3.2-stable review patch. If anyone has any objections, please let me know.
------------------ From: Xi Wang <[email protected]> commit 44afb3a04391a74309d16180d1e4f8386fdfa745 upstream. On 32-bit systems, a large args->num_cliprects from userspace via ioctl may overflow the allocation size, leading to out-of-bounds access. This vulnerability was introduced in commit 432e58ed ("drm/i915: Avoid allocation for execbuffer object list"). Signed-off-by: Xi Wang <[email protected]> Reviewed-by: Chris Wilson <[email protected]> Signed-off-by: Daniel Vetter <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 7c50e58..de43194 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -1133,6 +1133,11 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data, return -EINVAL; } + if (args->num_cliprects > UINT_MAX / sizeof(*cliprects)) { + DRM_DEBUG("execbuf with %u cliprects\n", + args->num_cliprects); + return -EINVAL; + } cliprects = kmalloc(args->num_cliprects * sizeof(*cliprects), GFP_KERNEL); if (cliprects == NULL) { -- 1.7.10 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
