On Tue, Mar 21, 2017 at 08:22:29AM +0800, f...@ikuai8.com wrote:
> From: Gao Feng <f...@ikuai8.com>
>
> In the commit 93557f53e1fb ("netfilter: nf_conntrack: nf_conntrack snmp
> helper"), the snmp_helper is replaced by nf_nat_snmp_hook. So the
> snmp_helper is never registered. But it still tries to unregister the
> snmp_helper, it could cause the panic.
>
> Now remove the useless snmp_helper and the unregister call in the
> error handler.
>
> Fixes: 93557f53e1fb ("netfilter: nf_conntrack: nf_conntrack snmp helper")
>
> Signed-off-by: Gao Feng <f...@ikuai8.com>
> ---
> v3: Remove the angle brackets in description, per Sergei
> v2: Add the SHA1 ID in the description, per Sergei
> v1: Initial version
>
> net/ipv4/netfilter/nf_nat_snmp_basic.c | 14 +-------------
> 1 file changed, 1 insertion(+), 13 deletions(-)
>
> diff --git a/net/ipv4/netfilter/nf_nat_snmp_basic.c
> b/net/ipv4/netfilter/nf_nat_snmp_basic.c
> index c9b52c3..5787364 100644
> --- a/net/ipv4/netfilter/nf_nat_snmp_basic.c
> +++ b/net/ipv4/netfilter/nf_nat_snmp_basic.c
> @@ -1260,16 +1260,6 @@ static int help(struct sk_buff *skb, unsigned int
> protoff,
> .timeout = 180,
> };
>
> -static struct nf_conntrack_helper snmp_helper __read_mostly = {
> - .me = THIS_MODULE,
> - .help = help,
> - .expect_policy = &snmp_exp_policy,
> - .name = "snmp",
> - .tuple.src.l3num = AF_INET,
> - .tuple.src.u.udp.port = cpu_to_be16(SNMP_PORT),
> - .tuple.dst.protonum = IPPROTO_UDP,
> -};
> -
> static struct nf_conntrack_helper snmp_trap_helper __read_mostly = {
> .me = THIS_MODULE,
> .help = help,
> @@ -1294,10 +1284,8 @@ static int __init nf_nat_snmp_basic_init(void)
> RCU_INIT_POINTER(nf_nat_snmp_hook, help);
>
> ret = nf_conntrack_helper_register(&snmp_trap_helper);
> - if (ret < 0) {
> - nf_conntrack_helper_unregister(&snmp_helper);
> + if (ret < 0)
> return ret;
> - }
> return ret;
You can provide a more simplified version after this is removed, I
think:
@@ -1283,10 +1283,7 @@ static int __init nf_nat_snmp_basic_init(void)
BUG_ON(nf_nat_snmp_hook != NULL);
RCU_INIT_POINTER(nf_nat_snmp_hook, help);
- ret = nf_conntrack_helper_register(&snmp_trap_helper);
- if (ret < 0)
- return ret;
- return ret;
+ return nf_conntrack_helper_register(&snmp_trap_helper);
}
