diff options
| author | Eric Dumazet <edumazet@google.com> | 2025-02-05 15:51:10 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-02-06 16:14:14 -0800 |
| commit | 469308552ca4560176cfc100e7ca84add1bebd7c (patch) | |
| tree | 5cfe694bd89e86f6172b3f836a6a6c2fc009b77c | |
| parent | 482ad2a4ace2740ca0ff1cbc8f3c7f862f3ab507 (diff) | |
ipv4: add RCU protection to ip4_dst_hoplimit()
ip4_dst_hoplimit() must use RCU protection to make
sure the net structure it reads does not disappear.
Fixes: fa50d974d104 ("ipv4: Namespaceify ip_default_ttl sysctl knob")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250205155120.1676781-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | include/net/route.h | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/include/net/route.h b/include/net/route.h index f86775be3e29..c605fd5ec0c0 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -382,10 +382,15 @@ static inline int inet_iif(const struct sk_buff *skb) static inline int ip4_dst_hoplimit(const struct dst_entry *dst) { int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); - struct net *net = dev_net(dst->dev); - if (hoplimit == 0) + if (hoplimit == 0) { + const struct net *net; + + rcu_read_lock(); + net = dev_net_rcu(dst->dev); hoplimit = READ_ONCE(net->ipv4.sysctl_ip_default_ttl); + rcu_read_unlock(); + } return hoplimit; } |