From 8c7c1a207d25cd880c7f54d3fe86e82f14d6ecda Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Fri, 21 Aug 2020 12:52:15 +0200 Subject: [PATCH] mt76: fix a possible NULL pointer dereference in mt76_testmode_dump Fix a possible NULL pointer dereference in mt76_testmode_dump() since nla_nest_start returns NULL in case of error Fixes: f0efa8621550e ("mt76: add API for testmode support") Signed-off-by: Lorenzo Bianconi Signed-off-by: Felix Fietkau --- testmode.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/testmode.c b/testmode.c index 3be4e2ff..1653f0b1 100644 --- a/testmode.c +++ b/testmode.c @@ -442,9 +442,13 @@ int mt76_testmode_dump(struct ieee80211_hw *hw, struct sk_buff *msg, mutex_lock(&dev->mutex); if (tb[MT76_TM_ATTR_STATS]) { + err = -EINVAL; + a = nla_nest_start(msg, MT76_TM_ATTR_STATS); - err = mt76_testmode_dump_stats(dev, msg); - nla_nest_end(msg, a); + if (a) { + err = mt76_testmode_dump_stats(dev, msg); + nla_nest_end(msg, a); + } goto out; }