From 2568f83bcc5c4b8aeb149be2c5fc5a743812f0fe Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Sun, 25 Oct 2015 10:34:13 +0100 Subject: [PATCH] Input: uinput - rework ABS validation Rework the uinput ABS validation to check passed absinfo data immediately, but do ABS initialization as last step in UI_DEV_CREATE. The behavior observed by user-space is not changed, as ABS initialization was never checked for errors. With this in place, the order of device-initialization and abs-configuration is no longer fixed. User-space can initialize the device and afterwards set absinfo just fine. Signed-off-by: David Herrmann --- drivers/input/misc/uinput.c | 89 +++++++++++++++++++++++---------------------- 1 file changed, 45 insertions(+), 44 deletions(-) diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c index baac903..1d93037 100644 --- a/drivers/input/misc/uinput.c +++ b/drivers/input/misc/uinput.c @@ -256,13 +256,22 @@ static void uinput_destroy_device(...) static int uinput_create_device(struct uinput_device *udev) { struct input_dev *dev = udev->dev; - int error; + int error, nslot; if (udev->state != UIST_SETUP_COMPLETE) { printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME); return -EINVAL; } + if (test_bit(ABS_MT_SLOT, dev->absbit)) { + nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1; + error = input_mt_init_slots(dev, nslot, 0); + if (error) + goto fail1; + } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) { + input_set_events_per_packet(dev, 60); + } + if (udev->ff_effects_max) { error = input_ff_create(dev, udev->ff_effects_max); if (error) @@ -308,10 +317,35 @@ static int uinput_open(...) return 0; } +static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code, + const struct input_absinfo *abs) +{ + int min, max; + + min = abs->minimum; + max = abs->maximum; + + if ((min != 0 || max != 0) && max <= min) { + printk(KERN_DEBUG + "%s: invalid abs[%02x] min:%d max:%d\n", + UINPUT_NAME, code, min, max); + return -EINVAL; + } + + if (abs->flat > max - min) { + printk(KERN_DEBUG + "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n", + UINPUT_NAME, code, abs->flat, min, max); + return -EINVAL; + } + + return 0; +} + static int uinput_validate_absbits(struct input_dev *dev) { unsigned int cnt; - int nslot; + int error; if (!test_bit(EV_ABS, dev->evbit)) return 0; @@ -321,38 +355,12 @@ static int uinput_validate_absbits(struct input_dev *dev) */ for_each_set_bit(cnt, dev->absbit, ABS_CNT) { - int min, max; - - min = input_abs_get_min(dev, cnt); - max = input_abs_get_max(dev, cnt); - - if ((min != 0 || max != 0) && max <= min) { - printk(KERN_DEBUG - "%s: invalid abs[%02x] min:%d max:%d\n", - UINPUT_NAME, cnt, - input_abs_get_min(dev, cnt), - input_abs_get_max(dev, cnt)); + if (!dev->absinfo) return -EINVAL; - } - - if (input_abs_get_flat(dev, cnt) > - input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) { - printk(KERN_DEBUG - "%s: abs_flat #%02x out of range: %d " - "(min:%d/max:%d)\n", - UINPUT_NAME, cnt, - input_abs_get_flat(dev, cnt), - input_abs_get_min(dev, cnt), - input_abs_get_max(dev, cnt)); - return -EINVAL; - } - } - if (test_bit(ABS_MT_SLOT, dev->absbit)) { - nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1; - input_mt_init_slots(dev, nslot, 0); - } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) { - input_set_events_per_packet(dev, 60); + error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]); + if (error) + return error; } return 0; @@ -375,7 +383,6 @@ static int uinput_dev_setup(struct uinput_device *udev, { struct uinput_setup setup; struct input_dev *dev; - int retval; if (udev->state == UIST_CREATED) return -EINVAL; @@ -393,10 +400,6 @@ static int uinput_dev_setup(struct uinput_device *udev, if (!dev->name) return -ENOMEM; - retval = uinput_validate_absbits(dev); - if (retval < 0) - return retval; - udev->state = UIST_SETUP_COMPLETE; return 0; } @@ -406,6 +409,7 @@ static int uinput_abs_setup(struct uinput_device *udev, { struct uinput_abs_setup setup = {}; struct input_dev *dev; + int error; if (size > sizeof(setup)) return -E2BIG; @@ -418,19 +422,16 @@ static int uinput_abs_setup(struct uinput_device *udev, dev = udev->dev; + error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo); + if (error) + return error; + input_alloc_absinfo(dev); if (!dev->absinfo) return -ENOMEM; set_bit(setup.code, dev->absbit); dev->absinfo[setup.code] = setup.absinfo; - - /* - * We restore the state to UIST_NEW_DEVICE because the user has to call - * UI_DEV_SETUP in the last place before UI_DEV_CREATE to check the - * validity of the absbits. - */ - udev->state = UIST_NEW_DEVICE; return 0; } -- 2.6.1