4.9-stable review patch. If anyone has any objections, please let me know.
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From: Gao Feng fgao@ikuai8.com
[ Upstream commit 470acf55a021713869b9bcc967268ac90c8a0fac ]
There are two cases which causes refcnt leak.
1. When nf_ct_timeout_ext_add failed in xt_ct_set_timeout, it should free the timeout refcnt. Now goto the err_put_timeout error handler instead of going ahead.
2. When the time policy is not found, we should call module_put. Otherwise, the related cthelper module cannot be removed anymore. It is easy to reproduce by typing the following command: # iptables -t raw -A OUTPUT -p tcp -j CT --helper ftp --timeout xxx
Signed-off-by: Gao Feng fgao@ikuai8.com Signed-off-by: Liping Zhang zlpnobody@gmail.com Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/netfilter/xt_CT.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
--- a/net/netfilter/xt_CT.c +++ b/net/netfilter/xt_CT.c @@ -168,8 +168,10 @@ xt_ct_set_timeout(struct nf_conn *ct, co goto err_put_timeout; } timeout_ext = nf_ct_timeout_ext_add(ct, timeout, GFP_ATOMIC); - if (timeout_ext == NULL) + if (!timeout_ext) { ret = -ENOMEM; + goto err_put_timeout; + }
rcu_read_unlock(); return ret; @@ -201,6 +203,7 @@ static int xt_ct_tg_check(const struct x struct xt_ct_target_info_v1 *info) { struct nf_conntrack_zone zone; + struct nf_conn_help *help; struct nf_conn *ct; int ret = -EOPNOTSUPP;
@@ -249,7 +252,7 @@ static int xt_ct_tg_check(const struct x if (info->timeout[0]) { ret = xt_ct_set_timeout(ct, par, info->timeout); if (ret < 0) - goto err3; + goto err4; } __set_bit(IPS_CONFIRMED_BIT, &ct->status); nf_conntrack_get(&ct->ct_general); @@ -257,6 +260,10 @@ out: info->ct = ct; return 0;
+err4: + help = nfct_help(ct); + if (help) + module_put(help->helper->me); err3: nf_ct_tmpl_free(ct); err2: