From 912babd70128d6a4e18d7c4aa0fda7cf0e19f857 Mon Sep 17 00:00:00 2001 From: Zhenyu Wang Date: Wed, 29 May 2019 15:52:00 +0200 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" Cc: "Orrala Contreras, Alfredo" Cc: stable@vger.kernel.org # v4.10+ Reviewed-by: Hang Yuan Signed-off-by: Zhenyu Wang CVE-2019-11085 (cherry picked from commit 51b00d8509dc69c98740da2ad07308b630d3eb7d) Signed-off-by: Timo Aaltonen Acked-by: Kleber Sacilotto de Souza Acked-by: Tyler Hicks Signed-off-by: Kleber Sacilotto de Souza --- drivers/gpu/drm/i915/gvt/kvmgt.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index f6c8fe9824ea..9d36a3c31062 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -819,7 +819,7 @@ 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); @@ -837,7 +837,17 @@ 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); } -- 2.39.5