Files
clang-p2996/clang/test/CodeGen/ubsan-function.cpp
Simon Tatham 20d6dee40d -fsanitize=function: fix alignment fault on Arm targets.
Function pointers are checked by loading a prefix structure from just
before the function's entry point. However, on Arm, the function
pointer is not always exactly equal to the address of the entry point,
because Thumb function pointers have the low bit set to tell the BX
instruction to enter them in Thumb state. So the generated code loads
from an odd address and suffers an alignment fault.

Fixed by clearing the low bit of the function pointer before
subtracting 8.

Differential Revision: https://reviews.llvm.org/D151308
2023-05-25 09:22:45 +01:00

36 lines
2.0 KiB
C++

// RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -o - %s -fsanitize=function -fno-sanitize-recover=all | FileCheck %s --check-prefixes=CHECK,64
// RUN: %clang_cc1 -triple aarch64-linux-gnu -emit-llvm -o - %s -fsanitize=function -fno-sanitize-recover=all | FileCheck %s --check-prefixes=CHECK,64
// RUN: %clang_cc1 -triple aarch64_be-linux-gnu -emit-llvm -o - %s -fsanitize=function -fno-sanitize-recover=all | FileCheck %s --check-prefixes=CHECK,64
// RUN: %clang_cc1 -triple arm-none-eabi -emit-llvm -o - %s -fsanitize=function -fno-sanitize-recover=all | FileCheck %s --check-prefixes=CHECK,ARM,32
// CHECK: define{{.*}} void @_Z3funv() #0 !func_sanitize ![[FUNCSAN:.*]] {
void fun() {}
// CHECK-LABEL: define{{.*}} void @_Z6callerPFvvE(ptr noundef %f)
// ARM: ptrtoint ptr {{.*}} to i32, !nosanitize !5
// ARM: and i32 {{.*}}, -2, !nosanitize !5
// ARM: inttoptr i32 {{.*}} to ptr, !nosanitize !5
// CHECK: getelementptr <{ i32, i32 }>, ptr {{.*}}, i32 -1, i32 0, !nosanitize
// CHECK: load i32, ptr {{.*}}, align {{.*}}, !nosanitize
// CHECK: icmp eq i32 {{.*}}, -1056584962, !nosanitize
// CHECK: br i1 {{.*}}, label %[[LABEL1:.*]], label %[[LABEL4:.*]], !nosanitize
// CHECK: [[LABEL1]]:
// CHECK: getelementptr <{ i32, i32 }>, ptr {{.*}}, i32 -1, i32 1, !nosanitize
// CHECK: load i32, ptr {{.*}}, align {{.*}}, !nosanitize
// CHECK: icmp eq i32 {{.*}}, -1522505972, !nosanitize
// CHECK: br i1 {{.*}}, label %[[LABEL3:.*]], label %[[LABEL2:[^,]*]], {{.*}}!nosanitize
// CHECK: [[LABEL2]]:
// 64: call void @__ubsan_handle_function_type_mismatch_abort(ptr @[[#]], i64 %[[#]]) #[[#]], !nosanitize
// 32: call void @__ubsan_handle_function_type_mismatch_abort(ptr @[[#]], i32 %[[#]]) #[[#]], !nosanitize
// CHECK-NEXT: unreachable, !nosanitize
// CHECK-EMPTY:
// CHECK-NEXT: [[LABEL3]]:
// CHECK: br label %[[LABEL4]], !nosanitize
// CHECK-EMPTY:
// CHECK-NEXT: [[LABEL4]]:
// CHECK-NEXT: call void
// CHECK-NEXT: ret void
void caller(void (*f)()) { f(); }
// CHECK: ![[FUNCSAN]] = !{i32 -1056584962, i32 -1522505972}