+ net-can-use-memdup_user.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     net/can: use memdup_user
has been added to the -mm tree.  Its filename is
     net-can-use-memdup_user.patch

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See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this

The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/

------------------------------------------------------
Subject: net/can: use memdup_user
From: Julia Lawall <julia@diku.dk>

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>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Urs Thuermann <urs.thuermann@volkswagen.de>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 net/can/raw.c |   11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff -puN net/can/raw.c~net-can-use-memdup_user net/can/raw.c
--- a/net/can/raw.c~net-can-use-memdup_user
+++ a/net/can/raw.c
@@ -436,14 +436,9 @@ static int raw_setsockopt(struct socket 
 
 		if (count > 1) {
 			/* filter does not fit into dfilter => alloc space */
-			filter = kmalloc(optlen, GFP_KERNEL);
-			if (!filter)
-				return -ENOMEM;
-
-			if (copy_from_user(filter, optval, optlen)) {
-				kfree(filter);
-				return -EFAULT;
-			}
+			filter = memdup_user(optval, optlen);
+			if (IS_ERR(filter))
+				return PTR_ERR(filter);
 		} else if (count == 1) {
 			if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
 				return -EFAULT;
_

Patches currently in -mm which might be from julia@diku.dk are

origin.patch
linux-next.patch
drivers-scsi-aacraid-eliminate-use-after-free.patch
arch-x86-pci-use-kasprintf.patch
drivers-scsi-libsas-use-sam_good.patch
drivers-scsi-remove-unnecessary-null-test.patch
drivers-message-move-dereference-after-null-test.patch
drivers-scsi-correct-the-size-argument-to-kmalloc.patch
drivers-char-ppdevc-use-kasprintf.patch
net-can-use-memdup_user.patch
drivers-net-use-memdup_user.patch
fs-btrfs-use-memdup_user.patch
drivers-video-via-use-memdup_user.patch
mm-use-memdup_user.patch
drivers-net-cxgb3-use-memdup_user.patch
drivers-net-wan-use-memdup_user.patch
drivers-block-use-memdup_user.patch
drivers-media-use-memdup_user.patch
drivers-infiniband-core-use-memdup_user.patch
drivers-i2c-use-memdup_user.patch
drivers-ieee1394-use-memdup_user.patch
fs-autofs4-use-memdup_user.patch
drivers-scsi-use-memdup_user.patch
drivers-char-applicomc-use-memdup_user.patch
drivers-char-vtc-use-memdup_user.patch
drivers-message-i2o-i2o_configc-use-memdup_user.patch
drivers-telephony-ixjc-use-memdup_user.patch
drivers-s390-net-use-memdup_user.patch
drivers-ide-use-memdup_user.patch
net-dccp-use-memdup_user.patch
drivers-net-wireless-prism54-use-memdup_user.patch
drivers-usb-gadget-use-memdup_user.patch
drivers-isdn-use-memdup_user.patch
drivers-staging-dream-camera-use-memdup_user.patch