Commit 8918cb06fc
Changed files (6)
lib/std/debug.zig
@@ -219,7 +219,7 @@ pub fn panic(comptime format: []const u8, args: var) noreturn {
}
/// TODO multithreaded awareness
-var panicking: u8 = 0; // TODO make this a bool
+var panicking: u8 = 0;
pub fn panicExtra(trace: ?*const builtin.StackTrace, first_trace_addr: ?usize, comptime format: []const u8, args: var) noreturn {
@setCold(true);
@@ -230,21 +230,25 @@ pub fn panicExtra(trace: ?*const builtin.StackTrace, first_trace_addr: ?usize, c
resetSegfaultHandler();
}
- if (@atomicRmw(u8, &panicking, builtin.AtomicRmwOp.Xchg, 1, builtin.AtomicOrder.SeqCst) == 1) {
- // Panicked during a panic.
-
- // TODO detect if a different thread caused the panic, because in that case
- // we would want to return here instead of calling abort, so that the thread
- // which first called panic can finish printing a stack trace.
- os.abort();
- }
- const stderr = getStderrStream();
- stderr.print(format ++ "\n", args) catch os.abort();
- if (trace) |t| {
- dumpStackTrace(t.*);
+ switch (@atomicRmw(u8, &panicking, .Add, 1, .SeqCst)) {
+ 0 => {
+ const stderr = getStderrStream();
+ stderr.print(format ++ "\n", args) catch os.abort();
+ if (trace) |t| {
+ dumpStackTrace(t.*);
+ }
+ dumpCurrentStackTrace(first_trace_addr);
+ },
+ 1 => {
+ // TODO detect if a different thread caused the panic, because in that case
+ // we would want to return here instead of calling abort, so that the thread
+ // which first called panic can finish printing a stack trace.
+ warn("Panicked during a panic. Aborting.\n", .{});
+ },
+ else => {
+ // Panicked while printing "Panicked during a panic."
+ },
}
- dumpCurrentStackTrace(first_trace_addr);
-
os.abort();
}
lib/std/mem.zig
@@ -364,11 +364,11 @@ pub fn len(comptime T: type, ptr: [*:0]const T) usize {
}
pub fn toSliceConst(comptime T: type, ptr: [*:0]const T) [:0]const T {
- return ptr[0..len(T, ptr)];
+ return ptr[0..len(T, ptr) :0];
}
pub fn toSlice(comptime T: type, ptr: [*:0]T) [:0]T {
- return ptr[0..len(T, ptr)];
+ return ptr[0..len(T, ptr) :0];
}
/// Returns true if all elements in a slice are equal to the scalar value provided
src/all_types.hpp
@@ -1779,6 +1779,7 @@ enum PanicMsgId {
PanicMsgIdResumedFnPendingAwait,
PanicMsgIdBadNoAsyncCall,
PanicMsgIdResumeNotSuspendedFn,
+ PanicMsgIdBadSentinel,
PanicMsgIdCount,
};
src/codegen.cpp
@@ -941,6 +941,8 @@ static Buf *panic_msg_buf(PanicMsgId msg_id) {
return buf_create_from_str("async function called with noasync suspended");
case PanicMsgIdResumeNotSuspendedFn:
return buf_create_from_str("resumed a non-suspended function");
+ case PanicMsgIdBadSentinel:
+ return buf_create_from_str("sentinel mismatch");
}
zig_unreachable();
}
@@ -1419,6 +1421,22 @@ static void add_bounds_check(CodeGen *g, LLVMValueRef target_val,
LLVMPositionBuilderAtEnd(g->builder, ok_block);
}
+static void add_sentinel_check(CodeGen *g, LLVMValueRef sentinel_elem_ptr, ZigValue *sentinel) {
+ LLVMValueRef expected_sentinel = gen_const_val(g, sentinel, "");
+
+ LLVMValueRef actual_sentinel = gen_load_untyped(g, sentinel_elem_ptr, 0, false, "");
+ LLVMValueRef ok_bit = LLVMBuildICmp(g->builder, LLVMIntEQ, actual_sentinel, expected_sentinel, "");
+
+ LLVMBasicBlockRef fail_block = LLVMAppendBasicBlock(g->cur_fn_val, "SentinelFail");
