[PATCH] leds: aat1290: Allocate mm_current_scale with ARRAY_SIZE()

[PATCH] leds: aat1290: Allocate mm_current_scale with ARRAY_SIZE()

[Kees Cook]

From: Kees Cook <kees+treewide@kernel.org>

In preparation for making the devm_kmalloc family of allocators type
aware, we need to make sure that the returned type from the allocation
matches the type of the variable being assigned. (Before, the allocator
would always return "void *", which can be implicitly cast to any
pointer type.)

This allocates one int per entry of max_mm_current_percent, but the size
was taken from the whole array, which would make the allocation type a
pointer to the array rather than the "int *" being assigned. Allocate
ARRAY_SIZE-many entries instead. The resulting allocation size is the
same: AAT1290_MM_CURRENT_SCALE_SIZE and
ARRAY_SIZE(max_mm_current_percent) are both 15.

Build tested ARCH=x86_64 allmodconfig with GCC 16.2.0:
drivers/leds/flash/leds-aat1290.o

Assisted-by: LLM coccinelle
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
---
Cc: Lee Jones <lee@kernel.org>
Cc: Pavel Machek <pavel@kernel.org>
Cc: "Uwe Kleine-König" <u.kleine-koenig@baylibre.com>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: <linux-leds@vger.kernel.org>
---
 drivers/leds/flash/leds-aat1290.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/leds/flash/leds-aat1290.c b/drivers/leds/flash/leds-aat1290.c
index 49251cfd3350..4bde0b07fe78 100644
--- a/drivers/leds/flash/leds-aat1290.c
+++ b/drivers/leds/flash/leds-aat1290.c
@@ -311,8 +311,9 @@ static int init_mm_current_scale(struct aat1290_led *led,
 	int i, max_mm_current =
 			AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
 
-	led->mm_current_scale = devm_kzalloc(&led->pdev->dev,
-					sizeof(max_mm_current_percent),
+	led->mm_current_scale = devm_kcalloc(&led->pdev->dev,
+					ARRAY_SIZE(max_mm_current_percent),
+					sizeof(*led->mm_current_scale),
 					GFP_KERNEL);
 	if (!led->mm_current_scale)
 		return -ENOMEM;
-- 
2.34.1

Re: (subset) [PATCH] leds: aat1290: Allocate mm_current_scale with ARRAY_SIZE()

[Lee Jones]

On Thu, 17 Sep 2026 14:13:58 -0700, Kees Cook wrote:
> In preparation for making the devm_kmalloc family of allocators type
> aware, we need to make sure that the returned type from the allocation
> matches the type of the variable being assigned. (Before, the allocator
> would always return "void *", which can be implicitly cast to any
> pointer type.)
> 
> This allocates one int per entry of max_mm_current_percent, but the size
> was taken from the whole array, which would make the allocation type a
> pointer to the array rather than the "int *" being assigned. Allocate
> ARRAY_SIZE-many entries instead. The resulting allocation size is the
> same: AAT1290_MM_CURRENT_SCALE_SIZE and
> ARRAY_SIZE(max_mm_current_percent) are both 15.
> 
> [...]

Applied, thanks!

[1/1] leds: aat1290: Allocate mm_current_scale with ARRAY_SIZE()
      commit: 4893d51ed4d7f3c0254543c0b5f2b307c8728eff

--
Lee Jones [李琼斯]