[PATCH 5.1 119/121] nl80211: fix station_info pertid memory leak

From: Greg Kroah-Hartman
Date: Mon Jun 24 2019 - 06:21:58 EST


From: Andy Strohman <andrew@xxxxxxxxxxxxxxxxxx>

commit f77bf4863dc2218362f4227d56af4a5f3f08830c upstream.

When dumping stations, memory allocated for station_info's
pertid member will leak if the nl80211 header cannot be added to
the sk_buff due to insufficient tail room.

I noticed this leak in the kmalloc-2048 cache.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 8689c051a201 ("cfg80211: dynamically allocate per-tid stats for station info")
Signed-off-by: Andy Strohman <andy@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/wireless/nl80211.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -4804,8 +4804,10 @@ static int nl80211_send_station(struct s
struct nlattr *sinfoattr, *bss_param;

hdr = nl80211hdr_put(msg, portid, seq, flags, cmd);
- if (!hdr)
+ if (!hdr) {
+ cfg80211_sinfo_release_content(sinfo);
return -1;
+ }

if (nla_put_u32(msg, NL80211_ATTR_IFINDEX, dev->ifindex) ||
nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr) ||