From 8358e53013fc62c9556598ad842d233906de00ef Mon Sep 17 00:00:00 2001
From: Laszlo Ersek <lersek@redhat.com>
Date: Wed, 24 Oct 2018 21:03:44 +0200
Subject: [PATCH 3/4] IntelFrameworkModulePkg: Add more checker in
 UefiTianoDecompressLib (CVE FIX)

Message-id: <20181024190345.15288-4-lersek@redhat.com>
Patchwork-id: 82885
O-Subject:  [RHEL8 edk2 PATCH 3/4] IntelFrameworkModulePkg: Add more checker in
	UefiTianoDecompressLib (CVE FIX)
Bugzilla: 1641453
1641464
1641469
Acked-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Thomas Huth <thuth@redhat.com>

From: Liming Gao <liming.gao@intel.com>

--v-- RHEL8 note start --v--

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1641453
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1641464
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1641469

Unfortunately, the upstream patch series was not structured according to
the CVE reports. This patch contributes to fixing:

- CVE-2017-5733
- CVE-2017-5734
- CVE-2017-5735

but not CVE-2017-5731 or CVE-2017-5732 (contrarily to the upstream commit
message). The best I could achieve up-stream was to get the "CVE FIX"
expression into the subject, and a whole-sale dump of the CVEs into the
body. I had not been invited to the original (off-list, embargoed)
analysis and review.

The trivial context difference (whitespace) is due to RHEL8 lacking
upstream commit 0a6f48249a60 ("IntelFrameworkModulePkg: Clean up source
files", 2018-06-28). I've considered backporting that (since it only
cleans up whitespace). However, the diffstat on that commit convinced me
otherwise: "246 files changed, 4067 insertions(+), 4067 deletions(-)".
I've decided not to do a partial backport of that (i.e. just for
"BaseUefiTianoCustomDecompressLib.c").

--^-- RHEL8 note end --^--

Fix CVE-2017-5731,CVE-2017-5732,CVE-2017-5733,CVE-2017-5734,CVE-2017-5735
https://bugzilla.tianocore.org/show_bug.cgi?id=686
To make sure the valid buffer be accessed only.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Holtsclaw Brent <brent.holtsclaw@intel.com>
Signed-off-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
(cherry picked from commit 684db6da64bc7b5faee4e1174e801c245f563b5c)
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
---
 .../BaseUefiTianoCustomDecompressLib.c                   | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/IntelFrameworkModulePkg/Library/BaseUefiTianoCustomDecompressLib/BaseUefiTianoCustomDecompressLib.c b/IntelFrameworkModulePkg/Library/BaseUefiTianoCustomDecompressLib/BaseUefiTianoCustomDecompressLib.c
index cb009e7..9b00166 100644
--- a/IntelFrameworkModulePkg/Library/BaseUefiTianoCustomDecompressLib/BaseUefiTianoCustomDecompressLib.c
+++ b/IntelFrameworkModulePkg/Library/BaseUefiTianoCustomDecompressLib/BaseUefiTianoCustomDecompressLib.c
@@ -143,6 +143,7 @@ MakeTable (
   UINT16  Mask;
   UINT16  WordOfStart;
   UINT16  WordOfCount;
+  UINT16  MaxTableLength;
 
   //
   // The maximum mapping table width supported by this internal
@@ -155,6 +156,9 @@ MakeTable (
   }
 
   for (Index = 0; Index < NumOfChar; Index++) {
+    if (BitLen[Index] > 16) {
+      return (UINT16) BAD_TABLE;
+    }
     Count[BitLen[Index]]++;
   }
   
@@ -196,6 +200,7 @@ MakeTable (
 
   Avail = NumOfChar;
   Mask  = (UINT16) (1U << (15 - TableBits));
+  MaxTableLength = (UINT16) (1U << TableBits);
 
   for (Char = 0; Char < NumOfChar; Char++) {
 
@@ -209,6 +214,9 @@ MakeTable (
     if (Len <= TableBits) {
 
       for (Index = Start[Len]; Index < NextCode; Index++) {
+        if (Index >= MaxTableLength) {
+          return (UINT16) BAD_TABLE;
+        }
         Table[Index] = Char;
       }
 
@@ -615,10 +623,14 @@ Decode (
       //
       BytesRemain--;
       while ((INT16) (BytesRemain) >= 0) {
-        Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];
         if (Sd->mOutBuf >= Sd->mOrigSize) {
           goto Done ;
         }
+        if (DataIdx >= Sd->mOrigSize) {
+          Sd->mBadTableFlag = (UINT16) BAD_TABLE;
+          goto Done ;
+        }
+        Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];
 
         BytesRemain--;
       }
@@ -688,7 +700,7 @@ UefiDecompressGetInfo (
   }
 
   CompressedSize   = ReadUnaligned32 ((UINT32 *)Source);
-  if (SourceSize < (CompressedSize + 8)) {
+  if (SourceSize < (CompressedSize + 8) || (CompressedSize + 8) < 8) {
     return RETURN_INVALID_PARAMETER;
   }
 
-- 
1.8.3.1