diff options
| author | Florian Westphal <fw@strlen.de> | 2023-02-20 17:24:00 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2023-02-22 00:28:47 +0100 |
| commit | fdf6491193e411087ae77bcbc6468e3e1cff99ed (patch) | |
| tree | fcf73502b337cbfe507b4c8480515fb30e82d6e2 /include | |
| parent | netfilter: xt_length: use skb len to match in length_mt6 (diff) | |
| download | linux-fdf6491193e411087ae77bcbc6468e3e1cff99ed.tar.xz linux-fdf6491193e411087ae77bcbc6468e3e1cff99ed.zip | |
netfilter: ctnetlink: make event listener tracking global
pernet tracking doesn't work correctly because other netns might have
set NETLINK_LISTEN_ALL_NSID on its event socket.
In this case its expected that events originating in other net
namespaces are also received.
Making pernet-tracking work while also honoring NETLINK_LISTEN_ALL_NSID
requires much more intrusive changes both in netlink and nfnetlink,
f.e. adding a 'setsockopt' callback that lets nfnetlink know that the
event socket entered (or left) ALL_NSID mode.
Move to global tracking instead: if there is an event socket anywhere
on the system, all net namespaces which have conntrack enabled and
use autobind mode will allocate the ecache extension.
netlink_has_listeners() returns false only if the given group has no
subscribers in any net namespace, the 'net' argument passed to
nfnetlink_has_listeners is only used to derive the protocol (nfnetlink),
it has no other effect.
For proper NETLINK_LISTEN_ALL_NSID-aware pernet tracking of event
listeners a new netlink_has_net_listeners() is also needed.
Fixes: 90d1daa45849 ("netfilter: conntrack: add nf_conntrack_events autodetect mode")
Reported-by: Bryce Kahle <bryce.kahle@datadoghq.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/netfilter.h | 5 | ||||
| -rw-r--r-- | include/net/netns/conntrack.h | 1 |
2 files changed, 5 insertions, 1 deletions
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index d8817d381c14..bef8db9d6c08 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -488,4 +488,9 @@ extern const struct nfnl_ct_hook __rcu *nfnl_ct_hook; */ DECLARE_PER_CPU(bool, nf_skb_duplicated); +/** + * Contains bitmask of ctnetlink event subscribers, if any. + * Can't be pernet due to NETLINK_LISTEN_ALL_NSID setsockopt flag. + */ +extern u8 nf_ctnetlink_has_listener; #endif /*__LINUX_NETFILTER_H*/ diff --git a/include/net/netns/conntrack.h b/include/net/netns/conntrack.h index e1290c159184..1f463b3957c7 100644 --- a/include/net/netns/conntrack.h +++ b/include/net/netns/conntrack.h @@ -95,7 +95,6 @@ struct nf_ip_net { struct netns_ct { #ifdef CONFIG_NF_CONNTRACK_EVENTS - u8 ctnetlink_has_listener; bool ecache_dwork_pending; #endif u8 sysctl_log_invalid; /* Log invalid packets */ |