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 <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
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;
}