Commit 8281b7ec authored by Kuniyuki Iwashima's avatar Kuniyuki Iwashima Committed by David S. Miller
Browse files

ip: Fix data-races around sysctl_ip_default_ttl. 



While reading sysctl_ip_default_ttl, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent db886979

drivers/net/ethernet/netronome/nfp/flower/action.c

+1 −1
Original line number Diff line number Diff line
@@ -474,7 +474,7 @@ nfp_fl_set_tun(struct nfp_app *app, struct nfp_fl_set_tun *set_tun, 
			set_tun->ttl = ip4_dst_hoplimit(&rt->dst);

			ip_rt_put(rt);

		} else {

			set_tun->ttl = net->ipv4.sysctl_ip_default_ttl;

			set_tun->ttl = READ_ONCE(net->ipv4.sysctl_ip_default_ttl);

		}

	}

include/net/route.h

+1 −1
Original line number Diff line number Diff line
@@ -373,7 +373,7 @@ static inline int ip4_dst_hoplimit(const struct dst_entry *dst) 
	struct net *net = dev_net(dst->dev);



	if (hoplimit == 0)

		hoplimit = net->ipv4.sysctl_ip_default_ttl;

		hoplimit = READ_ONCE(net->ipv4.sysctl_ip_default_ttl);

	return hoplimit;

}

net/ipv4/ip_sockglue.c

+1 −1
Original line number Diff line number Diff line
@@ -1606,7 +1606,7 @@ static int do_ip_getsockopt(struct sock *sk, int level, int optname, 
	{

		struct net *net = sock_net(sk);

		val = (inet->uc_ttl == -1 ?

		       net->ipv4.sysctl_ip_default_ttl :

		       READ_ONCE(net->ipv4.sysctl_ip_default_ttl) :

		       inet->uc_ttl);

		break;

	}

net/ipv4/netfilter/nf_reject_ipv4.c

+2 −2
Original line number Diff line number Diff line
@@ -62,7 +62,7 @@ struct sk_buff *nf_reject_skb_v4_tcp_reset(struct net *net, 


	skb_reserve(nskb, LL_MAX_HEADER);

	niph = nf_reject_iphdr_put(nskb, oldskb, IPPROTO_TCP,

				   net->ipv4.sysctl_ip_default_ttl);

				   READ_ONCE(net->ipv4.sysctl_ip_default_ttl));

	nf_reject_ip_tcphdr_put(nskb, oldskb, oth);

	niph->tot_len = htons(nskb->len);

	ip_send_check(niph);
@@ -117,7 +117,7 @@ struct sk_buff *nf_reject_skb_v4_unreach(struct net *net, 


	skb_reserve(nskb, LL_MAX_HEADER);

	niph = nf_reject_iphdr_put(nskb, oldskb, IPPROTO_ICMP,

				   net->ipv4.sysctl_ip_default_ttl);

				   READ_ONCE(net->ipv4.sysctl_ip_default_ttl));



	skb_reset_transport_header(nskb);

	icmph = skb_put_zero(nskb, sizeof(struct icmphdr));

net/ipv4/proc.c

+1 −1
Original line number Diff line number Diff line
@@ -387,7 +387,7 @@ static int snmp_seq_show_ipstats(struct seq_file *seq, void *v) 


	seq_printf(seq, "\nIp: %d %d",

		   IPV4_DEVCONF_ALL(net, FORWARDING) ? 1 : 2,

		   net->ipv4.sysctl_ip_default_ttl);

		   READ_ONCE(net->ipv4.sysctl_ip_default_ttl));



	BUILD_BUG_ON(offsetof(struct ipstats_mib, mibs) != 0);

	snmp_get_cpu_field64_batch(buff64, snmp4_ipstats_list,