File kvm-qemu-preXX-pci-assign-Harden-I-O-port-test.... of Package kvm

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File kvm-qemu-preXX-pci-assign-Harden-I-O-port-test.patch of Package kvm

From 1d1c8a498b7ce5c5636f1014f7ad18aa4e1acc0a Mon Sep 17 00:00:00 2001
From: Alex Williamson <alex.williamson@redhat.com>
Date: Wed, 16 Nov 2011 13:46:45 -0700
Subject: [PATCH] pci-assign: Harden I/O port test

Markus Armbruster points out that we're missing a < 0 check
from pread while trying to probe for pci-sysfs io-port
resource support.  We don't expect a short read, but we
should harden the test to abort if we get one so we're not
potentially looking at a stale errno.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
 hw/device-assignment.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/hw/device-assignment.c b/hw/device-assignment.c
index 0160de7..7e6f972 100644
--- a/hw/device-assignment.c
+++ b/hw/device-assignment.c
@@ -434,8 +434,9 @@ static int assigned_dev_register_regions(PCIRegion *io_regions,
              * kernels return EIO.  New kernels only allow 1/2/4 byte reads
              * so should return EINVAL for a 3 byte read */
             ret = pread(pci_dev->v_addrs[i].region->resource_fd, &val, 3, 0);
-            if (ret == 3) {
-                fprintf(stderr, "I/O port resource supports 3 byte read?!\n");
+            if (ret >= 0) {
+                fprintf(stderr, "Unexpected return from I/O port read: %d\n",
+                        ret);
                 abort();
             } else if (errno != EINVAL) {
                 fprintf(stderr, "Using raw in/out ioport access (sysfs - %s)\n",
-- 
1.7.7

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File kvm-qemu-preXX-pci-assign-Harden-I-O-port-test.patch of Package kvm

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