From 48619ac82b58833de45bbe2d50da2419ade04df0 Mon Sep 17 00:00:00 2001
From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Sat, 5 Feb 2022 08:40:48 +0100
Subject: backlight: pwm_bl: Avoid open coded arithmetic in memory allocation
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Git-commit: ba9897a0e0cefcff0108d856aa754b953997d920
Patch-mainline: v5.18-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
kmalloc_array()/kcalloc() should be used to avoid potential overflow when
a multiplication is needed to compute the size of the requested memory.
So turn a kzalloc()+explicit size computation into an equivalent kcalloc().
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/bd3d74acfa58d59f6f5f81fc5a9fb409edb8d747.1644046817.git.christophe.jaillet@wanadoo.fr
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/video/backlight/pwm_bl.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
index 8d8959a70e44..c0523a0269ee 100644
--- a/drivers/video/backlight/pwm_bl.c
+++ b/drivers/video/backlight/pwm_bl.c
@@ -263,9 +263,8 @@ static int pwm_backlight_parse_dt(struct device *dev,
/* read brightness levels from DT property */
if (num_levels > 0) {
- size_t size = sizeof(*data->levels) * num_levels;
-
- data->levels = devm_kzalloc(dev, size, GFP_KERNEL);
+ data->levels = devm_kcalloc(dev, num_levels,
+ sizeof(*data->levels), GFP_KERNEL);
if (!data->levels)
return -ENOMEM;
@@ -320,8 +319,8 @@ static int pwm_backlight_parse_dt(struct device *dev,
* Create a new table of brightness levels with all the
* interpolated steps.
*/
- size = sizeof(*table) * num_levels;
- table = devm_kzalloc(dev, size, GFP_KERNEL);
+ table = devm_kcalloc(dev, num_levels, sizeof(*table),
+ GFP_KERNEL);
if (!table)
return -ENOMEM;
/*
--
2.38.1