diff options
| author | Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com> | 2025-12-22 13:01:27 +0300 |
|---|---|---|
| committer | Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com> | 2026-01-02 12:34:31 +0300 |
| commit | cb0451e33be047fff7137f58d9996370e11fb344 (patch) | |
| tree | 82001c14df236e540fcb8aa736ef4c1dbb230886 | |
| parent | 9700b0fccf386b671e6f8401ddea6c5669cd0914 (diff) | |
| download | linux-cb0451e33be047fff7137f58d9996370e11fb344.tar.xz | |
gpio: shared: verify con_id when adding proxy lookup
When matching the firmware node with the potential consumer, we
currently omit the con_id string. This can lead to false positives in
the unlikely case of the consumer having been assigned more than one
shared GPIO. Check the connector ID before proceeding.
Fixes: a060b8c511ab ("gpiolib: implement low-level, shared GPIO support")
Link: https://lore.kernel.org/r/20251222-gpio-shared-reset-gpio-proxy-v1-2-8d4bba7d8c14@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
| -rw-r--r-- | drivers/gpio/gpiolib-shared.c | 7 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib-shared.h | 4 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib.c | 3 |
3 files changed, 11 insertions, 3 deletions
diff --git a/drivers/gpio/gpiolib-shared.c b/drivers/gpio/gpiolib-shared.c index ba4b718d40a0..f589109590c7 100644 --- a/drivers/gpio/gpiolib-shared.c +++ b/drivers/gpio/gpiolib-shared.c @@ -365,7 +365,8 @@ static bool gpio_shared_dev_is_reset_gpio(struct device *consumer, } #endif /* CONFIG_RESET_GPIO */ -int gpio_shared_add_proxy_lookup(struct device *consumer, unsigned long lflags) +int gpio_shared_add_proxy_lookup(struct device *consumer, const char *con_id, + unsigned long lflags) { const char *dev_id = dev_name(consumer); struct gpio_shared_entry *entry; @@ -384,6 +385,10 @@ int gpio_shared_add_proxy_lookup(struct device *consumer, unsigned long lflags) guard(mutex)(&ref->lock); + if ((!con_id && ref->con_id) || (con_id && !ref->con_id) || + (con_id && ref->con_id && strcmp(con_id, ref->con_id) != 0)) + continue; + /* We've already done that on a previous request. */ if (ref->lookup) return 0; diff --git a/drivers/gpio/gpiolib-shared.h b/drivers/gpio/gpiolib-shared.h index 667dbdff3585..40568ef7364c 100644 --- a/drivers/gpio/gpiolib-shared.h +++ b/drivers/gpio/gpiolib-shared.h @@ -16,7 +16,8 @@ struct device; int gpio_device_setup_shared(struct gpio_device *gdev); void gpio_device_teardown_shared(struct gpio_device *gdev); -int gpio_shared_add_proxy_lookup(struct device *consumer, unsigned long lflags); +int gpio_shared_add_proxy_lookup(struct device *consumer, const char *con_id, + unsigned long lflags); #else @@ -28,6 +29,7 @@ static inline int gpio_device_setup_shared(struct gpio_device *gdev) static inline void gpio_device_teardown_shared(struct gpio_device *gdev) { } static inline int gpio_shared_add_proxy_lookup(struct device *consumer, + const char *con_id, unsigned long lflags) { return 0; diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 6d583b3b07bb..9ccfb7af67cc 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -4717,7 +4717,8 @@ struct gpio_desc *gpiod_find_and_request(struct device *consumer, * lookup table for the proxy device as previously * we only knew the consumer's fwnode. */ - ret = gpio_shared_add_proxy_lookup(consumer, lookupflags); + ret = gpio_shared_add_proxy_lookup(consumer, con_id, + lookupflags); if (ret) return ERR_PTR(ret); |