cfg80211: scan: fix RCU in cfg80211_add_nontrans_list()

commit a2083eeb119fb9307258baea9b7c243ca9a2e0b6 upstream.

The SSID pointer is pointing to RCU protected data, so we
need to have it under rcu_read_lock() for the entire use.
Fix this.

Cc: stable@vger.kernel.org
Fixes: 0b8fb8235b ("cfg80211: Parsing of Multiple BSSID information in scanning")
Link: https://lore.kernel.org/r/20210930131120.6ddfc603aa1d.I2137344c4e2426525b1a8e4ce5fca82f8ecbfe7e@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johannes Berg 2021-09-30 13:11:21 +02:00 committed by Greg Kroah-Hartman
parent 590abe5bec
commit a37c5e70ac
1 changed files with 5 additions and 2 deletions

View File

@ -379,14 +379,17 @@ cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
}
ssid_len = ssid[1];
ssid = ssid + 2;
rcu_read_unlock();
/* check if nontrans_bss is in the list */
list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len))
if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len)) {
rcu_read_unlock();
return 0;
}
}
rcu_read_unlock();
/* add to the list */
list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
return 0;