tier1: fix possible unsafe read in lzss SafeUncompress, make tests pass under asan

This commit is contained in:
nillerusr 2023-04-07 14:56:56 +03:00
parent 4f063c4053
commit 92028d4e80
7 changed files with 115 additions and 25 deletions

View File

@ -1385,7 +1385,7 @@ bool COM_BufferToBufferDecompress( void *dest, unsigned int *destLen, const void
if ( pHeader->id == LZSS_ID )
{
CLZSS s;
int nActualDecompressedSize = s.SafeUncompress( (byte *)source, (byte *)dest, *destLen );
int nActualDecompressedSize = s.SafeUncompress( (byte *)source, sourceLen, (byte *)dest, *destLen );
if ( nActualDecompressedSize != nDecompressedSize )
{
Warning( "NET_BufferToBufferDecompress: header said %d bytes would be decompressed, but we LZSS decompressed %d\n", nDecompressedSize, nActualDecompressedSize );

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@ -915,7 +915,7 @@ CBasePanel::CBasePanel() : Panel(NULL, "BaseGameUIPanel")
}
}
// if( IsAndroid() )
if( IsAndroid() )
{
AddUrlButton( this, "vgui/\x64\x69\x73\x63\x6f\x72\x64\x5f\x6c\x6f\x67\x6f", "\x68\x74\x74\x70\x73\x3a\x2f\x2f\x64\x69\x73\x63\x6f\x72\x64\x2e\x67\x67\x2f\x68\x5a\x52\x42\x37\x57\x4d\x67\x47\x77" );
AddUrlButton( this, "vgui/\x74\x77\x69\x74\x74\x65\x72\x5f\x6c\x6f\x67\x6f", "\x68\x74\x74\x70\x73\x3a\x2f\x2f\x74\x77\x69\x74\x74\x65\x72\x2e\x63\x6f\x6d\x2f\x6e\x69\x6c\x6c\x65\x72\x75\x73\x72" );

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@ -606,6 +606,16 @@ typedef void * HINSTANCE;
#define FMTFUNCTION( a, b )
#endif
#if defined(__has_feature)
#if __has_feature(address_sanitizer)
#define USING_ASAN 1
#endif
#endif
#if !defined( USING_ASAN ) && defined( __SANITIZE_ADDRESS__ )
#define USING_ASAN 1
#endif
#if COMPILER_CLANG || COMPILER_GCC
#define NO_ASAN __attribute__((no_sanitize("address")))
#else

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@ -30,7 +30,7 @@ public:
unsigned char* CompressNoAlloc( const unsigned char *pInput, int inputlen, unsigned char *pOutput, unsigned int *pOutputSize );
unsigned int Uncompress( const unsigned char *pInput, unsigned char *pOutput );
//unsigned int Uncompress( unsigned char *pInput, CUtlBuffer &buf );
unsigned int SafeUncompress( const unsigned char *pInput, unsigned char *pOutput, unsigned int unBufSize );
unsigned int SafeUncompress( const unsigned char *pInput, unsigned int inputSize, unsigned char *pOutput, unsigned int unBufSize );
static bool IsCompressed( const unsigned char *pInput );
static unsigned int GetActualSize( const unsigned char *pInput );

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@ -294,23 +294,21 @@ unsigned int CLZSS::Uncompress( unsigned char *pInput, CUtlBuffer &buf )
}
*/
unsigned int CLZSS::SafeUncompress( const unsigned char *pInput, unsigned char *pOutput, unsigned int unBufSize )
unsigned int CLZSS::SafeUncompress( const unsigned char *pInput, unsigned int inputSize, unsigned char *pOutput, unsigned int unBufSize )
{
unsigned int totalBytes = 0;
int cmdByte = 0;
int getCmdByte = 0;
unsigned int actualSize = GetActualSize( pInput );
if ( !actualSize )
{
// unrecognized
return 0;
}
if ( actualSize > unBufSize )
{
if ( !actualSize ||
actualSize > unBufSize ||
inputSize <= sizeof( lzss_header_t ) )
return 0;
}
const unsigned char *pInputEnd = pInput+inputSize-1;
const unsigned char *pOrigOutput = pOutput;
pInput += sizeof( lzss_header_t );
@ -318,35 +316,39 @@ unsigned int CLZSS::SafeUncompress( const unsigned char *pInput, unsigned char *
{
if ( !getCmdByte )
{
if( pInput > pInputEnd )
return 0;
cmdByte = *pInput++;
}
getCmdByte = ( getCmdByte + 1 ) & 0x07;
if ( cmdByte & 0x01 )
{
if( pInput+1 > pInputEnd )
return 0;
int position = *pInput++ << LZSS_LOOKSHIFT;
position |= ( *pInput >> LZSS_LOOKSHIFT );
int count = ( *pInput++ & 0x0F ) + 1;
if ( count == 1 )
{
break;
}
unsigned char *pSource = pOutput - position - 1;
if ( totalBytes + count > unBufSize )
{
if ( totalBytes + count > unBufSize ||
pSource < pOrigOutput )
return 0;
}
for ( int i=0; i<count; i++ )
{
*pOutput++ = *pSource++;
}
totalBytes += count;
}
else
{
if ( totalBytes + 1 > unBufSize )
if ( totalBytes + 1 > unBufSize ||
pInput > pInputEnd )
return 0;
*pOutput++ = *pInput++;

