4.4-stable review patch. If anyone has any objections, please let me know.
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From: Matthew Auld matthew.auld@intel.com
commit c11c7bfd213495784b22ef82a69b6489f8d0092f upstream.
Operating on a zero sized GEM userptr object will lead to explosions.
Fixes: 5cc9ed4b9a7a ("drm/i915: Introduce mapping of user pages into video memory (userptr) ioctl") Testcase: igt/gem_userptr_blits/input-checking Signed-off-by: Matthew Auld matthew.auld@intel.com Cc: Chris Wilson chris@chris-wilson.co.uk Reviewed-by: Chris Wilson chris@chris-wilson.co.uk Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Link: https://patchwork.freedesktop.org/patch/msgid/20180502195021.30900-1-matthew... Cc: Loic hackurx@opensec.fr Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/i915/i915_gem_userptr.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/gpu/drm/i915/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/i915_gem_userptr.c @@ -842,6 +842,9 @@ i915_gem_userptr_ioctl(struct drm_device I915_USERPTR_UNSYNCHRONIZED)) return -EINVAL;
+ if (!args->user_size) + return -EINVAL; + if (offset_in_page(args->user_ptr | args->user_size)) return -EINVAL;