On Thu, Oct 20, 2016 at 12:40 PM, Cong Wang <[email protected]> wrote:
> On Thu, Oct 20, 2016 at 12:32 PM, Cong Wang <[email protected]> wrote:
>> On Thu, Oct 20, 2016 at 10:26 AM, Eric Dumazet <[email protected]>
>> wrote:
>>> From: Eric Dumazet <[email protected]>
>>>
>>> In commit 4ee3bd4a8c746 ("ipv4: disable BH when changing ip local port
>>> range") Cong added BH protection in set_local_port_range() but missed
>>> that same fix was needed in set_ping_group_range()
>>
>> Don't know why ping_group_range shares the same lock with local_port_range...
>> Perhaps just for saving a few bytes, but that is why I missed this place.
>
> Hold on... We clearly have typos there... Your fix is not correct.
We need the attached patch, your patch should be reverted, because
unlike local_port_range we never read it in BH context, no need to bother _bh.
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 1cb67de..80bc36b 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -96,11 +96,11 @@ static void inet_get_ping_group_range_table(struct
ctl_table *table, kgid_t *low
container_of(table->data, struct net,
ipv4.ping_group_range.range);
unsigned int seq;
do {
- seq = read_seqbegin(&net->ipv4.ip_local_ports.lock);
+ seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
*low = data[0];
*high = data[1];
- } while (read_seqretry(&net->ipv4.ip_local_ports.lock, seq));
+ } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
}
/* Update system visible IP port range */
@@ -109,10 +109,10 @@ static void set_ping_group_range(struct ctl_table *table,
kgid_t low, kgid_t hig
kgid_t *data = table->data;
struct net *net =
container_of(table->data, struct net,
ipv4.ping_group_range.range);
- write_seqlock(&net->ipv4.ip_local_ports.lock);
+ write_seqlock(&net->ipv4.ping_group_range.lock);
data[0] = low;
data[1] = high;
- write_sequnlock(&net->ipv4.ip_local_ports.lock);
+ write_sequnlock(&net->ipv4.ping_group_range.lock);
}
/* Validate changes from /proc interface. */
