6.8-stable review patch. If anyone has any objections, please let me know.
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From: Kent Gibson warthog618@gmail.com
commit 83092341e15d0dfee1caa8dc502f66c815ccd78a upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpio/gpiolib-cdev.c | 49 +++++++++++++++++++++++++------------------- 1 file changed, 28 insertions(+), 21 deletions(-)
--- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -734,6 +734,25 @@ 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) @@ -1021,6 +1040,7 @@ static int debounce_setup(struct line *l { unsigned long irqflags; int ret, level, irq; + char *label;
/* try hardware */ ret = gpiod_set_debounce(line->desc, debounce_period_us); @@ -1043,11 +1063,17 @@ static int debounce_setup(struct line *l 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); @@ -1089,25 +1115,6 @@ static u32 gpio_v2_line_config_debounce_ 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) {