[PATCH 4.1] [media] media/vivid-osd: fix info leak in ioctl

commit eda98796aff0d9bf41094b06811f5def3b4c333c upstream.

The vivid_fb_ioctl() code fails to initialize the 16 _reserved bytes of
struct fb_vblank after the ->hcount member. Add an explicit
memset(0) before filling the structure to avoid the info leak.

This fixes CVE-2015-7884.

Signed-off-by: Salva Peiró <redacted>
Signed-off-by: Hans Verkuil <redacted>
Signed-off-by: Mauro Carvalho Chehab <redacted>
Signed-off-by: Yuki Machida <redacted>
---
 drivers/media/platform/vivid/vivid-osd.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/media/platform/vivid/vivid-osd.c b/drivers/media/platform/vivid/vivid-osd.c
index 084d346..e15eef6 100644
--- a/drivers/media/platform/vivid/vivid-osd.c
+++ b/drivers/media/platform/vivid/vivid-osd.c

@@ -85,6 +85,7 @@ static int vivid_fb_ioctl(struct fb_info *info, unsigned cmd, unsigned long arg)
 	case FBIOGET_VBLANK: {
 		struct fb_vblank vblank;
 
+		memset(&vblank, 0, sizeof(vblank));
 		vblank.flags = FB_VBLANK_HAVE_COUNT | FB_VBLANK_HAVE_VCOUNT |
 			FB_VBLANK_HAVE_VSYNC;
 		vblank.count = 0;

-- 
1.9.1

On Mon, Jan 25, 2016 at 07:42:18PM +0900, Yuki Machida wrote:

commit eda98796aff0d9bf41094b06811f5def3b4c333c upstream.

The vivid_fb_ioctl() code fails to initialize the 16 _reserved bytes of
struct fb_vblank after the ->hcount member. Add an explicit
memset(0) before filling the structure to avoid the info leak.

This fixes CVE-2015-7884.

Signed-off-by: Salva Peiró <redacted>
Signed-off-by: Hans Verkuil <redacted>
Signed-off-by: Mauro Carvalho Chehab <redacted>
Signed-off-by: Yuki Machida <redacted>
---
 drivers/media/platform/vivid/vivid-osd.c | 1 +
 1 file changed, 1 insertion(+)

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read Documentation/stable_kernel_rules.txt
for how to do this properly.

</formletter>

It has sent to the wrong Mainling List.
sorry.

On 2016年01月25日 19:42, Yuki Machida wrote:

Hi Greg,

On 2016年01月26日 02:18, Greg KH wrote:

On Mon, Jan 25, 2016 at 07:42:18PM +0900, Yuki Machida wrote:

quoted

commit eda98796aff0d9bf41094b06811f5def3b4c333c upstream.

The vivid_fb_ioctl() code fails to initialize the 16 _reserved bytes of
struct fb_vblank after the ->hcount member. Add an explicit
memset(0) before filling the structure to avoid the info leak.

This fixes CVE-2015-7884.

Signed-off-by: Salva Peiró <redacted>
Signed-off-by: Hans Verkuil <redacted>
Signed-off-by: Mauro Carvalho Chehab <redacted>
Signed-off-by: Yuki Machida <redacted>
---
  drivers/media/platform/vivid/vivid-osd.c | 1 +
  1 file changed, 1 insertion(+)

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read Documentation/stable_kernel_rules.txt
for how to do this properly.

Thank you for your advice.
I will check stable_kernel_rules.txt again.

</formletter>