From 4b40893918203ee1a1f6a114316c2a19c072e9bd Mon Sep 17 00:00:00 2001 From: Matthias Hopf Date: Sat, 18 Oct 2008 07:18:05 +1000 Subject: drm/i915: fix ioremap of a user address for non-root (CVE-2008-3831) Olaf Kirch noticed that the i915_set_status_page() function of the i915 kernel driver calls ioremap with an address offset that is supplied by userspace via ioctl. The function zeroes the mapped memory via memset and tells the hardware about the address. Turns out that access to that ioctl is not restricted to root so users could probably exploit that to do nasty things. We haven't tried to write actual exploit code though. It only affects the Intel G33 series and newer. Signed-off-by: Dave Airlie --- drivers/gpu/drm/i915/i915_dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 9b967bf..db34780 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -940,7 +940,7 @@ struct drm_ioctl_desc i915_ioctls[] = { DRM_IOCTL_DEF(DRM_I915_SET_VBLANK_PIPE, i915_vblank_pipe_set, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY ), DRM_IOCTL_DEF(DRM_I915_GET_VBLANK_PIPE, i915_vblank_pipe_get, DRM_AUTH ), DRM_IOCTL_DEF(DRM_I915_VBLANK_SWAP, i915_vblank_swap, DRM_AUTH), - DRM_IOCTL_DEF(DRM_I915_HWS_ADDR, i915_set_status_page, DRM_AUTH), + DRM_IOCTL_DEF(DRM_I915_HWS_ADDR, i915_set_status_page, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_IOCTL_DEF(DRM_I915_GEM_INIT, i915_gem_init_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY), DRM_IOCTL_DEF(DRM_I915_GEM_EXECBUFFER, i915_gem_execbuffer, DRM_AUTH), DRM_IOCTL_DEF(DRM_I915_GEM_PIN, i915_gem_pin_ioctl, DRM_AUTH|DRM_ROOT_ONLY), -- cgit v1.1