+ LLVMBasicBlockRef ok_block = LLVMAppendBasicBlock(g->cur_fn_val, "SentinelOk");
+ LLVMBuildCondBr(g->builder, ok_bit, ok_block, fail_block);
+
+ LLVMPositionBuilderAtEnd(g->builder, fail_block);
+ gen_safety_crash(g, PanicMsgIdBadSentinel);
+
+ LLVMPositionBuilderAtEnd(g->builder, ok_block);
+}
+
static LLVMValueRef gen_assert_zero(CodeGen *g, LLVMValueRef expr_val, ZigType *int_type) {
LLVMValueRef zero = LLVMConstNull(get_llvm_type(g, int_type));
LLVMValueRef ok_bit = LLVMBuildICmp(g->builder, LLVMIntEQ, expr_val, zero, "");
@@ -5244,6 +5262,9 @@ static LLVMValueRef ir_render_slice(CodeGen *g, IrExecutable *executable, IrInst
bool want_runtime_safety = instruction->safety_check_on && ir_want_runtime_safety(g, &instruction->base);
+ ZigType *res_slice_ptr_type = instruction->base.value->type->data.structure.fields[slice_ptr_index]->type_entry;
+ ZigValue *sentinel = res_slice_ptr_type->data.pointer.sentinel;
+
if (array_type->id == ZigTypeIdArray ||
(array_type->id == ZigTypeIdPointer && array_type->data.pointer.ptr_len == PtrLenSingle))
{
@@ -5265,6 +5286,15 @@ static LLVMValueRef ir_render_slice(CodeGen *g, IrExecutable *executable, IrInst
LLVMValueRef array_end = LLVMConstInt(g->builtin_types.entry_usize->llvm_type,
array_type->data.array.len, false);
add_bounds_check(g, end_val, LLVMIntEQ, nullptr, LLVMIntULE, array_end);
+
+ if (sentinel != nullptr) {
+ LLVMValueRef indices[] = {
+ LLVMConstNull(g->builtin_types.entry_usize->llvm_type),
+ end_val,
+ };
+ LLVMValueRef sentinel_elem_ptr = LLVMBuildInBoundsGEP(g->builder, array_ptr, indices, 2, "");
+ add_sentinel_check(g, sentinel_elem_ptr, sentinel);
+ }
}
}
if (!type_has_bits(array_type)) {
@@ -5297,6 +5327,10 @@ static LLVMValueRef ir_render_slice(CodeGen *g, IrExecutable *executable, IrInst
if (want_runtime_safety) {
add_bounds_check(g, start_val, LLVMIntEQ, nullptr, LLVMIntULE, end_val);
+ if (sentinel != nullptr) {
+ LLVMValueRef sentinel_elem_ptr = LLVMBuildInBoundsGEP(g->builder, array_ptr, &end_val, 1, "");
+ add_sentinel_check(g, sentinel_elem_ptr, sentinel);
+ }
}
if (type_has_bits(array_type)) {
@@ -5337,18 +5371,24 @@ static LLVMValueRef ir_render_slice(CodeGen *g, IrExecutable *executable, IrInst
end_val = prev_end;
}
+ LLVMValueRef src_ptr_ptr = LLVMBuildStructGEP(g->builder, array_ptr, (unsigned)ptr_index, "");
+ LLVMValueRef src_ptr = gen_load_untyped(g, src_ptr_ptr, 0, false, "");
+
if (want_runtime_safety) {
assert(prev_end);
add_bounds_check(g, start_val, LLVMIntEQ, nullptr, LLVMIntULE, end_val);
if (instruction->end) {
add_bounds_check(g, end_val, LLVMIntEQ, nullptr, LLVMIntULE, prev_end);
+
+ if (sentinel != nullptr) {
+ LLVMValueRef sentinel_elem_ptr = LLVMBuildInBoundsGEP(g->builder, src_ptr, &end_val, 1, "");
+ add_sentinel_check(g, sentinel_elem_ptr, sentinel);
+ }
}
}
- LLVMValueRef src_ptr_ptr = LLVMBuildStructGEP(g->builder, array_ptr, (unsigned)ptr_index, "");
- LLVMValueRef src_ptr = gen_load_untyped(g, src_ptr_ptr, 0, false, "");
LLVMValueRef ptr_field_ptr = LLVMBuildStructGEP(g->builder, tmp_struct_ptr, (unsigned)ptr_index, "");
- LLVMValueRef slice_start_ptr = LLVMBuildInBoundsGEP(g->builder, src_ptr, &start_val, (unsigned)len_index, "");
+ LLVMValueRef slice_start_ptr = LLVMBuildInBoundsGEP(g->builder, src_ptr, &start_val, 1, "");
