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| author |   Xin Long <lucien.xin@gmail.com> | 2018-02-16 18:04:56 +0800 |
|---|---|---|
| committer |   Pablo Neira Ayuso <pablo@netfilter.org> | 2018-03-05 23:15:43 +0100 |
| commit | f31e5f1a891f989f107e8caa6b49dd4df0e12265 (patch) | |
| tree | 100f02b6a29e79f58e0b6ffa415b5f0e4d1647b4 /net/ipv4/netfilter/ip_tables.c | |
| parent | netfilter: ipt_ah: return boolean instead of integer (diff) | |
| download | wireguard-linux-f31e5f1a891f989f107e8caa6b49dd4df0e12265.tar.xz wireguard-linux-f31e5f1a891f989f107e8caa6b49dd4df0e12265.zip | |
netfilter: unlock xt_table earlier in __do_replace
Now it's doing cleanup_entry for oldinfo under the xt_table lock,
but it's not really necessary. After the replacement job is done
in xt_replace_table, oldinfo is not used elsewhere any more, and
it can be freed without xt_table lock safely.
The important thing is that rtnl_lock is called in some xt_target
destroy, which means rtnl_lock, a big lock is used in xt_table
lock, a smaller one. It usually could be the reason why a dead
lock may happen.
Besides, all xt_target/match checkentry is called out of xt_table
lock. It's better also to move all cleanup_entry calling out of
xt_table lock, just as do_replace_finish does for ebtables.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/ipv4/netfilter/ip_tables.c')
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index d4f7584d2dbe..4f7153e25e0b 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1087,6 +1087,8 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, (newinfo->number <= oldinfo->initial_entries)) module_put(t->me); + xt_table_unlock(t); + get_old_counters(oldinfo, counters); /* Decrease module usage counts and free resource */ @@ -1100,7 +1102,6 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, net_warn_ratelimited("iptables: counters copy to user failed while replacing table\n"); } vfree(counters); - xt_table_unlock(t); return ret; put_module: |