parent a37a0ee4d2
commit 213f5f8f31
5 changed files with 7 additions and 7 deletions

View File

@ -438,7 +438,7 @@ int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
#ifdef CONFIG_IP_ROUTE_CLASSID
static inline int fib_num_tclassid_users(struct net *net)
{
return net->ipv4.fib_num_tclassid_users;
return atomic_read(&net->ipv4.fib_num_tclassid_users);
}
#else
static inline int fib_num_tclassid_users(struct net *net)

View File

@ -65,7 +65,7 @@ struct netns_ipv4 {
bool fib_has_custom_local_routes;
bool fib_offload_disabled;
#ifdef CONFIG_IP_ROUTE_CLASSID
int fib_num_tclassid_users;
atomic_t fib_num_tclassid_users;
#endif
struct hlist_head *fib_table_hash;
struct sock *fibnl;

View File

@ -1582,7 +1582,7 @@ static int __net_init fib_net_init(struct net *net)
int error;
#ifdef CONFIG_IP_ROUTE_CLASSID
net->ipv4.fib_num_tclassid_users = 0;
atomic_set(&net->ipv4.fib_num_tclassid_users, 0);
#endif
error = ip_fib_net_init(net);
if (error < 0)

View File

@ -264,7 +264,7 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
if (tb[FRA_FLOW]) {
rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
if (rule4->tclassid)
net->ipv4.fib_num_tclassid_users++;
atomic_inc(&net->ipv4.fib_num_tclassid_users);
}
#endif
@ -296,7 +296,7 @@ static int fib4_rule_delete(struct fib_rule *rule)
#ifdef CONFIG_IP_ROUTE_CLASSID
if (((struct fib4_rule *)rule)->tclassid)
net->ipv4.fib_num_tclassid_users--;
atomic_dec(&net->ipv4.fib_num_tclassid_users);
#endif
net->ipv4.fib_has_custom_rules = true;

View File

@ -220,7 +220,7 @@ void fib_nh_release(struct net *net, struct fib_nh *fib_nh)
{
#ifdef CONFIG_IP_ROUTE_CLASSID
if (fib_nh->nh_tclassid)
net->ipv4.fib_num_tclassid_users--;
atomic_dec(&net->ipv4.fib_num_tclassid_users);
#endif
fib_nh_common_release(&fib_nh->nh_common);
}
@ -632,7 +632,7 @@ int fib_nh_init(struct net *net, struct fib_nh *nh,
#ifdef CONFIG_IP_ROUTE_CLASSID
nh->nh_tclassid = cfg->fc_flow;
if (nh->nh_tclassid)
net->ipv4.fib_num_tclassid_users++;
atomic_inc(&net->ipv4.fib_num_tclassid_users);
#endif
#ifdef CONFIG_IP_ROUTE_MULTIPATH
nh->fib_nh_weight = nh_weight;