From 3e6ccd790ed69bedd3d9626d01dd35cf9821c121 Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Thu, 21 May 2026 10:42:16 +0200 Subject: [PATCH] gpio: cdev: check if uAPI v2 config attributes are correctly zeroed We check the padding of other uAPI v2 structures but not that of line config attributes. For used attributes: check if their padding is zeroed, for unused: check if the entire structure is zeroed. Fixes: 3c0d9c635ae2 ("gpiolib: cdev: support GPIO_V2_GET_LINE_IOCTL and GPIO_V2_LINE_GET_VALUES_IOCTL") Reviewed-by: Kent Gibson Link: https://patch.msgid.link/20260521-gpio-cdev-attr-padding-check-v3-1-ec3bcbe2e358@oss.qualcomm.com Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpiolib-cdev.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index f36b7c06996d..82f27db0b230 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -1184,6 +1184,7 @@ static int gpio_v2_line_flags_validate(u64 flags) static int gpio_v2_line_config_validate(struct gpio_v2_line_config *lc, unsigned int num_lines) { + size_t unused_attrs; unsigned int i; u64 flags; int ret; @@ -1191,9 +1192,21 @@ static int gpio_v2_line_config_validate(struct gpio_v2_line_config *lc, if (lc->num_attrs > GPIO_V2_LINE_NUM_ATTRS_MAX) return -EINVAL; + unused_attrs = GPIO_V2_LINE_NUM_ATTRS_MAX - lc->num_attrs; + if (!mem_is_zero(lc->padding, sizeof(lc->padding))) return -EINVAL; + for (i = 0; i < lc->num_attrs; i++) { + if (lc->attrs[i].attr.padding != 0) + return -EINVAL; + } + + if (unused_attrs) { + if (!mem_is_zero(&lc->attrs[lc->num_attrs], unused_attrs * sizeof(*lc->attrs))) + return -EINVAL; + } + for (i = 0; i < num_lines; i++) { flags = gpio_v2_line_config_flags(lc, i); ret = gpio_v2_line_flags_validate(flags);