From b7fb44dacae04219c82f20897382ba34860d1a16 Mon Sep 17 00:00:00 2001 From: Denis Kenzior Date: Wed, 3 Aug 2016 17:02:15 -0500 Subject: [PATCH] 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 Signed-off-by: Johannes Berg --- net/wireless/nl80211.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 499785778983..7ebad350abc1 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -2525,10 +2525,35 @@ static int nl80211_dump_interface(struct sk_buff *skb, struct netlink_callback * 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 @@ static int nl80211_dump_interface(struct sk_buff *skb, struct netlink_callback * 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) { -- 2.30.2