commit d9429b84af2302b6e28bec3c52710cf67eda3cee
author Prasad J Pandit <pjp@fedoraproject.org> Fri Dec 02 16:46:26 2016 +0530
committer Michael S. Tsirkin <mst@redhat.com> Fri Dec 16 01:14:38 2016 +0200
tree bd2c363db117e20496965501db75c137cf523ffb
parent e10e798c85c2331dab338b6a01835ebde81136e5

i386: amd_iommu: fix MMIO register count and access

IOMMU MMIO registers are divided in two groups by their offsets.
Low offsets(<0x2000) registers are grouped into 'amdvi_mmio_low'
table and higher offsets(>=0x2000) registers are grouped into
'amdvi_mmio_high' table. No of registers in each table is given
by macro 'AMDVI_MMIO_REGS_LOW' and 'AMDVI_MMIO_REGS_HIGH' resp.
Values of these two macros were swapped, resulting in an OOB
access when reading 'amdvi_mmio_high' table. Correct these two
macros. Also read from 'amdvi_mmio_low' table for lower address.

Reported-by: Azureyang <azureyang@tencent.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/i386/amd_iommu.c

diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
index 47b79d9..e0732cc 100644
--- a/hw/i386/amd_iommu.c
+++ b/hw/i386/amd_iommu.c
@@ -562,7 +562,7 @@
         trace_amdvi_mmio_read(amdvi_mmio_high[index], addr, size, addr & ~0x07);
     } else {
         index = index >= AMDVI_MMIO_REGS_LOW ? AMDVI_MMIO_REGS_LOW : index;
-        trace_amdvi_mmio_read(amdvi_mmio_high[index], addr, size, addr & ~0x07);
+        trace_amdvi_mmio_read(amdvi_mmio_low[index], addr, size, addr & ~0x07);
     }
 }