[PATCH] nl80211: Reset split_start when netlink skb is exhausted

[PATCH] nl80211: Reset split_start when netlink skb is exhausted

[Pontus Fuchs]

When the netlink skb is exhausted split_start is left set. In the
subsequent retry, with a larger buffer, the dump is continued from the
failing point instead of from the beginning.

This was causing my rt28xx based USB dongle to now show up when
running "iw list" with an old iw version without split dump support.

Signed-off-by: Pontus Fuchs <pontus.fuchs@gmail.com>
---
 net/wireless/nl80211.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index d0afd82..c7ce4c7 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1725,6 +1725,7 @@ static int nl80211_dump_wiphy(struct sk_buff *skb, struct netlink_callback *cb)
 				    !skb->len &&
 				    cb->min_dump_alloc < 4096) {
 					cb->min_dump_alloc = 4096;
+					state->split_start = 0;
 					rtnl_unlock();
 					return 1;
 				}
-- 
1.8.3.2

Re: [PATCH] nl80211: Reset split_start when netlink skb is exhausted

[Johannes Berg]

On Thu, 2014-01-16 at 15:00 +0100, Pontus Fuchs wrote:
> When the netlink skb is exhausted split_start is left set. In the
> subsequent retry, with a larger buffer, the dump is continued from the
> failing point instead of from the beginning.
> 
> This was causing my rt28xx based USB dongle to now show up when
> running "iw list" with an old iw version without split dump support.

Thanks, applied. I added Cc: stable and Fixes: tags as well as adding "!
state->split" to the conditions.

johannes