diff options
| author | Johan Hovold <johan@kernel.org> | 2015-01-12 17:12:25 +0100 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2015-01-14 14:24:29 +0100 |
| commit | 225fce83cb72e1bffb712a33ce47c210c770f8ab (patch) | |
| tree | ff753de5fbb156b1990dc83782a195d8ec5cc081 /drivers/gpio | |
| parent | 5539b3c938d64a60cb1fc442ac3ce9263d52de0c (diff) | |
| download | linux-225fce83cb72e1bffb712a33ce47c210c770f8ab.tar.bz2 | |
gpio: fix gpio-chip list corruption
Fix potential corruption of gpio-chip list due to failure to remove the
chip from the list before returning in gpiochip_add error path.
The chip could be long gone when the global list is next traversed,
something which could lead to a null-pointer dereference. In the best
case (chip not deallocated) we are just leaking the gpio range.
Fixes: 14e85c0e69d5 ("gpio: remove gpio_descs global array")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 89c59f5f1924..ac5944b4e4d8 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -248,7 +248,8 @@ int gpiochip_add(struct gpio_chip *chip) base = gpiochip_find_base(chip->ngpio); if (base < 0) { status = base; - goto unlock; + spin_unlock_irqrestore(&gpio_lock, flags); + goto err_free_descs; } chip->base = base; } @@ -288,11 +289,8 @@ int gpiochip_add(struct gpio_chip *chip) acpi_gpiochip_add(chip); status = gpiochip_export(chip); - if (status) { - acpi_gpiochip_remove(chip); - of_gpiochip_remove(chip); - goto fail; - } + if (status) + goto err_remove_chip; pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, chip->base, chip->base + chip->ngpio - 1, @@ -300,9 +298,14 @@ int gpiochip_add(struct gpio_chip *chip) return 0; -unlock: +err_remove_chip: + acpi_gpiochip_remove(chip); + of_gpiochip_remove(chip); + spin_lock_irqsave(&gpio_lock, flags); + list_del(&chip->list); spin_unlock_irqrestore(&gpio_lock, flags); fail: +err_free_descs: kfree(descs); chip->desc = NULL; |