queue-4.9/media-v4l2-ctrls.c-uvc-zero-v4l2_event.patch

   1 From f45f3f753b0a3d739acda8e311b4f744d82dc52a Mon Sep 17 00:00:00 2001
   2 From: Hans Verkuil <hverkuil@xs4all.nl>
   3 Date: Tue, 18 Dec 2018 08:37:08 -0500
   4 Subject: media: v4l2-ctrls.c/uvc: zero v4l2_event
   5
   6 From: Hans Verkuil <hverkuil@xs4all.nl>
   7
   8 commit f45f3f753b0a3d739acda8e311b4f744d82dc52a upstream.
   9
  10 Control events can leak kernel memory since they do not fully zero the
  11 event. The same code is present in both v4l2-ctrls.c and uvc_ctrl.c, so
  12 fix both.
  13
  14 It appears that all other event code is properly zeroing the structure,
  15 it's these two places.
  16
  17 Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
  18 Reported-by: syzbot+4f021cf3697781dbd9fb@syzkaller.appspotmail.com
  19 Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
  20 Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
  21 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  22
  23 ---
  24  drivers/media/usb/uvc/uvc_ctrl.c     |    2 +-
  25  drivers/media/v4l2-core/v4l2-ctrls.c |    2 +-
  26  2 files changed, 2 insertions(+), 2 deletions(-)
  27
  28 --- a/drivers/media/usb/uvc/uvc_ctrl.c
  29 +++ b/drivers/media/usb/uvc/uvc_ctrl.c
  30 @@ -1203,7 +1203,7 @@ static void uvc_ctrl_fill_event(struct u
  31
  32         __uvc_query_v4l2_ctrl(chain, ctrl, mapping, &v4l2_ctrl);
  33
  34 -       memset(ev->reserved, 0, sizeof(ev->reserved));
  35 +       memset(ev, 0, sizeof(*ev));
  36         ev->type = V4L2_EVENT_CTRL;
  37         ev->id = v4l2_ctrl.id;
  38         ev->u.ctrl.value = value;
  39 --- a/drivers/media/v4l2-core/v4l2-ctrls.c
  40 +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
  41 @@ -1231,7 +1231,7 @@ static u32 user_flags(const struct v4l2_
  42
  43  static void fill_event(struct v4l2_event *ev, struct v4l2_ctrl *ctrl, u32 changes)
  44  {
  45 -       memset(ev->reserved, 0, sizeof(ev->reserved));
  46 +       memset(ev, 0, sizeof(*ev));
  47         ev->type = V4L2_EVENT_CTRL;
  48         ev->id = ctrl->id;
  49         ev->u.ctrl.changes = changes;