gen_store_untyped(g, slice_start_ptr, ptr_field_ptr, 0, false);
LLVMValueRef len_field_ptr = LLVMBuildStructGEP(g->builder, tmp_struct_ptr, (unsigned)len_index, "");
src/ir.cpp
@@ -25122,14 +25122,16 @@ static IrInstruction *ir_analyze_instruction_slice(IrAnalyze *ira, IrInstruction
if (array_type->data.pointer.ptr_len == PtrLenC) {
array_type = adjust_ptr_len(ira->codegen, array_type, PtrLenUnknown);
}
- non_sentinel_slice_ptr_type = array_type;
+ ZigType *maybe_sentineled_slice_ptr_type = array_type;
+ non_sentinel_slice_ptr_type = adjust_ptr_sentinel(ira->codegen, maybe_sentineled_slice_ptr_type, nullptr);
if (!end) {
ir_add_error(ira, &instruction->base, buf_sprintf("slice of pointer must include end value"));
return ira->codegen->invalid_instruction;
}
}
} else if (is_slice(array_type)) {
- non_sentinel_slice_ptr_type = array_type->data.structure.fields[slice_ptr_index]->type_entry;
+ ZigType *maybe_sentineled_slice_ptr_type = array_type->data.structure.fields[slice_ptr_index]->type_entry;
+ non_sentinel_slice_ptr_type = adjust_ptr_sentinel(ira->codegen, maybe_sentineled_slice_ptr_type, nullptr);
elem_type = non_sentinel_slice_ptr_type->data.pointer.child_type;
} else {
ir_add_error(ira, &instruction->base,
test/runtime_safety.zig
@@ -1,12 +1,57 @@
const tests = @import("tests.zig");
pub fn addCases(cases: *tests.CompareOutputContext) void {
+ cases.addRuntimeSafety("pointer slice sentinel mismatch",
+ \\const std = @import("std");
+ \\pub fn panic(message: []const u8, stack_trace: ?*@import("builtin").StackTrace) noreturn {
+ \\ if (std.mem.eql(u8, message, "sentinel mismatch")) {
+ \\ std.process.exit(126); // good
+ \\ }
+ \\ std.process.exit(0); // test failed
+ \\}
+ \\pub fn main() void {
+ \\ var buf: [4]u8 = undefined;
+ \\ const ptr = buf[0..].ptr;
+ \\ const slice = ptr[0..3 :0];
+ \\}
+ );
+
+ cases.addRuntimeSafety("slice slice sentinel mismatch",
+ \\const std = @import("std");
+ \\pub fn panic(message: []const u8, stack_trace: ?*@import("builtin").StackTrace) noreturn {
+ \\ if (std.mem.eql(u8, message, "sentinel mismatch")) {
+ \\ std.process.exit(126); // good
+ \\ }
+ \\ std.process.exit(0); // test failed
+ \\}
+ \\pub fn main() void {
+ \\ var buf: [4]u8 = undefined;
+ \\ const slice = buf[0..];
+ \\ const slice2 = slice[0..3 :0];
+ \\}
+ );
+
+ cases.addRuntimeSafety("array slice sentinel mismatch",
+ \\const std = @import("std");
+ \\pub fn panic(message: []const u8, stack_trace: ?*@import("builtin").StackTrace) noreturn {
+ \\ if (std.mem.eql(u8, message, "sentinel mismatch")) {
+ \\ std.process.exit(126); // good
+ \\ }
+ \\ std.process.exit(0); // test failed
+ \\}
+ \\pub fn main() void {
+ \\ var buf: [4]u8 = undefined;
+ \\ const slice = buf[0..3 :0];
+ \\}
+ );
+
cases.addRuntimeSafety("intToPtr with misaligned address",
+ \\const std = @import("std");
\\pub fn panic(message: []const u8, stack_trace: ?*@import("builtin").StackTrace) noreturn {
- \\ if (@import("std").mem.eql(u8, message, "incorrect alignment")) {
- \\ @import("std").os.exit(126); // good
+ \\ if (std.mem.eql(u8, message, "incorrect alignment")) {
+ \\ std.os.exit(126); // good
\\ }
- \\ @import("std").os.exit(0); // test failed
+ \\ std.os.exit(0); // test failed
\\}
\\pub fn main() void {
\\ var x: usize = 5;