From 66b0f688a49a62497e6ad21ddbe675a45c0d8ada Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Mon, 22 Feb 2021 11:00:34 +0800 Subject: [PATCH] netfilter: conntrack: fix reading nf_conntrack_buckets stable inclusion from linux-4.19.169 commit b69a79c62c7055a7c36464092b45b25018958153 -------------------------------- commit f6351c3f1c27c80535d76cac2299aec44c36291e upstream. The old way of changing the conntrack hashsize runtime was through changing the module param via file /sys/module/nf_conntrack/parameters/hashsize. This was extended to sysctl change in commit 3183ab8997a4 ("netfilter: conntrack: allow increasing bucket size via sysctl too"). The commit introduced second "user" variable nf_conntrack_htable_size_user which shadow actual variable nf_conntrack_htable_size. When hashsize is changed via module param this "user" variable isn't updated. This results in sysctl net/netfilter/nf_conntrack_buckets shows the wrong value when users update via the old way. This patch fix the issue by always updating "user" variable when reading the proc file. This will take care of changes to the actual variable without sysctl need to be aware. Fixes: 3183ab8997a4 ("netfilter: conntrack: allow increasing bucket size via sysctl too") Reported-by: Yoel Caspersen Signed-off-by: Jesper Dangaard Brouer Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yang Yingliang Signed-off-by: Cheng Jian --- net/netfilter/nf_conntrack_standalone.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c index 4c94f3ba2ae4..dcd8e7922951 100644 --- a/net/netfilter/nf_conntrack_standalone.c +++ b/net/netfilter/nf_conntrack_standalone.c @@ -500,6 +500,9 @@ nf_conntrack_hash_sysctl(struct ctl_table *table, int write, { int ret; + /* module_param hashsize could have changed value */ + nf_conntrack_htable_size_user = nf_conntrack_htable_size; + ret = proc_dointvec(table, write, buffer, lenp, ppos); if (ret < 0 || !write) return ret; -- GitLab