QEMU is a FAST! processor emulator
CentOS Sources
2015-05-13 1200d749bf2982b6ba05fe0450503e1980eec129
import qemu-kvm-1.5.3-86.el7_1.2
1 files added
1 files modified
95 ■■■■■ changed files
SOURCES/kvm-fdc-force-the-fifo-access-to-be-in-bounds-of-the-all.patch 85 ●●●●● patch | view | raw | blame | history
SPECS/qemu-kvm.spec 10 ●●●●● patch | view | raw | blame | history
SOURCES/kvm-fdc-force-the-fifo-access-to-be-in-bounds-of-the-all.patch
New file
@@ -0,0 +1,85 @@
From e3b51a8b94859d175b4733d3c17a960934f5edc6 Mon Sep 17 00:00:00 2001
From: Miroslav Rezanina <mrezanin@redhat.com>
Date: Fri, 8 May 2015 17:40:22 +0200
Subject: [PATCH] fdc: force the fifo access to be in bounds of the allocated
 buffer
Bugzilla: 1219269
During processing of certain commands such as FD_CMD_READ_ID and
FD_CMD_DRIVE_SPECIFICATION_COMMAND the fifo memory access could
get out of bounds leading to memory corruption with values coming
from the guest.
Fix this by making sure that the index is always bounded by the
allocated memory.
This is CVE-2015-3456.
Signed-off-by: Petr Matousek <pmatouse@redhat.com>
---
 hw/block/fdc.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/hw/block/fdc.c b/hw/block/fdc.c
index 322d863..56aedcc 100644
--- a/hw/block/fdc.c
+++ b/hw/block/fdc.c
@@ -1434,7 +1434,7 @@ static uint32_t fdctrl_read_data(FDCtrl *fdctrl)
 {
     FDrive *cur_drv;
     uint32_t retval = 0;
-    int pos;
+    uint32_t pos;
     cur_drv = get_cur_drv(fdctrl);
     fdctrl->dsr &= ~FD_DSR_PWRDOWN;
@@ -1443,8 +1443,8 @@ static uint32_t fdctrl_read_data(FDCtrl *fdctrl)
         return 0;
     }
     pos = fdctrl->data_pos;
+    pos %= FD_SECTOR_LEN;
     if (fdctrl->msr & FD_MSR_NONDMA) {
-        pos %= FD_SECTOR_LEN;
         if (pos == 0) {
             if (fdctrl->data_pos != 0)
                 if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv)) {
@@ -1788,10 +1788,13 @@ static void fdctrl_handle_option(FDCtrl *fdctrl, int direction)
 static void fdctrl_handle_drive_specification_command(FDCtrl *fdctrl, int direction)
 {
     FDrive *cur_drv = get_cur_drv(fdctrl);
+    uint32_t pos;
-    if (fdctrl->fifo[fdctrl->data_pos - 1] & 0x80) {
+    pos = fdctrl->data_pos - 1;
+    pos %= FD_SECTOR_LEN;
+    if (fdctrl->fifo[pos] & 0x80) {
         /* Command parameters done */
-        if (fdctrl->fifo[fdctrl->data_pos - 1] & 0x40) {
+        if (fdctrl->fifo[pos] & 0x40) {
             fdctrl->fifo[0] = fdctrl->fifo[1];
             fdctrl->fifo[2] = 0;
             fdctrl->fifo[3] = 0;
@@ -1891,7 +1894,7 @@ static uint8_t command_to_handler[256];
 static void fdctrl_write_data(FDCtrl *fdctrl, uint32_t value)
 {
     FDrive *cur_drv;
-    int pos;
+    uint32_t pos;
     /* Reset mode */
     if (!(fdctrl->dor & FD_DOR_nRESET)) {
@@ -1939,7 +1942,9 @@ static void fdctrl_write_data(FDCtrl *fdctrl, uint32_t value)
     }
     FLOPPY_DPRINTF("%s: %02x\n", __func__, value);
-    fdctrl->fifo[fdctrl->data_pos++] = value;
+    pos = fdctrl->data_pos++;
+    pos %= FD_SECTOR_LEN;
+    fdctrl->fifo[pos] = value;
     if (fdctrl->data_pos == fdctrl->data_len) {
         /* We now have all parameters
          * and will be able to treat the command
--
1.8.3.1
SPECS/qemu-kvm.spec
@@ -69,7 +69,7 @@
Summary: QEMU is a FAST! processor emulator
Name: %{pkgname}%{?pkgsuffix}
Version: 1.5.3
Release: 86%{?dist}.1
Release: 86%{?dist}.2
# Epoch because we pushed a qemu-1.0 package. AIUI this can't ever be dropped
Epoch: 10
License: GPLv2+ and LGPLv2+ and BSD
@@ -2830,6 +2830,8 @@
Patch1391: kvm-cirrus-don-t-overflow-CirrusVGAState-cirrus_bltbuf.patch
# For bz#1198958 - Add rhel-6.6.0 machine type to RHEL 7.1.z to support RHEL 6.6 to RHEL 7.1 live migration
Patch1392: kvm-pc-add-rhel6.6.0-machine-type.patch
# For bz#1219269 - EMBARGOED CVE-2015-3456 qemu-kvm: qemu: floppy disk controller flaw [rhel-7.1.z]
Patch1393: kvm-fdc-force-the-fifo-access-to-be-in-bounds-of-the-all.patch
BuildRequires: zlib-devel
@@ -4430,6 +4432,7 @@
%patch1390 -p1
%patch1391 -p1
%patch1392 -p1
%patch1393 -p1
%build
buildarch="%{kvm_target}-softmmu"
@@ -4874,6 +4877,11 @@
%{_libdir}/pkgconfig/libcacard.pc
%changelog
* Fri May 08 2015 Miroslav Rezanina <mrezanin@redhat.com> - 1.5.3-86.el7_1.2
- kvm-fdc-force-the-fifo-access-to-be-in-bounds-of-the-all.patch [bz#1219269]
- Resolves: bz#1219269
  (EMBARGOED CVE-2015-3456 qemu-kvm: qemu: floppy disk controller flaw [rhel-7.1.z])
* Thu Mar 05 2015 Miroslav Rezanina <mrezanin@redhat.com> - 1.5.3-86.el7_1.1
- kvm-pc-add-rhel6.6.0-machine-type.patch [bz#1198958]
- Resolves: bz#1198958