Subject: [PATCH AUTOSEL 4.9 028/141] libertas: don't exit from lbs_ibss_join_existing() with RCU read lock held

From: Sasha Levin <[email-masked]>
Date: Fri, 14 Feb 2020 11:19:28 -0500

From: Nicolai Stange <[email-masked]>

[ Upstream commit c7bf1fb7ddca331780b9a733ae308737b39f1ad4 ]

Commit e5e884b42639 ("libertas: Fix two buffer overflows at parsing bss
descriptor") introduced a bounds check on the number of supplied rates to
lbs_ibss_join_existing().

Unfortunately, it introduced a return path from within a RCU read side
critical section without a corresponding rcu_read_unlock(). Fix this.

Fixes: e5e884b42639 ("libertas: Fix two buffer overflows at parsing bss descriptor")
Signed-off-by: Nicolai Stange <[email-masked]>
Signed-off-by: Kalle Valo <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/wireless/marvell/libertas/cfg.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/marvell/libertas/cfg.c b/drivers/net/wireless/marvell/libertas/cfg.c
index 3eab802c7d3f3..0b61942fedd90 100644
--- a/drivers/net/wireless/marvell/libertas/cfg.c
+++ b/drivers/net/wireless/marvell/libertas/cfg.c
@@ -1859,6 +1859,7 @@ static int lbs_ibss_join_existing(struct lbs_private *priv,
 		rates_max = rates_eid[1];
 		if (rates_max > MAX_RATES) {
 			lbs_deb_join("invalid rates");
+			rcu_read_unlock();
 			goto out;
 		}
 		rates = cmd.bss.rates;
-- 
2.20.1