From 4dfcc271d587465f0d181c7636453ba4d0ec8acc Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Fri, 11 Feb 2011 01:10:45 -0800 Subject: [PATCH] Input: uinput - use memdup_user() and friends Instead of open-coding copying of data structures from userspace use memdup_user() and strndup_user(). Note that this introduces change in behavior because driver used to truncate 'phys' longer than 1024 bytes, but now it will refuse to set 'phys' that long. Arguably trying to set such 'phys' is suspect anyways. Signed-off-by: Dmitry Torokhov --- drivers/input/misc/uinput.c | 35 ++++++++++------------------------- 1 file changed, 10 insertions(+), 25 deletions(-) diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c index c0888e3d2fb4..7f8331f45bad 100644 --- a/drivers/input/misc/uinput.c +++ b/drivers/input/misc/uinput.c @@ -361,14 +361,9 @@ static int uinput_setup_device(struct uinput_device *udev, const char __user *bu dev = udev->dev; - user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL); - if (!user_dev) - return -ENOMEM; - - if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) { - retval = -EFAULT; - goto exit; - } + user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev)); + if (!IS_ERR(user_dev)) + return PTR_ERR(user_dev); udev->ff_effects_max = user_dev->ff_effects_max; @@ -621,7 +616,6 @@ static long uinput_ioctl_handler(struct file *file, unsigned int cmd, struct uinput_ff_upload ff_up; struct uinput_ff_erase ff_erase; struct uinput_request *req; - int length; char *phys; retval = mutex_lock_interruptible(&udev->mutex); @@ -688,24 +682,15 @@ static long uinput_ioctl_handler(struct file *file, unsigned int cmd, retval = -EINVAL; goto out; } - length = strnlen_user(p, 1024); - if (length <= 0) { - retval = -EFAULT; - break; + + phys = strndup_user(p, 1024); + if (IS_ERR(phys)) { + retval = PTR_ERR(phys); + goto out; } + kfree(udev->dev->phys); - udev->dev->phys = phys = kmalloc(length, GFP_KERNEL); - if (!phys) { - retval = -ENOMEM; - break; - } - if (copy_from_user(phys, p, length)) { - udev->dev->phys = NULL; - kfree(phys); - retval = -EFAULT; - break; - } - phys[length - 1] = '\0'; + udev->dev->phys = phys; break; case UI_BEGIN_FF_UPLOAD: -- 2.30.2