diff options
| author | Kent Gibson <warthog618@gmail.com> | 2024-04-04 11:33:28 +0200 |
|---|---|---|
| committer | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2024-04-04 18:57:08 +0200 |
| commit | 83092341e15d0dfee1caa8dc502f66c815ccd78a (patch) | |
| tree | 25798b039981a6e2897c624509d19e399e9bd988 | |
| parent | b3b95964590a3d756d69ea8604c856de805479ad (diff) | |
| download | linux-83092341e15d0dfee1caa8dc502f66c815ccd78a.tar.gz | |
gpio: cdev: fix missed label sanitizing in debounce_setup()
When adding sanitization of the label, the path through
edge_detector_setup() that leads to debounce_setup() was overlooked.
A request taking this path does not allocate a new label and the
request label is freed twice when the request is released, resulting
in memory corruption.
Add label sanitization to debounce_setup().
Cc: stable@vger.kernel.org
Fixes: b34490879baa ("gpio: cdev: sanitize the label before requesting the interrupt")
Signed-off-by: Kent Gibson <warthog618@gmail.com>
[Bartosz: rebased on top of the fix for empty GPIO labels]
Co-developed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
| -rw-r--r-- | drivers/gpio/gpiolib-cdev.c | 49 |
1 files changed, 28 insertions, 21 deletions
diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index 1426cc1c4a2858..d09c7d72836551 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -728,6 +728,25 @@ static u32 line_event_id(int level) GPIO_V2_LINE_EVENT_FALLING_EDGE; } +static inline char *make_irq_label(const char *orig) +{ + char *new; + + if (!orig) + return NULL; + + new = kstrdup_and_replace(orig, '/', ':', GFP_KERNEL); + if (!new) + return ERR_PTR(-ENOMEM); + + return new; +} + +static inline void free_irq_label(const char *label) +{ + kfree(label); +} + #ifdef CONFIG_HTE static enum hte_return process_hw_ts_thread(void *p) @@ -1015,6 +1034,7 @@ static int debounce_setup(struct line *line, unsigned int debounce_period_us) { unsigned long irqflags; int ret, level, irq; + char *label; /* try hardware */ ret = gpiod_set_debounce(line->desc, debounce_period_us); @@ -1037,11 +1057,17 @@ static int debounce_setup(struct line *line, unsigned int debounce_period_us) if (irq < 0) return -ENXIO; + label = make_irq_label(line->req->label); + if (IS_ERR(label)) + return -ENOMEM; + irqflags = IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING; ret = request_irq(irq, debounce_irq_handler, irqflags, - line->req->label, line); - if (ret) + label, line); + if (ret) { + free_irq_label(label); return ret; + } line->irq = irq; } else { ret = hte_edge_setup(line, GPIO_V2_LINE_FLAG_EDGE_BOTH); @@ -1083,25 +1109,6 @@ static u32 gpio_v2_line_config_debounce_period(struct gpio_v2_line_config *lc, return 0; } -static inline char *make_irq_label(const char *orig) -{ - char *new; - - if (!orig) - return NULL; - - new = kstrdup_and_replace(orig, '/', ':', GFP_KERNEL); - if (!new) - return ERR_PTR(-ENOMEM); - - return new; -} - -static inline void free_irq_label(const char *label) -{ - kfree(label); -} - static void edge_detector_stop(struct line *line) { if (line->irq) { |