5.4-stable review patch. If anyone has any objections, please let me know.
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From: Dmitry Antipov dmantipov@yandex.ru
[ Upstream commit 26e84445f02ce6b2fe5f3e0e28ff7add77f35e08 ]
Following bss_free() quirk introduced in commit 776b3580178f ("cfg80211: track hidden SSID networks properly"), adjust cfg80211_update_known_bss() to free the last beacon frame elements only if they're not shared via the corresponding 'hidden_beacon_bss' pointer.
Reported-by: syzbot+30754ca335e6fb7e3092@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=30754ca335e6fb7e3092 Fixes: 3ab8227d3e7d ("cfg80211: refactor cfg80211_bss_update") Signed-off-by: Dmitry Antipov dmantipov@yandex.ru Link: https://patch.msgid.link/20250813135236.799384-1-dmantipov@yandex.ru Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/wireless/scan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 18398968b3ed7..33e6f41035506 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -1219,7 +1219,8 @@ cfg80211_update_known_bss(struct cfg80211_registered_device *rdev, */
f = rcu_access_pointer(new->pub.beacon_ies); - kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head); + if (!new->pub.hidden_beacon_bss) + kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head); return false; }