diff mbox

[v3,3/3] net: Dynamically allocate struct station_info

Message ID 152593681727.16852.3053716209715237526.stgit@alrua-kau (mailing list archive)
State Rejected
Delegated to: Johannes Berg
Headers show

Commit Message

Toke Høiland-Jørgensen May 10, 2018, 7:20 a.m. UTC
Since the addition of the TXQ stats to cfg80211, the station_info struct
has grown to be quite large, which results in warnings when allocated on
the stack. Fix the affected places to do dynamic allocations instead.

This patch applies the fix to batman-adv and wext-compat, while a
separate patch fixes up the drivers.

Fixes: 52539ca89f36 ("cfg80211: Expose TXQ stats and parameters to userspace")
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
---
 net/batman-adv/bat_v_elp.c |   22 ++++++++++++++++------
 net/wireless/wext-compat.c |   29 +++++++++++++++++------------
 2 files changed, 33 insertions(+), 18 deletions(-)
diff mbox

Patch

diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
index 28687493599f..42dd700b8d8d 100644
--- a/net/batman-adv/bat_v_elp.c
+++ b/net/batman-adv/bat_v_elp.c
@@ -79,8 +79,9 @@  static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
 	struct batadv_hard_iface *hard_iface = neigh->if_incoming;
 	struct ethtool_link_ksettings link_settings;
 	struct net_device *real_netdev;
-	struct station_info sinfo;
+	struct station_info *sinfo;
 	u32 throughput;
+	bool filled;
 	int ret;
 
 	/* if the user specified a customised value for this interface, then
@@ -102,7 +103,18 @@  static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
 		if (!real_netdev)
 			goto default_throughput;
 
-		ret = cfg80211_get_station(real_netdev, neigh->addr, &sinfo);
+		sinfo = kzalloc(sizeof(*sinfo), GFP_KERNEL);
+		if (!sinfo)
+			goto default_throughput;
+
+		ret = cfg80211_get_station(real_netdev, neigh->addr, sinfo);
+
+		/* save these here to avoid complex free logic below */
+		throughput = sinfo->expected_throughput / 100;
+		filled = (sinfo->filled &
+			  BIT(NL80211_STA_INFO_EXPECTED_THROUGHPUT));
+
+		kfree(sinfo);
 
 		dev_put(real_netdev);
 		if (ret == -ENOENT) {
@@ -112,12 +124,10 @@  static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
 			 */
 			return 0;
 		}
-		if (ret)
-			goto default_throughput;
-		if (!(sinfo.filled & BIT(NL80211_STA_INFO_EXPECTED_THROUGHPUT)))
+		if (ret || !filled)
 			goto default_throughput;
 
-		return sinfo.expected_throughput / 100;
+		return throughput;
 	}
 
 	/* if not a wifi interface, check if this device provides data via
diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
index 9e002df0f8d8..2038e3fb25fa 100644
--- a/net/wireless/wext-compat.c
+++ b/net/wireless/wext-compat.c
@@ -1300,7 +1300,7 @@  static struct iw_statistics *cfg80211_wireless_stats(struct net_device *dev)
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
 	/* we are under RTNL - globally locked - so can use static structs */
 	static struct iw_statistics wstats;
-	static struct station_info sinfo;
+	static struct station_info *sinfo;
 	u8 bssid[ETH_ALEN];
 
 	if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_STATION)
@@ -1318,17 +1318,21 @@  static struct iw_statistics *cfg80211_wireless_stats(struct net_device *dev)
 	memcpy(bssid, wdev->current_bss->pub.bssid, ETH_ALEN);
 	wdev_unlock(wdev);
 
-	memset(&sinfo, 0, sizeof(sinfo));
+	sinfo = kzalloc(sizeof(*sinfo), GFP_KERNEL);
+	if (!sinfo)
+		return NULL;
 
-	if (rdev_get_station(rdev, dev, bssid, &sinfo))
+	if (rdev_get_station(rdev, dev, bssid, sinfo)) {
+		kfree(sinfo);
 		return NULL;
+	}
 
 	memset(&wstats, 0, sizeof(wstats));
 
 	switch (rdev->wiphy.signal_type) {
 	case CFG80211_SIGNAL_TYPE_MBM:
-		if (sinfo.filled & BIT(NL80211_STA_INFO_SIGNAL)) {
-			int sig = sinfo.signal;
+		if (sinfo->filled & BIT(NL80211_STA_INFO_SIGNAL)) {
+			int sig = sinfo->signal;
 			wstats.qual.updated |= IW_QUAL_LEVEL_UPDATED;
 			wstats.qual.updated |= IW_QUAL_QUAL_UPDATED;
 			wstats.qual.updated |= IW_QUAL_DBM;
@@ -1341,11 +1345,11 @@  static struct iw_statistics *cfg80211_wireless_stats(struct net_device *dev)
 			break;
 		}
 	case CFG80211_SIGNAL_TYPE_UNSPEC:
-		if (sinfo.filled & BIT(NL80211_STA_INFO_SIGNAL)) {
+		if (sinfo->filled & BIT(NL80211_STA_INFO_SIGNAL)) {
 			wstats.qual.updated |= IW_QUAL_LEVEL_UPDATED;
 			wstats.qual.updated |= IW_QUAL_QUAL_UPDATED;
-			wstats.qual.level = sinfo.signal;
-			wstats.qual.qual = sinfo.signal;
+			wstats.qual.level = sinfo->signal;
+			wstats.qual.qual = sinfo->signal;
 			break;
 		}
 	default:
@@ -1354,11 +1358,12 @@  static struct iw_statistics *cfg80211_wireless_stats(struct net_device *dev)
 	}
 
 	wstats.qual.updated |= IW_QUAL_NOISE_INVALID;
-	if (sinfo.filled & BIT(NL80211_STA_INFO_RX_DROP_MISC))
-		wstats.discard.misc = sinfo.rx_dropped_misc;
-	if (sinfo.filled & BIT(NL80211_STA_INFO_TX_FAILED))
-		wstats.discard.retries = sinfo.tx_failed;
+	if (sinfo->filled & BIT(NL80211_STA_INFO_RX_DROP_MISC))
+		wstats.discard.misc = sinfo->rx_dropped_misc;
+	if (sinfo->filled & BIT(NL80211_STA_INFO_TX_FAILED))
+		wstats.discard.retries = sinfo->tx_failed;
 
+	kfree(sinfo);
 	return &wstats;
 }