misc: xilinx-sdfec: remove check for ioctl cmd and argument.

if (_IOC_TYPE(cmd) != PP_IOCTL)
        return -ENOTTY;

Invalid ioctl command check normally performs by “default” case.

if (_IOC_DIR(cmd) != _IOC_NONE) {
       argp = (void __user *)arg;
       if (!argp)
             return -EINVAL; }

And for checking ioctl arguments, copy_from_user()/copy_to_user()
checks are enough.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Harshal Chaudhari <harshalchau04@gmail.com>
Link: https://lore.kernel.org/r/20201101170949.18616-1-harshalchau04@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index 6f252793dcebf2f10a8ea9b601aa3946c4934322..23c8448a9c3b79c71d538ac4085dbadf5cf9542f 100644 (file)
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -944,8 +944,8 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
                             unsigned long data)
 {
        struct xsdfec_dev *xsdfec;
-       void __user *arg = NULL;
-       int rval = -EINVAL;
+       void __user *arg = (void __user *)data;
+       int rval;
 
        xsdfec = container_of(fptr->private_data, struct xsdfec_dev, miscdev);
 
@@ -956,16 +956,6 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
                return -EPERM;
        }
 
-       if (_IOC_TYPE(cmd) != XSDFEC_MAGIC)
-               return -ENOTTY;
-
-       /* check if ioctl argument is present and valid */
-       if (_IOC_DIR(cmd) != _IOC_NONE) {
-               arg = (void __user *)data;
-               if (!arg)
-                       return rval;
-       }
-
        switch (cmd) {
        case XSDFEC_START_DEV:
                rval = xsdfec_start(xsdfec);
@@ -1010,7 +1000,7 @@ static long xsdfec_dev_ioctl(struct file *fptr, unsigned int cmd,
                rval = xsdfec_is_active(xsdfec, (bool __user *)arg);
                break;
        default:
-               /* Should not get here */
+               rval = -ENOTTY;
                break;
        }
        return rval;