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Date: Sun, 21 Feb 2016 17:08:32 +0530
From: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
To: outreachy-kernel@googlegroups.com
Subject: [PATCH] staging: fbtft:  Prefer using kmalloc_array
Message-ID: <20160221113832.GA28242@Karyakshetra>
MIME-Version: 1.0
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Content-Disposition: inline
User-Agent: Mutt/1.5.23 (2014-03-12)

Use kmalloc_array instead of kmalloc for arrays to prevent integer
overflows.
This was done using Coccinelle:
@@
expression e1, e2;
constant C;
type t;
@@
(
- kmalloc(sizeof(e1)*e2, C)
+ kmalloc_array(e2, sizeof(e1), C)
|
- kmalloc(e2*sizeof(e1), C)
+ kmalloc_array(e2, sizeof(e1), C)
|
- kmalloc(e2*sizeof(t), C)
+ kmalloc_array(e2, sizeof(t), C)
|
- kmalloc(sizeof(t)*e2, C)
+ kmalloc_array(e2, sizeof(t), C)
)

Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
---
 drivers/staging/fbtft/fb_agm1264k-fl.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/fbtft/fb_agm1264k-fl.c b/drivers/staging/fbtft/fb_agm1264k-fl.c
index 2a50cf9..5fbfd50 100644
--- a/drivers/staging/fbtft/fb_agm1264k-fl.c
+++ b/drivers/staging/fbtft/fb_agm1264k-fl.c
@@ -272,8 +272,9 @@ static int write_vmem(struct fbtft_par *par, size_t offset, size_t len)
 	int ret = 0;

 	/* buffer to convert RGB565 -> grayscale16 -> Dithered image 1bpp */
-	signed short *convert_buf = kmalloc(par->info->var.xres *
-		par->info->var.yres * sizeof(signed short), GFP_NOIO);
+	signed short *convert_buf = kmalloc_array(par->info->var.xres * par->info->var.yres,
+						  sizeof(signed short),
+						  GFP_NOIO);

 	if (!convert_buf)
 		return -ENOMEM;
--
2.1.4