From d9f2d203ab42f099b32ec4580e43eb08b3e4c412 Mon Sep 17 00:00:00 2001 From: Jason Gerecke Date: Mon, 13 Jul 2015 18:03:44 -0700 Subject: [PATCH] HID: wacom: Properly free inputs if 'wacom_allocate_inputs' fails The 'wacom_allocate_inputs' function tries to allocate three input devices: one each for the pen, touch, and pad. The pointers that are returned by the 'wacom_allocate_input' calls are temporarily stored to local variables where they are checked to ensure they're non-null before storing them in the 'wacom_wac' structure. If an allocation fails, the 'wacom_free_inputs' function is called to reclaim the memory. Unfortunately, 'wacom_free_inputs' is called prior to the pointers being copied, so it is not actually able to free anything. This patch has the calls to 'wacom_allocate_input' store the pointer directly in the 'wacom_wac' structure where they can be freed. Also, it replaces the call to 'wacom_free_inputs' with the (more general) 'wacom_clean_inputs' and removes the no-longer-used function. [jkosina@suse.com: modify to resolve conflict with 67e123f ("Delete unnecessary checks")] Signed-off-by: Jason Gerecke Signed-off-by: Jiri Kosina --- drivers/hid/wacom_sys.c | 52 ++++++++++++++--------------------------- 1 file changed, 18 insertions(+), 34 deletions(-) diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c index 936ad7770ec3..3512d833cc24 100644 --- a/drivers/hid/wacom_sys.c +++ b/drivers/hid/wacom_sys.c @@ -1145,40 +1145,6 @@ static struct input_dev *wacom_allocate_input(struct wacom *wacom) return input_dev; } -static void wacom_free_inputs(struct wacom *wacom) -{ - struct wacom_wac *wacom_wac = &(wacom->wacom_wac); - - input_free_device(wacom_wac->pen_input); - input_free_device(wacom_wac->touch_input); - input_free_device(wacom_wac->pad_input); - wacom_wac->pen_input = NULL; - wacom_wac->touch_input = NULL; - wacom_wac->pad_input = NULL; -} - -static int wacom_allocate_inputs(struct wacom *wacom) -{ - struct input_dev *pen_input_dev, *touch_input_dev, *pad_input_dev; - struct wacom_wac *wacom_wac = &(wacom->wacom_wac); - - pen_input_dev = wacom_allocate_input(wacom); - touch_input_dev = wacom_allocate_input(wacom); - pad_input_dev = wacom_allocate_input(wacom); - if (!pen_input_dev || !touch_input_dev || !pad_input_dev) { - wacom_free_inputs(wacom); - return -ENOMEM; - } - - wacom_wac->pen_input = pen_input_dev; - wacom_wac->touch_input = touch_input_dev; - wacom_wac->touch_input->name = wacom_wac->touch_name; - wacom_wac->pad_input = pad_input_dev; - wacom_wac->pad_input->name = wacom_wac->pad_name; - - return 0; -} - static void wacom_clean_inputs(struct wacom *wacom) { if (wacom->wacom_wac.pen_input) { @@ -1205,6 +1171,24 @@ static void wacom_clean_inputs(struct wacom *wacom) wacom_destroy_leds(wacom); } +static int wacom_allocate_inputs(struct wacom *wacom) +{ + struct wacom_wac *wacom_wac = &(wacom->wacom_wac); + + wacom_wac->pen_input = wacom_allocate_input(wacom); + wacom_wac->touch_input = wacom_allocate_input(wacom); + wacom_wac->pad_input = wacom_allocate_input(wacom); + if (!wacom_wac->pen_input || !wacom_wac->touch_input || !wacom_wac->pad_input) { + wacom_clean_inputs(wacom); + return -ENOMEM; + } + + wacom_wac->touch_input->name = wacom_wac->touch_name; + wacom_wac->pad_input->name = wacom_wac->pad_name; + + return 0; +} + static int wacom_register_inputs(struct wacom *wacom) { struct input_dev *pen_input_dev, *touch_input_dev, *pad_input_dev;