[RHEL-7.4.z PATCH BZ1739309] drm/i915/gvt: Fix mmap range check

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Bugzilla: 1713567
Z-Bugzilla: 1739309
CVE: CVE-2019-11085
Build Info: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=25302094

This is a backport of 7.6.z patch to 7.4.z - 7.4.z needs
intel_vgpu_in_aperture(), so add it.

7.6.z patch tested: Win10 VM with assigned Intel vGPU still works

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@xxxxxxxxx>
Cc: "Orrala Contreras, Alfredo" <alfredo.orrala.contreras@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.10+
Reviewed-by: Hang Yuan <hang.yuan@xxxxxxxxx>
Signed-off-by: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>
(cherry picked from commit 51b00d8509dc69c98740da2ad07308b630d3eb7d)
Signed-off-by: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
---
 drivers/gpu/drm/i915/gvt/kvmgt.c | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index e466259034e..d2696636f82 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -85,6 +85,12 @@ static inline bool handle_valid(unsigned long handle)
 	return !!(handle & ~0xff);
 }
 
+static inline bool intel_vgpu_in_aperture(struct intel_vgpu *vgpu, uint64_t off)
+{
+	return off >= vgpu_aperture_offset(vgpu) &&
+	       off < vgpu_aperture_offset(vgpu) + vgpu_aperture_sz(vgpu);
+}
+
 static int kvmgt_guest_init(struct mdev_device *mdev);
 static void intel_vgpu_release_work(struct work_struct *work);
 static bool kvmgt_guest_exit(struct kvmgt_guest_info *info);
@@ -803,7 +809,7 @@ 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);
 
@@ -821,7 +827,17 @@ 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);
 }
-- 
2.21.0





[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux