[media] v4l: make sure drivers supply a zeroed struct v4l2_subdev

Some v4l drivers currently don't initialize their struct v4l2_subdev
with zeros, and this is a problem since some of the v4l2 code expects
this. One example is the addition of internal_ops in commit 45f6f84,
after that we are at risk of random oopses with these drivers when code
in v4l2_device_register_subdev tries to dereference sd->internal_ops->*,
as can be shown by the report at http://bugs.launchpad.net/bugs/745213
and analysis of its crash at https://lkml.org/lkml/2011/4/1/168

Use kzalloc within problematic drivers to ensure we have a zeroed struct
v4l2_subdev.

BugLink: http://bugs.launchpad.net/bugs/745213
Cc: <stable@kernel.org>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/media/video/m52790.c b/drivers/media/video/m52790.c
index 5e1c9a81984c..303ffa7df4ac 100644
--- a/drivers/media/video/m52790.c
+++ b/drivers/media/video/m52790.c
@@ -174,7 +174,7 @@ static int m52790_probe(struct i2c_client *client,
         v4l_info(client, "chip found @ 0x%x (%s)\n",
                         client->addr << 1, client->adapter->name);
 
-        state = kmalloc(sizeof(struct m52790_state), GFP_KERNEL);
+        state = kzalloc(sizeof(struct m52790_state), GFP_KERNEL);
         if (state == NULL)
                 return -ENOMEM;