[PATCH v2] ARM/dma-mapping: use kvzalloc() in __iommu_alloc_buffer()

From: Denis Efremov <efremov@linux.com>
To: linux-arm-kernel@lists.infradead.org
Cc: Denis Efremov <efremov@linux.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org,
	Russell King <linux@armlinux.org.uk>
Subject: [PATCH v2] ARM/dma-mapping: use kvzalloc() in __iommu_alloc_buffer()
Date: Thu, 27 Aug 2020 18:43:32 +0300	[thread overview]
Message-ID: <20200827154332.41571-1-efremov@linux.com> (raw)
In-Reply-To: <20200827151541.39662-1-efremov@linux.com>

Use kvzalloc() in __iommu_alloc_buffer() instead of open-coding it.
Size computation wrapped in array_size() macro to prevent potential
integer overflows.

Signed-off-by: Denis Efremov <efremov@linux.com>
---
Changes in v2:
 - array_size() added

 arch/arm/mm/dma-mapping.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 8a8949174b1c..c1f864ff7b84 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1199,14 +1199,10 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t size,
 {
 	struct page **pages;
 	int count = size >> PAGE_SHIFT;
-	int array_size = count * sizeof(struct page *);
 	int i = 0;
 	int order_idx = 0;
 
-	if (array_size <= PAGE_SIZE)
-		pages = kzalloc(array_size, GFP_KERNEL);
-	else
-		pages = vzalloc(array_size);
+	pages = kvzalloc(array_size(sizeof(*pages), count), GFP_KERNEL);
 	if (!pages)
 		return NULL;
 
-- 
2.26.2

