Ekdohibs
/
zig
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ir: Prevent crash when indexing undefined ptr to array 

Closes #4471
master
LemonBoy 2020-02-15 21:17:39 +01:00
parent b15958c557
commit 096f79260b
2 changed files with 35 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

44
src/ir.cpp
View File

@ -20638,12 +20638,12 @@ static IrInstGen *ir_analyze_instruction_elem_ptr(IrAnalyze *ira, IrInstSrcElemP
if (type_is_invalid(array_ptr->value->type))
return ira->codegen->invalid_inst_gen;
ZigValue *orig_array_ptr_val = array_ptr->value;
IrInstGen *elem_index = elem_ptr_instruction->elem_index->child;
if (type_is_invalid(elem_index->value->type))
return ira->codegen->invalid_inst_gen;
ZigValue *orig_array_ptr_val = array_ptr->value;
ZigType *ptr_type = orig_array_ptr_val->type;
assert(ptr_type->id == ZigTypeIdPointer);
@ -20653,23 +20653,25 @@ static IrInstGen *ir_analyze_instruction_elem_ptr(IrAnalyze *ira, IrInstSrcElemP
// We will adjust return_type's alignment before returning it.
ZigType *return_type;
if (type_is_invalid(array_type)) {
if (type_is_invalid(array_type))
return ira->codegen->invalid_inst_gen;
} else if (array_type->id == ZigTypeIdArray ||
(array_type->id == ZigTypeIdPointer &&
array_type->data.pointer.ptr_len == PtrLenSingle &&
array_type->data.pointer.child_type->id == ZigTypeIdArray))
if (array_type->id == ZigTypeIdPointer &&
array_type->data.pointer.ptr_len == PtrLenSingle &&
array_type->data.pointer.child_type->id == ZigTypeIdArray)
{
if (array_type->id == ZigTypeIdPointer) {
array_type = array_type->data.pointer.child_type;
ptr_type = ptr_type->data.pointer.child_type;
if (orig_array_ptr_val->special != ConstValSpecialRuntime) {
orig_array_ptr_val = const_ptr_pointee(ira, ira->codegen, orig_array_ptr_val,
elem_ptr_instruction->base.base.source_node);
if (orig_array_ptr_val == nullptr)
return ira->codegen->invalid_inst_gen;
}
}
IrInstGen *ptr_value = ir_get_deref(ira, &elem_ptr_instruction->base.base,
array_ptr, nullptr);
if (type_is_invalid(ptr_value->value->type))
return ira->codegen->invalid_inst_gen;
array_type = array_type->data.pointer.child_type;
ptr_type = ptr_type->data.pointer.child_type;
orig_array_ptr_val = ptr_value->value;
}
if (array_type->id == ZigTypeIdArray) {
if (array_type->data.array.len == 0) {
ir_add_error_node(ira, elem_ptr_instruction->base.base.source_node,
buf_sprintf("index 0 outside array of size 0"));
@ -20807,8 +20809,14 @@ static IrInstGen *ir_analyze_instruction_elem_ptr(IrAnalyze *ira, IrInstSrcElemP
orig_array_ptr_val->data.x_ptr.special != ConstPtrSpecialHardCodedAddr &&
(orig_array_ptr_val->data.x_ptr.mut != ConstPtrMutRuntimeVar || array_type->id == ZigTypeIdArray))
{
if ((err = ir_resolve_const_val(ira->codegen, ira->new_irb.exec,
elem_ptr_instruction->base.base.source_node, orig_array_ptr_val, UndefBad)))
{
return ira->codegen->invalid_inst_gen;
}
ZigValue *array_ptr_val = const_ptr_pointee(ira, ira->codegen, orig_array_ptr_val,
elem_ptr_instruction->base.base.source_node);
elem_ptr_instruction->base.base.source_node);
if (array_ptr_val == nullptr)
return ira->codegen->invalid_inst_gen;

9
test/compile_errors.zig
View File

@ -3,6 +3,15 @@ const builtin = @import("builtin");
const Target = @import("std").Target;
pub fn addCases(cases: *tests.CompileErrorContext) void {
cases.addTest("access of undefined pointer to array",
\\const ram_u32: *[4096]u32 = undefined;
\\export fn entry() void {
\\ @ptrCast(*u32, &(ram_u32[0])) = &(ram_u32[0]);
\\}
, &[_][]const u8{
"tmp.zig:3:29: error: use of undefined value here causes undefined behavior",
});
cases.addTest("duplicate field in anonymous struct literal",
\\export fn entry() void {
\\ const anon = .{