diff options
| author | Dominik Brodowski <linux@dominikbrodowski.net> | 2018-01-15 08:12:15 +0100 |
|---|---|---|
| committer | Moyster <oysterized@gmail.com> | 2019-05-03 19:27:38 +0200 |
| commit | ec4eaf79b19452599b0c1b3bbcf8fff81afaa9b7 (patch) | |
| tree | 8ba11b72e02022c5b65271b1bbfc84bc90c70f9d /net | |
| parent | 7a17b3012a24fb479fa911cec84babf74c646e60 (diff) | |
nl80211: take RCU read lock when calling ieee80211_bss_get_ie()
commit 7a94b8c2eee7083ddccd0515830f8c81a8e44b1a upstream.
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")
Change-Id: I7d9c6c32135f4be34678537653787654d435116e
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net')
| -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 3431c2329..261efbbb1 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -2266,12 +2266,13 @@ 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: @@ -2282,6 +2283,8 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 portid, u32 seq, int flag return genlmsg_end(msg, hdr); + nla_put_failure_rcu_locked: + rcu_read_unlock(); nla_put_failure_locked: wdev_unlock(wdev); nla_put_failure: |