2013-06-11 14:53:14

by Johannes Berg

[permalink] [raw]
Subject: [PATCH] cfg80211: fix rtnl leak in wiphy dump error cases

From: Johannes Berg <[email protected]>

In two wiphy dump error cases, most often when the dump allocation
must be increased, the RTNL is leaked. This quickly results in a
complete system lockup. Release the RTNL correctly.

Reported-by: Emmanuel Grumbach <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
---
net/wireless/nl80211.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 398ce2c..e402819 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1541,8 +1541,10 @@ static int nl80211_dump_wiphy(struct sk_buff *skb, struct netlink_callback *cb)
int ifidx = nla_get_u32(tb[NL80211_ATTR_IFINDEX]);

netdev = dev_get_by_index(sock_net(skb->sk), ifidx);
- if (!netdev)
+ if (!netdev) {
+ rtnl_unlock();
return -ENODEV;
+ }
if (netdev->ieee80211_ptr) {
dev = wiphy_to_dev(
netdev->ieee80211_ptr->wiphy);
@@ -1586,6 +1588,7 @@ 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;
+ rtnl_unlock();
return 1;
}
idx--;
--
1.8.0