The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 51b00d8509dc69c98740da2ad07308b630d3eb7d Mon Sep 17 00:00:00 2001

From: Zhenyu Wang zhenyuw@linux.intel.com Date: Fri, 11 Jan 2019 13:58:53 +0800 Subject: [PATCH] drm/i915/gvt: Fix mmap range check

This is to fix missed mmap range check on vGPU bar2 region and only allow to map vGPU allocated GMADDR range, which means user space should support sparse mmap to get proper offset for mmap vGPU aperture. And this takes care of actual pgoff in mmap request as original code always does from beginning of vGPU aperture.

Fixes: 659643f7d814 ("drm/i915/gvt/kvmgt: add vfio/mdev support to KVMGT") Cc: "Monroy, Rodrigo Axel" rodrigo.axel.monroy@intel.com Cc: "Orrala Contreras, Alfredo" alfredo.orrala.contreras@intel.com Cc: stable@vger.kernel.org # v4.10+ Reviewed-by: Hang Yuan hang.yuan@intel.com Signed-off-by: Zhenyu Wang zhenyuw@linux.intel.com

diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index a3ee6b7c3cfc..dd3dfd00f4e6 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -996,7 +996,7 @@ static int intel_vgpu_mmap(struct mdev_device *mdev, struct vm_area_struct *vma) { unsigned int index; u64 virtaddr; - unsigned long req_size, pgoff = 0; + unsigned long req_size, pgoff, req_start; pgprot_t pg_prot; struct intel_vgpu *vgpu = mdev_get_drvdata(mdev);

@@ -1014,7 +1014,17 @@ static int intel_vgpu_mmap(struct mdev_device *mdev, struct vm_area_struct *vma) pg_prot = vma->vm_page_prot; virtaddr = vma->vm_start; req_size = vma->vm_end - vma->vm_start; - pgoff = vgpu_aperture_pa_base(vgpu) >> PAGE_SHIFT; + pgoff = vma->vm_pgoff & + ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1); + req_start = pgoff << PAGE_SHIFT; + + if (!intel_vgpu_in_aperture(vgpu, req_start)) + return -EINVAL; + if (req_start + req_size > + vgpu_aperture_offset(vgpu) + vgpu_aperture_sz(vgpu)) + return -EINVAL; + + pgoff = (gvt_aperture_pa_base(vgpu->gvt) >> PAGE_SHIFT) + pgoff;

return remap_pfn_range(vma, virtaddr, pgoff, req_size, pg_prot); }