Re: [PATCH net-next 4/4] inetpeer: do not get a refcount in inet_getpeer()
From: Ido Schimmel <hidden>
Date: 2024-12-15 15:48:56
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
On Fri, Dec 13, 2024 at 01:02:12PM +0000, Eric Dumazet wrote:
quoted hunk ↗ jump to hunk
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 5eeb9f569a706cf2766d74bcf1a667c8930804f2..7a1b1af2edcae0b0648ef3c3411b4ef36e6d9b14 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c@@ -322,11 +322,11 @@ static bool icmpv4_xrlim_allow(struct net *net, struct rtable *rt, goto out; vif = l3mdev_master_ifindex(dst->dev); + rcu_read_lock(); peer = inet_getpeer_v4(net->ipv4.peers, fl4->daddr, vif); rc = inet_peer_xrlim_allow(peer, READ_ONCE(net->ipv4.sysctl_icmp_ratelimit)); - if (peer) - inet_putpeer(peer); + rcu_read_unlock(); out: if (!rc) __ICMP_INC_STATS(net, ICMP_MIB_RATELIMITHOST);
Maybe convert l3mdev_master_ifindex() to l3mdev_master_ifindex_rcu() and move it into the RCU critical section?
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 7a1b1af2edca..094084b61bff 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c@@ -312,7 +312,6 @@ static bool icmpv4_xrlim_allow(struct net *net, struct rtable *rt, struct dst_entry *dst = &rt->dst; struct inet_peer *peer; bool rc = true; - int vif; if (!apply_ratelimit) return true;
@@ -321,9 +320,9 @@ static bool icmpv4_xrlim_allow(struct net *net, struct rtable *rt, if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) goto out; - vif = l3mdev_master_ifindex(dst->dev); rcu_read_lock(); - peer = inet_getpeer_v4(net->ipv4.peers, fl4->daddr, vif); + peer = inet_getpeer_v4(net->ipv4.peers, fl4->daddr, + l3mdev_master_ifindex_rcu(dst->dev)); rc = inet_peer_xrlim_allow(peer, READ_ONCE(net->ipv4.sysctl_icmp_ratelimit)); rcu_read_unlock();
[...]
quoted hunk ↗ jump to hunk
@@ -975,9 +975,9 @@ static int ip_error(struct sk_buff *skb) break; } + rcu_read_lock(); peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, l3mdev_master_ifindex(skb->dev)); - send = true; if (peer) { now = jiffies;
And here?
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index d2086648dcf1..9f9d4e6ea1b9 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c@@ -977,7 +977,7 @@ static int ip_error(struct sk_buff *skb) rcu_read_lock(); peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, - l3mdev_master_ifindex(skb->dev)); + l3mdev_master_ifindex_rcu(skb->dev)); send = true; if (peer) { now = jiffies;