viio_trigger_alloc() initializes the device with device_initialize() but uses kfree() directly in error paths, which bypasses the device's release callback iio_trig_release(). This could lead to memory leaks and inconsistent device state.
Additionally, the current error handling has the following issues: 1. Potential double-free of IRQ descriptors when kvasprintf fails. 2. The release function may attempt to free negative subirq_base. 3. Missing mutex_destroy in release function.
Fix these issues by: 1. Replacing kfree(trig) with put_device(&trig->dev) in error paths. 2. Setting subirq_base to 0 after freeing IRQ descriptors in error path to prevent double-free in release callback. 3. Modifying release function to properly handle negative subirq_base. 4. Adding missing mutex_destroy().
Found by code review.
Cc: stable@vger.kernel.org Fixes: 2c99f1a09da3 ("iio: trigger: clean up viio_trigger_alloc()") Signed-off-by: Ma Ke make24@iscas.ac.cn --- Changes in v2: - modified the patch, thanks for developer's suggestions. --- drivers/iio/industrialio-trigger.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c index 54416a384232..9f6d30a244d9 100644 --- a/drivers/iio/industrialio-trigger.c +++ b/drivers/iio/industrialio-trigger.c @@ -524,6 +524,7 @@ static void iio_trig_release(struct device *device) CONFIG_IIO_CONSUMERS_PER_TRIGGER); } kfree(trig->name); + mutex_destroy(&trig->pool_lock); kfree(trig); }
@@ -596,8 +597,9 @@ struct iio_trigger *viio_trigger_alloc(struct device *parent,
free_descs: irq_free_descs(trig->subirq_base, CONFIG_IIO_CONSUMERS_PER_TRIGGER); + trig->subirq_base = 0; free_trig: - kfree(trig); + put_device(&trig->dev); return NULL; }