This is a note to let you know that I've just added the patch titled
cfg80211: scan: fix RCU in cfg80211_add_nontrans_list()
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cfg80211-scan-fix-rcu-in-cfg80211_add_nontrans_list.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a2083eeb119fb9307258baea9b7c243ca9a2e0b6 Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@xxxxxxxxx>
Date: Thu, 30 Sep 2021 13:11:21 +0200
Subject: cfg80211: scan: fix RCU in cfg80211_add_nontrans_list()
From: Johannes Berg <johannes.berg@xxxxxxxxx>
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@xxxxxxxxxxxxxxx
Fixes: 0b8fb8235be8 ("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@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/wireless/scan.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -418,14 +418,17 @@ cfg80211_add_nontrans_list(struct cfg802
}
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;
Patches currently in stable-queue which might be from johannes.berg@xxxxxxxxx are
queue-5.10/cfg80211-fix-management-registrations-locking.patch
queue-5.10/cfg80211-scan-fix-rcu-in-cfg80211_add_nontrans_list.patch
