diff options
| author | Dominik Brodowski <linux@dominikbrodowski.net> | 2018-01-15 08:12:15 +0100 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2018-01-15 09:15:04 +0100 |
| commit | 7a94b8c2eee7083ddccd0515830f8c81a8e44b1a (patch) | |
| tree | 97ecb540ce522008ac03bc7840ee2da0b9c0a5a3 | |
| parent | a48a52b7bea81c046fe1c1288f84d0eba214cba0 (diff) | |
| download | linux-4.1-7a94b8c2eee7083ddccd0515830f8c81a8e44b1a.tar.gz | |
nl80211: take RCU read lock when calling ieee80211_bss_get_ie()
As ieee80211_bss_get_ie() derefences an RCU to return ssid_ie, both
the call to this function and any operation on this variable need
protection by the RCU read lock.
Fixes: 44905265bc15 ("nl80211: don't expose wdev->ssid for most interfaces")
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
| -rw-r--r-- | net/wireless/nl80211.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 2b3dbcd40e4639..ed87a97fcb0b04 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -2618,12 +2618,13 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 portid, u32 seq, int flag const u8 *ssid_ie; if (!wdev->current_bss) break; + rcu_read_lock(); ssid_ie = ieee80211_bss_get_ie(&wdev->current_bss->pub, WLAN_EID_SSID); - if (!ssid_ie) - break; - if (nla_put(msg, NL80211_ATTR_SSID, ssid_ie[1], ssid_ie + 2)) - goto nla_put_failure_locked; + if (ssid_ie && + nla_put(msg, NL80211_ATTR_SSID, ssid_ie[1], ssid_ie + 2)) + goto nla_put_failure_rcu_locked; + rcu_read_unlock(); break; } default: @@ -2635,6 +2636,8 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 portid, u32 seq, int flag genlmsg_end(msg, hdr); return 0; + nla_put_failure_rcu_locked: + rcu_read_unlock(); nla_put_failure_locked: wdev_unlock(wdev); nla_put_failure: |