In the quest to remove all stack VLA usage from the kernel[1], this
allocates the values buffer during the callback instead of putting it
on the stack.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
struct mdio_mux_gpio_state {
struct gpio_descs *gpios;
void *mux_handle;
struct mdio_mux_gpio_state {
struct gpio_descs *gpios;
void *mux_handle;
};
static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
void *data)
{
struct mdio_mux_gpio_state *s = data;
};
static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
void *data)
{
struct mdio_mux_gpio_state *s = data;
- int values[s->gpios->ndescs];
unsigned int n;
if (current_child == desired_child)
return 0;
for (n = 0; n < s->gpios->ndescs; n++)
unsigned int n;
if (current_child == desired_child)
return 0;
for (n = 0; n < s->gpios->ndescs; n++)
- values[n] = (desired_child >> n) & 1;
+ s->values[n] = (desired_child >> n) & 1;
gpiod_set_array_value_cansleep(s->gpios->ndescs, s->gpios->desc,
gpiod_set_array_value_cansleep(s->gpios->ndescs, s->gpios->desc,
static int mdio_mux_gpio_probe(struct platform_device *pdev)
{
struct mdio_mux_gpio_state *s;
static int mdio_mux_gpio_probe(struct platform_device *pdev)
{
struct mdio_mux_gpio_state *s;
+ struct gpio_descs *gpios;
- s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
- if (!s)
+ gpios = gpiod_get_array(&pdev->dev, NULL, GPIOD_OUT_LOW);
+ if (IS_ERR(gpios))
+ return PTR_ERR(gpios);
+
+ s = devm_kzalloc(&pdev->dev, struct_size(s, values, gpios->ndescs),
+ GFP_KERNEL);
+ if (!s) {
+ gpiod_put_array(gpios);
- s->gpios = gpiod_get_array(&pdev->dev, NULL, GPIOD_OUT_LOW);
- if (IS_ERR(s->gpios))
- return PTR_ERR(s->gpios);
r = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
mdio_mux_gpio_switch_fn, &s->mux_handle, s, NULL);
r = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
mdio_mux_gpio_switch_fn, &s->mux_handle, s, NULL);