From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 20 May 2020 12:03:06 +0000 (+0300)
Subject: iio: dummy_evgen: Fix use after free on error in iio_dummy_evgen_create()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=128516e49de67d10d52fba62ef8d482b220ac4b0;p=linux.git

iio: dummy_evgen: Fix use after free on error in iio_dummy_evgen_create()

We need to preserve the "iio_evgen->irq_sim_domain" error code before
we free "iio_evgen" otherwise it leads to a use after free.

Fixes: 337cbeb2c13e ("genirq/irq_sim: Simplify the API")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---

diff --git a/drivers/iio/dummy/iio_dummy_evgen.c b/drivers/iio/dummy/iio_dummy_evgen.c
index 409fe0f7df1cd..ee85d596e5284 100644
--- a/drivers/iio/dummy/iio_dummy_evgen.c
+++ b/drivers/iio/dummy/iio_dummy_evgen.c
@@ -45,6 +45,8 @@ static struct iio_dummy_eventgen *iio_evgen;
 
 static int iio_dummy_evgen_create(void)
 {
+	int ret;
+
 	iio_evgen = kzalloc(sizeof(*iio_evgen), GFP_KERNEL);
 	if (!iio_evgen)
 		return -ENOMEM;
@@ -52,8 +54,9 @@ static int iio_dummy_evgen_create(void)
 	iio_evgen->irq_sim_domain = irq_domain_create_sim(NULL,
 							  IIO_EVENTGEN_NO);
 	if (IS_ERR(iio_evgen->irq_sim_domain)) {
+		ret = PTR_ERR(iio_evgen->irq_sim_domain);
 		kfree(iio_evgen);
-		return PTR_ERR(iio_evgen->irq_sim_domain);
+		return ret;
 	}
 
 	mutex_init(&iio_evgen->lock);