MdePkg: Add more checker in UefiDecompressLib to access the valid buffer only (CVE...

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

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>

diff --git a/MdePkg/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c b/MdePkg/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c
index dc89157c4efd47c2a1fac61757faf86f754c39a2..9fc637e0582e163eef0c87137a19676cf7915183 100644 (file)
--- a/MdePkg/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c
+++ b/MdePkg/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c
@@ -152,6 +152,7 @@ MakeTable (
   UINT16  Mask;\r
   UINT16  WordOfStart;\r
   UINT16  WordOfCount;\r
+  UINT16  MaxTableLength;\r
 \r
   //\r
   // The maximum mapping table width supported by this internal\r
@@ -164,6 +165,9 @@ MakeTable (
   }\r
 \r
   for (Index = 0; Index < NumOfChar; Index++) {\r
+    if (BitLen[Index] > 16) {\r
+      return (UINT16) BAD_TABLE;\r
+    }\r
     Count[BitLen[Index]]++;\r
   }\r
 \r
@@ -205,6 +209,7 @@ MakeTable (
 \r
   Avail = NumOfChar;\r
   Mask  = (UINT16) (1U << (15 - TableBits));\r
+  MaxTableLength = (UINT16) (1U << TableBits);\r
 \r
   for (Char = 0; Char < NumOfChar; Char++) {\r
 \r
@@ -218,6 +223,9 @@ MakeTable (
     if (Len <= TableBits) {\r
 \r
       for (Index = Start[Len]; Index < NextCode; Index++) {\r
+        if (Index >= MaxTableLength) {\r
+          return (UINT16) BAD_TABLE;\r
+        }\r
         Table[Index] = Char;\r
       }\r
 \r
@@ -620,11 +628,16 @@ Decode (
       // Write BytesRemain of bytes into mDstBase\r
       //\r
       BytesRemain--;\r
+\r
       while ((INT16) (BytesRemain) >= 0) {\r
-        Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];\r
         if (Sd->mOutBuf >= Sd->mOrigSize) {\r
           goto Done;\r
         }\r
+        if (DataIdx >= Sd->mOrigSize) {\r
+          Sd->mBadTableFlag = (UINT16) BAD_TABLE;\r
+          goto Done;\r
+        }\r
+        Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];\r
 \r
         BytesRemain--;\r
       }\r
@@ -694,7 +707,7 @@ UefiDecompressGetInfo (
   }\r
 \r
   CompressedSize   = ReadUnaligned32 ((UINT32 *)Source);\r
-  if (SourceSize < (CompressedSize + 8)) {\r
+  if (SourceSize < (CompressedSize + 8) || (CompressedSize + 8) < 8) {\r
     return RETURN_INVALID_PARAMETER;\r
   }\r
 \r