[PATCH 6.1 229/232] ping: Convert hlist_nulls to plain hlist.

Sasha Levin
2026-02-28T18:14:42Z

From: Kuniyuki Iwashima <kuniyu@amazon.com>

[ Upstream commit f1b5dfe63f6a9eb17948cbaee4da4b66f51ac794 ]

Since introduced in commit c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP
socket kind"), ping socket does not use SLAB_TYPESAFE_BY_RCU nor check
nulls marker in loops.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: ad5dfde2a573 ("ping: annotate data-races in ping_lookup()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/ipv4/ping.c | 41 +++++++++++++++--------------------------
1 file changed, 15 insertions(+), 26 deletions(-)

diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index cadf743ab4f52..aae5ad6303a97 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -49,13 +49,8 @@
#include <net/transp_v6.h>
#endif

-#define ping_portaddr_for_each_entry(__sk, node, list) \
- hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
-#define ping_portaddr_for_each_entry_rcu(__sk, node, list) \
- hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
-
struct ping_table {
- struct hlist_nulls_head hash[PING_HTABLE_SIZE];
+ struct hlist_head hash[PING_HTABLE_SIZE];
spinlock_t lock;
};

@@ -74,17 +69,16 @@ static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
}
EXPORT_SYMBOL_GPL(ping_hash);

-static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
- struct net *net, unsigned int num)
+static inline struct hlist_head *ping_hashslot(struct ping_table *table,
+ struct net *net, unsigned int num)
{
return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
}

int ping_get_port(struct sock *sk, unsigned short ident)
{
- struct hlist_nulls_node *node;
- struct hlist_nulls_head *hlist;
struct inet_sock *isk, *isk2;
+ struct hlist_head *hlist;
struct sock *sk2 = NULL;

isk = inet_sk(sk);
@@ -98,7 +92,7 @@ int ping_get_port(struct sock *sk, unsigned short ident)
result++; /* avoid zero */
hlist = ping_hashslot(&ping_table, sock_net(sk),
result);
- ping_portaddr_for_each_entry(sk2, node, hlist) {
+ sk_for_each(sk2, hlist) {
isk2 = inet_sk(sk2);

if (isk2->inet_num == result)
@@ -115,7 +109,7 @@ int ping_get_port(struct sock *sk, unsigned short ident)
goto fail;
} else {
hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
- ping_portaddr_for_each_entry(sk2, node, hlist) {
+ sk_for_each(sk2, hlist) {
isk2 = inet_sk(sk2);

/* BUG? Why is this reuse and not reuseaddr? ping.c
@@ -133,9 +127,8 @@ int ping_get_port(struct sock *sk, unsigned short ident)
isk->inet_num = ident;
if (sk_unhashed(sk)) {
pr_debug("was not hashed\n");
- sock_hold(sk);
+ sk_add_node_rcu(sk, hlist);
sock_set_flag(sk, SOCK_RCU_FREE);
- hlist_nulls_add_head_rcu(&sk->sk_nulls_node, hlist);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
}
spin_unlock(&ping_table.lock);
@@ -161,9 +154,7 @@ void ping_unhash(struct sock *sk)

pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
spin_lock(&ping_table.lock);
- if (sk_hashed(sk)) {
- hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
- sock_put(sk);
+ if (sk_del_node_init_rcu(sk)) {
isk->inet_num = 0;
isk->inet_sport = 0;
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
@@ -175,10 +166,9 @@ EXPORT_SYMBOL_GPL(ping_unhash);
/* Called under rcu_read_lock() */
static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
{
- struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
+ struct hlist_head *hslot = ping_hashslot(&ping_table, net, ident);
struct sock *sk = NULL;
struct inet_sock *isk;
- struct hlist_nulls_node *hnode;
int dif, sdif;

if (skb->protocol == htons(ETH_P_IP)) {
@@ -197,7 +187,7 @@ static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
return NULL;
}

- ping_portaddr_for_each_entry_rcu(sk, hnode, hslot) {
+ sk_for_each_rcu(sk, hslot) {
isk = inet_sk(sk);

pr_debug("iterate\n");
@@ -1043,15 +1033,14 @@ static struct sock *ping_get_first(struct seq_file *seq, int start)

for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
++state->bucket) {
- struct hlist_nulls_node *node;
- struct hlist_nulls_head *hslot;
+ struct hlist_head *hslot;

hslot = &ping_table.hash[state->bucket];

- if (hlist_nulls_empty(hslot))
+ if (hlist_empty(hslot))
continue;

- sk_nulls_for_each(sk, node, hslot) {
+ sk_for_each(sk, hslot) {
if (net_eq(sock_net(sk), net) &&
sk->sk_family == state->family)
goto found;
@@ -1068,7 +1057,7 @@ static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
struct net *net = seq_file_net(seq);

do {
- sk = sk_nulls_next(sk);
+ sk = sk_next(sk);
} while (sk && (!net_eq(sock_net(sk), net)));

if (!sk)
@@ -1204,6 +1193,6 @@ void __init ping_init(void)
int i;

for (i = 0; i < PING_HTABLE_SIZE; i++)
- INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
+ INIT_HLIST_HEAD(&ping_table.hash[i]);
spin_lock_init(&ping_table.lock);
}
--
2.51.0