This Linux kernel change "Input: synaptics-rmi4 – fix possible double free" is included in the Linux 5.1 release. This change is authored by Pan Bian <bianpan2016 [at] 163.com> on Fri Apr 19 07:39:00 2019 +0000. The commit for this change in Linux stable tree is bce1a78 (patch).
Input: synaptics-rmi4 - fix possible double free The RMI4 function structure has been released in rmi_register_function if error occurs. However, it will be released again in the function rmi_create_function, which may result in a double-free bug. Signed-off-by: Pan Bian <[email protected]> Signed-off-by: Dmitry Torokhov <[email protected]>
There are 6 lines of Linux source code added/deleted in this change. Code changes to Linux kernel are as follows.
drivers/input/rmi4/rmi_driver.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/drivers/input/rmi4/rmi_driver.c b/drivers/input/rmi4/rmi_driver.c index fc3ab93..7fb358f 100644 --- a/drivers/input/rmi4/rmi_driver.c +++ b/drivers/input/rmi4/rmi_driver.c @@ -860,7 +860,7 @@ static int rmi_create_function(struct rmi_device *rmi_dev, error = rmi_register_function(fn); if (error) - goto err_put_fn; + return error; if (pdt->function_number == 0x01) data->f01_container = fn; @@ -870,10 +870,6 @@ static int rmi_create_function(struct rmi_device *rmi_dev, list_add_tail(&fn->node, &data->function_list); return RMI_SCAN_CONTINUE; - -err_put_fn: - put_device(&fn->dev); - return error; } void rmi_enable_irq(struct rmi_device *rmi_dev, bool clear_wake)