From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Date: Mon, 10 Feb 2025 10:51:59 +0000 (+0100)
Subject: gpiolib: sanitize the return value of gpio_chip::get_multiple()
X-Git-Tag: v6.15-rc1~179^2~84
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=74abd086d2ee5ef10f68848cfe39e271ac798685;p=thirdparty%2Flinux.git

gpiolib: sanitize the return value of gpio_chip::get_multiple()

As per the API contract, the get_multiple() callback is only allowed to
return 0 or a negative error number. Filter out anything else.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-5-12ea88506cb2@linaro.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 1a3f527aba0ea..9ac2dad0ad342 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -3182,10 +3182,16 @@ static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
 static int gpio_chip_get_multiple(struct gpio_chip *gc,
 				  unsigned long *mask, unsigned long *bits)
 {
+	int ret;
+	
 	lockdep_assert_held(&gc->gpiodev->srcu);
 
-	if (gc->get_multiple)
-		return gc->get_multiple(gc, mask, bits);
+	if (gc->get_multiple) {
+		ret = gc->get_multiple(gc, mask, bits);
+		if (ret > 0)
+			return -EBADE;
+	}
+
 	if (gc->get) {
 		int i, value;