[3.11.y.z extended stable] Patch "IB/mthca: Return an error on ib_copy_to_udata() failure" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    IB/mthca: Return an error on ib_copy_to_udata() failure

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 141d9504167d46524dd5f6159f4cde406de553e2 Mon Sep 17 00:00:00 2001
From: Yann Droneaud <ydroneaud at opteya.com>
Date: Mon, 10 Mar 2014 23:06:26 +0100
Subject: IB/mthca: Return an error on ib_copy_to_udata() failure

commit 08e74c4b00c30c232d535ff368554959403d0432 upstream.

In case of error when writing to userspace, the function mthca_create_cq()
does not set an error code before following its error path.

This patch sets the error code to -EFAULT when ib_copy_to_udata() fails.

This was caught when using spatch (aka. coccinelle)
to rewrite call to ib_copy_{from,to}_udata().

Link: https://www.gitorious.org/opteya/coccib/source/75ebf2c1033c64c1d81df13e4ae44ee99c989eba:ib_copy_udata.cocci
Link: http://marc.info/?i=cover.1394485254.git.ydroneaud@opteya.com
Signed-off-by: Yann Droneaud <ydroneaud at opteya.com>
Signed-off-by: Roland Dreier <roland at purestorage.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/infiniband/hw/mthca/mthca_provider.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/infiniband/hw/mthca/mthca_provider.c b/drivers/infiniband/hw/mthca/mthca_provider.c
index 5b71d43..42dde06 100644
--- a/drivers/infiniband/hw/mthca/mthca_provider.c
+++ b/drivers/infiniband/hw/mthca/mthca_provider.c
@@ -695,6 +695,7 @@ static struct ib_cq *mthca_create_cq(struct ib_device *ibdev, int entries,

 	if (context && ib_copy_to_udata(udata, &cq->cqn, sizeof (__u32))) {
 		mthca_free_cq(to_mdev(ibdev), cq);
+		err = -EFAULT;
 		goto err_free;
 	}

--
1.9.1