If user uses wrong ioctl command with _IOC_NONE and argument size greater than 0, it can cause NULL pointer access from memset of line 463. If _IOC_NONE, don't memset to 0 for kdata. Signed-off-by: Zhaowei Yuan <zhaowei.yuan@xxxxxxxxxxx> --- drivers/gpu/drm/drm_drv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) mode change 100644 => 100755 drivers/gpu/drm/drm_drv.c diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c old mode 100644 new mode 100755 index 2ab782c..1a92bcb --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -459,8 +459,9 @@ long drm_ioctl(struct file *filp, retcode = -EFAULT; goto err_i1; } - } else + } else if (cmd & IOC_OUT) { memset(kdata, 0, usize); + } if (ioctl->flags & DRM_UNLOCKED) retcode = func(dev, kdata, file_priv); -- 1.7.9.5 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel