[PATCH 01/10] iommu/amd: take into account that alloc_dev_data() may return NULL

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
	tglx@linutronix.de, Scott Wood <swood@redhat.com>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	Baoquan He <bhe@redhat.com>
Subject: [PATCH 01/10] iommu/amd: take into account that alloc_dev_data() may return NULL
Date: Thu, 22 Mar 2018 16:22:33 +0100	[thread overview]
Message-ID: <20180322152242.12705-2-bigeasy@linutronix.de> (raw)
In-Reply-To: <20180322152242.12705-1-bigeasy@linutronix.de>

find_dev_data() does not check whether the return value alloc_dev_data()
is NULL. This was okay once because the pointer was returned once as-is.
Since commit df3f7a6e8e85 ("iommu/amd: Use is_attach_deferred
call-back") the pointer may be used within find_dev_data() so a NULL
check is required.

Cc: Baoquan He <bhe@redhat.com>
Fixes: df3f7a6e8e85 ("iommu/amd: Use is_attach_deferred call-back")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 drivers/iommu/amd_iommu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 4cd19f93ca15..121c54f1c768 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -310,6 +310,8 @@ static struct iommu_dev_data *find_dev_data(u16 devid)
 
 	if (dev_data == NULL) {
 		dev_data = alloc_dev_data(devid);
+		if (!dev_data)
+			return NULL;
 
 		if (translation_pre_enabled(iommu))
 			dev_data->defer_attach = true;
-- 
2.16.2
