nl80211: Allow GET_INTERFACE dumps to be filtered
This patch allows GET_INTERFACE dumps to be filtered based on
NL80211_ATTR_WIPHY or NL80211_ATTR_WDEV. The documentation for
GET_INTERFACE mentions that this is possible:
"Request an interface's configuration; either a dump request on
a %NL80211_ATTR_WIPHY or ..."
However, this behavior has not been implemented until now.
Johannes: rewrite most of the patch:
* use nl80211_dump_wiphy_parse() to also allow passing an interface
to be able to dump its siblings
* fix locking (must hold rtnl around using nl80211_fam.attrbuf)
* make init self-contained instead of relying on other cb->args
Signed-off-by: Denis Kenzior <denkenz@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 4997857..7ebad35 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2525,10 +2525,35 @@
int if_idx = 0;
int wp_start = cb->args[0];
int if_start = cb->args[1];
+ int filter_wiphy = -1;
struct cfg80211_registered_device *rdev;
struct wireless_dev *wdev;
rtnl_lock();
+ if (!cb->args[2]) {
+ struct nl80211_dump_wiphy_state state = {
+ .filter_wiphy = -1,
+ };
+ int ret;
+
+ ret = nl80211_dump_wiphy_parse(skb, cb, &state);
+ if (ret)
+ return ret;
+
+ filter_wiphy = state.filter_wiphy;
+
+ /*
+ * if filtering, set cb->args[2] to +1 since 0 is the default
+ * value needed to determine that parsing is necessary.
+ */
+ if (filter_wiphy >= 0)
+ cb->args[2] = filter_wiphy + 1;
+ else
+ cb->args[2] = -1;
+ } else if (cb->args[2] > 0) {
+ filter_wiphy = cb->args[2] - 1;
+ }
+
list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
if (!net_eq(wiphy_net(&rdev->wiphy), sock_net(skb->sk)))
continue;
@@ -2536,6 +2561,10 @@
wp_idx++;
continue;
}
+
+ if (filter_wiphy >= 0 && filter_wiphy != rdev->wiphy_idx)
+ continue;
+
if_idx = 0;
list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {