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- Use MAP_FAILED error code for check whether mmap() was successful

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- Replace various malloc() with Z_Malloc
- Fix several memory leaks when VM compilation failed and Com_Error is called
- Make failed mmap/VirtualAlloc/malloc calls fatal
This commit is contained in:
Thilo Schulz 2011-02-10 18:45:28 +00:00
parent 5e0d0efd2e
commit 544a1c0c1a
5 changed files with 50 additions and 27 deletions
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33
code/qcommon/vm_x86.c
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@ -53,6 +53,7 @@ static void VM_Destroy_Compiled(vm_t* self);
*/
#define VMFREE_BUFFERS() {Z_Free(buf); Z_Free(jused);}
static byte *buf = NULL;
static byte *jused = NULL;
static int compiledOfs = 0;
@ -289,6 +290,7 @@ static int Hex( int c ) {
return c - '0';
}
VMFREE_BUFFERS();
Com_Error( ERR_DROP, "Hex: bad char '%c'", c );
return 0;
@ -408,6 +410,7 @@ qboolean EmitMovEBXEDI(vm_t *vm, int andit) {
#define JUSED(x) \
do { \
if (x < 0 || x >= jusedSize) { \
VMFREE_BUFFERS(); \
Com_Error( ERR_DROP, \
"VM_CompileX86: jump target out of range at offset %d", pc ); \
} \
@ -429,7 +432,7 @@ void VM_Compile( vm_t *vm, vmHeader_t *header ) {
// allocate a very large temp buffer, we will shrink it later
maxLength = header->codeLength * 8;
buf = Z_Malloc( maxLength );
buf = Z_Malloc(maxLength);
jused = Z_Malloc(jusedSize);
Com_Memset(jused, 0, jusedSize);
@ -454,16 +457,21 @@ void VM_Compile( vm_t *vm, vmHeader_t *header ) {
LastCommand = LAST_COMMAND_NONE;
while ( instruction < header->instructionCount ) {
if ( compiledOfs > maxLength - 16 ) {
Com_Error( ERR_FATAL, "VM_CompileX86: maxLength exceeded" );
while(instruction < header->instructionCount)
{
if(compiledOfs > maxLength - 16)
{
VMFREE_BUFFERS();
Com_Error(ERR_DROP, "VM_CompileX86: maxLength exceeded");
}
vm->instructionPointers[ instruction ] = compiledOfs;
instruction++;
if ( pc > header->codeLength ) {
Com_Error( ERR_FATAL, "VM_CompileX86: pc > header->codeLength" );
if(pc > header->codeLength)
{
VMFREE_BUFFERS();
Com_Error(ERR_DROP, "VM_CompileX86: pc > header->codeLength");
}
op = code[ pc ];
@ -1075,7 +1083,8 @@ void VM_Compile( vm_t *vm, vmHeader_t *header ) {
Emit4( (int)vm->instructionPointers );
break;
default:
Com_Error( ERR_DROP, "VM_CompileX86: bad opcode %i at offset %i", op, pc );
VMFREE_BUFFERS();
Com_Error(ERR_DROP, "VM_CompileX86: bad opcode %i at offset %i", op, pc);
}
pop0 = pop1;
pop1 = op;
@ -1086,13 +1095,13 @@ void VM_Compile( vm_t *vm, vmHeader_t *header ) {
vm->codeLength = compiledOfs;
#ifdef VM_X86_MMAP
vm->codeBase = mmap(NULL, compiledOfs, PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, -1, 0);
if(vm->codeBase == (void*)-1)
Com_Error(ERR_DROP, "VM_CompileX86: can't mmap memory");
if(vm->codeBase == MAP_FAILED)
Com_Error(ERR_FATAL, "VM_CompileX86: can't mmap memory");
#elif _WIN32
// allocate memory with EXECUTE permissions under windows.
vm->codeBase = VirtualAlloc(NULL, compiledOfs, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
if(!vm->codeBase)
Com_Error(ERR_DROP, "VM_CompileX86: VirtualAlloc failed");
Com_Error(ERR_FATAL, "VM_CompileX86: VirtualAlloc failed");
#else
vm->codeBase = malloc(compiledOfs);
#endif
@ -1101,14 +1110,14 @@ void VM_Compile( vm_t *vm, vmHeader_t *header ) {
#ifdef VM_X86_MMAP
if(mprotect(vm->codeBase, compiledOfs, PROT_READ|PROT_EXEC))
Com_Error(ERR_DROP, "VM_CompileX86: mprotect failed");
Com_Error(ERR_FATAL, "VM_CompileX86: mprotect failed");
#elif _WIN32
{
DWORD oldProtect = 0;
// remove write permissions.
if(!VirtualProtect(vm->codeBase, compiledOfs, PAGE_EXECUTE_READ, &oldProtect))
Com_Error(ERR_DROP, "VM_CompileX86: VirtualProtect failed");
Com_Error(ERR_FATAL, "VM_CompileX86: VirtualProtect failed");
}
#endif