| // RUN: %clang -target x86_64-linux-gnu -S -emit-llvm -o - %s | FileCheck -check-prefixes CHECK,WITHOUT %s |
| // RUN: %clang -target x86_64-linux-gnu -S -emit-llvm -o - %s -fsanitize=memory | FileCheck -check-prefixes CHECK,MSAN %s |
| // RUN: %clang -target x86_64-linux-gnu -S -emit-llvm -o - %s -fsanitize=kernel-memory | FileCheck -check-prefixes CHECK,KMSAN %s |
| |
| // Instrumented function. |
| // MSan uses memset(addr, -1, size) to poison allocas and stores shadow of the return value in |
| // __msan_retval_tls. KMSAN uses __msan_poison_alloca() to poison allocas and calls |
| // __msan_get_context_state() at function prologue to access the task context struct (including the |
| // shadow of the return value). |
| // |
| // CHECK-LABEL: i32 @instrumented1 |
| // KMSAN: __msan_get_context_state |
| // WITHOUT-NOT: __msan_poison_alloca |
| // WITHOUT-NOT: @llvm.memset |
| // MSAN: @llvm.memset{{.*}}({{.*}}, i8 -1 |
| // KMSAN: __msan_poison_alloca |
| // WITHOUT-NOT: __msan_retval_tls |
| // MSAN: __msan_retval_tls |
| // CHECK: ret i32 |
| int instrumented1(int *a) { |
| volatile char buf[8]; |
| return *a; |
| } |
| |
| // Function with no_sanitize("memory")/no_sanitize("kernel-memory"): no shadow propagation, but |
| // unpoisons memory to prevent false positives. |
| // MSan uses memset(addr, 0, size) to unpoison locals, KMSAN uses __msan_unpoison_alloca(). Both |
| // tools still access the retval shadow to write 0 to it. |
| // |
| // CHECK-LABEL: i32 @no_false_positives1 |
| // KMSAN: __msan_get_context_state |
| // WITHOUT-NOT: __msan_unpoison_alloca |
| // WITHOUT-NOT: @llvm.memset |
| // MSAN: @llvm.memset{{.*}}({{.*}}, i8 0 |
| // KMSAN: __msan_unpoison_alloca |
| // WITHOUT-NOT: __msan_retval_tls |
| // MSAN: __msan_retval_tls |
| // CHECK: ret i32 |
| __attribute__((no_sanitize("memory"))) __attribute__((no_sanitize("kernel-memory"))) int no_false_positives1(int *a) { |
| volatile char buf[8]; |
| return *a; |
| } |
| |
| // Function with disable_sanitizer_instrumentation: no instrumentation at all. |
| // |
| // CHECK-LABEL: i32 @no_instrumentation1 |
| // KMSAN-NOT: __msan_get_context_state |
| // WITHOUT-NOT: __msan_poison_alloca |
| // WITHOUT-NOT: @llvm.memset |
| // MSAN-NOT: @llvm.memset{{.*}}({{.*}}, i8 0 |
| // KMSAN-NOT: __msan_unpoison_alloca |
| // WITHOUT-NOT: __msan_retval_tls |
| // MSAN-NOT: __msan_retval_tls |
| // CHECK: ret i32 |
| __attribute__((disable_sanitizer_instrumentation)) int no_instrumentation1(int *a) { |
| volatile char buf[8]; |
| return *a; |
| } |
