drivers/char/applicom.c: use memdup_user
authorJulia Lawall <julia@diku.dk>
Wed, 26 May 2010 21:43:56 +0000 (14:43 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 27 May 2010 16:12:50 +0000 (09:12 -0700)
Use memdup_user when user data is immediately copied into the
allocated region.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to,size,flag;
position p;
identifier l1,l2;
@@

-  to = \(kmalloc@p\|kzalloc@p\)(size,flag);
+  to = memdup_user(from,size);
   if (
-      to==NULL
+      IS_ERR(to)
                 || ...) {
   <+... when != goto l1;
-  -ENOMEM
+  PTR_ERR(to)
   ...+>
   }
-  if (copy_from_user(to, from, size) != 0) {
-    <+... when != goto l2;
-    -EFAULT
-    ...+>
-  }
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/char/applicom.c

index 63313a3..f4ae0e0 100644 (file)
@@ -703,14 +703,9 @@ static long ac_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
        /* In general, the device is only openable by root anyway, so we're not
           particularly concerned that bogus ioctls can flood the console. */
 
-       adgl = kmalloc(sizeof(struct st_ram_io), GFP_KERNEL);
-       if (!adgl)
-               return -ENOMEM;
-
-       if (copy_from_user(adgl, argp, sizeof(struct st_ram_io))) {
-               kfree(adgl);
-               return -EFAULT;
-       }
+       adgl = memdup_user(argp, sizeof(struct st_ram_io));
+       if (IS_ERR(adgl))
+               return PTR_ERR(adgl);
 
        lock_kernel();  
        IndexCard = adgl->num_card-1;