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@ -0,0 +1,78 @@
#include "tier0/dbg.h"
#include "unitlib/unitlib.h"
#include "tier1/lzss.h"
#ifdef USING_ASAN
#include <sanitizer/asan_interface.h>
#endif
DEFINE_TESTSUITE( LZSSSafeUncompressTestSuite )
static void SafeUncompressTests()
{
CLZSS lzss;
char poision1[8192];
unsigned char in[256];
char poision2[8192];
unsigned char out[256];
char poision3[8192];
#ifdef USING_ASAN
ASAN_POISON_MEMORY_REGION( poision1, 8192 );
ASAN_POISON_MEMORY_REGION( poision2, 8192 );
ASAN_POISON_MEMORY_REGION( poision3, 8192 );
#endif
lzss_header_t *pHeader = (lzss_header_t*)in;
pHeader->actualSize = sizeof(in)-sizeof(lzss_header_t);
pHeader->id = LZSS_ID;
uint result = 0;
// 0xff bytes test
memset(in+8, 0xFF, sizeof(in)-sizeof(lzss_header_t));
result = lzss.SafeUncompress( in, sizeof(in), out, sizeof(out) );
Shipping_Assert( result == 0 );
// zero bytes test
memset(in+8, 0x0, sizeof(in)-sizeof(lzss_header_t));
result = lzss.SafeUncompress( in, sizeof(in), out, sizeof(out) );
Shipping_Assert( result == 0 );
// valid data, invalid header
pHeader->actualSize = 1;
pHeader->id = LZSS_ID;
result = lzss.SafeUncompress( in, sizeof(in), out, sizeof(out) );
Shipping_Assert( result == 0 );
pHeader->actualSize = 999;
pHeader->id = LZSS_ID;
result = lzss.SafeUncompress( in, sizeof(in), out, sizeof(out) );
Shipping_Assert( result == 0 );
pHeader->actualSize = 999;
pHeader->id = 1337;
result = lzss.SafeUncompress( in, sizeof(in), out, sizeof(out) );
Shipping_Assert( result == 0 );
// valid header, valid data
const unsigned char compressed[] = {0x4c,0x5a,0x53,0x53,0x1a,0x0,0x0,0x0,0x0,0x44,0x6f,0x20,0x79,0x6f,0x75,0x20,0x6c,0x0,0x69,0x6b,0x65,0x20,0x77,0x68,0x61,0x74,0x41,0x0,0xd4,0x73,0x65,0x65,0x3f,0x0,0x0,0x0};
pHeader->actualSize = sizeof(compressed);
pHeader->id = LZSS_ID;
result = lzss.SafeUncompress( compressed, sizeof(compressed), out, sizeof(out) );
const char data[] = "Do you like what you see?";
Shipping_Assert( memcmp(out, data, 26) == 0 );
Shipping_Assert( result == 26 );
}
DEFINE_TESTCASE( LZSSSafeUncompressTest, LZSSSafeUncompressTestSuite )
{
Msg( "Running CLZSS::SafeUncompress tests\n" );
SafeUncompressTests();
}

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@ -14,7 +14,7 @@ def configure(conf):
conf.define('TIER1TEST_EXPORTS', 1)
def build(bld):
source = ['commandbuffertest.cpp', 'utlstringtest.cpp', 'tier1test.cpp'] #, 'lzsstest.cpp']
source = ['commandbuffertest.cpp', 'utlstringtest.cpp', 'tier1test.cpp', 'lzsstest.cpp']
includes = ['../../public', '../../public/tier0']
defines = []
libs = ['tier0', 'tier1', 'mathlib', 'unitlib']