From a3f0e598fe4f078507e346e3cdb9beddc147a1f8 Mon Sep 17 00:00:00 2001
Message-Id: <a3f0e598fe4f078507e346e3cdb9beddc147a1f8.1335957620.git.minovotn@redhat.com>
From: Gleb Natapov <gleb@redhat.com>
Date: Tue, 24 Apr 2012 09:24:41 +0200
Subject: [PATCH] fix l1_map buffer overflow

RH-Author: Gleb Natapov <gleb@redhat.com>
Message-id: <20120424092441.GR15413@redhat.com>
Patchwork-id: 39419
O-Subject: [PATCH rhel5.9 rhel5.8.z] fix l1_map buffer overflow
Bugzilla: 814096
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>
RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
RH-Acked-by: Avi Kivity <avi@redhat.com>

l1_map[] array is L1_SIZE long. If index equals L2_SIZE * L1_SIZE then
index >> L2_BITS will point beyond l1_map[].

Credit goes to Ulrich Obergfell for finding the bug.

BZ: 814096
Upstream: Not needed. The code is rewritten.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
--
			Gleb.

Signed-off-by: Michal Novotny <minovotn@redhat.com>
---
 qemu/exec.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/qemu/exec.c b/qemu/exec.c
index 2b621b4..75260c5 100644
--- a/qemu/exec.c
+++ b/qemu/exec.c
@@ -296,7 +296,7 @@ static inline PageDesc **page_l1_map(target_ulong index)
 #if TARGET_LONG_BITS > 32
     /* Host memory outside guest VM.  For 32-bit targets we have already
        excluded high addresses.  */
-    if (index > ((target_ulong)L2_SIZE * L1_SIZE))
+    if (index >= ((target_ulong)L2_SIZE * L1_SIZE))
         return NULL;
 #endif
     return &l1_map[index >> L2_BITS];
-- 
1.7.7.6