Commit 7ca5ca60 authored May 26, 2010 by Julia Lawall Committed by Linus Torvalds May 27, 2010

fs/autofs4: use memdup_user

Use memdup_user when user data is immediately copied into the allocated
region.  Elimination of the variable ads, which is no longer useful.

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>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent b81d67a5

fs/autofs4/dev-ioctl.c

+2 −11

Original line number	Diff line number	Diff line
		@@ -95,7 +95,7 @@ static int check_dev_ioctl_version(int cmd, struct autofs_dev_ioctl *param)
		*/
		static struct autofs_dev_ioctl copy_dev_ioctl(struct autofs_dev_ioctl __user in)
		{
		struct autofs_dev_ioctl tmp, *ads;
		struct autofs_dev_ioctl tmp;

		if (copy_from_user(&tmp, in, sizeof(tmp)))
		return ERR_PTR(-EFAULT);
		@@ -103,16 +103,7 @@ static struct autofs_dev_ioctl copy_dev_ioctl(struct autofs_dev_ioctl __user i
		if (tmp.size < sizeof(tmp))
		return ERR_PTR(-EINVAL);

		ads = kmalloc(tmp.size, GFP_KERNEL);
		if (!ads)
		return ERR_PTR(-ENOMEM);

		if (copy_from_user(ads, in, tmp.size)) {
		kfree(ads);
		return ERR_PTR(-EFAULT);
		}

		return ads;
		return memdup_user(in, tmp.size);
		}

		static inline void free_dev_ioctl(struct autofs_dev_ioctl *param)