[dfsan] Expose dfsan_get_track_origins to get origin tracking status

This allows application code checks if origin tracking is on before
printing out traces.

-dfsan-track-origins can be 0,1,2.
The current code only distinguishes 1 and 2 in compile time, but not at runtime.
Made runtime distinguish 1 and 2 too.

Reviewed By: browneee

Differential Revision: https://reviews.llvm.org/D105128
This commit is contained in:
Jianzhou Zhao 2021-06-29 06:17:00 +00:00
parent 485cc55edf
commit ae6648cee0
6 changed files with 41 additions and 17 deletions

View File

@ -141,6 +141,12 @@ size_t dfsan_sprint_stack_trace(char *out_buf, size_t out_buf_size);
/// Retrieves the very first origin associated with the data at the given
/// address.
dfsan_origin dfsan_get_init_origin(const void *addr);
/// Returns the value of -dfsan-track-origins.
/// * 0: do not track origins.
/// * 1: track origins at memory store operations.
/// * 2: track origins at memory load and store operations.
int dfsan_get_track_origins(void);
#ifdef __cplusplus
} // extern "C"

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@ -55,10 +55,11 @@ SANITIZER_INTERFACE_ATTRIBUTE THREADLOCAL u32
// Instrumented code may set this value in terms of -dfsan-track-origins.
// * undefined or 0: do not track origins.
// * 1: track origins at memory store operations.
// * 2: TODO: track origins at memory store operations and callsites.
// * 2: track origins at memory load and store operations.
// TODO: track callsites.
extern "C" SANITIZER_WEAK_ATTRIBUTE const int __dfsan_track_origins;
int __dfsan_get_track_origins() {
extern "C" SANITIZER_INTERFACE_ATTRIBUTE int dfsan_get_track_origins() {
return &__dfsan_track_origins ? __dfsan_track_origins : 0;
}
@ -446,7 +447,7 @@ void dfsan_copy_memory(void *dst, const void *src, uptr size) {
internal_memcpy(dst, src, size);
internal_memcpy((void *)shadow_for(dst), (const void *)shadow_for(src),
size * sizeof(dfsan_label));
if (__dfsan_get_track_origins())
if (dfsan_get_track_origins())
dfsan_mem_origin_transfer(dst, src, size);
}
@ -514,12 +515,12 @@ void SetShadow(dfsan_label label, void *addr, uptr size, dfsan_origin origin) {
if (0 != label) {
const uptr beg_shadow_addr = (uptr)__dfsan::shadow_for(addr);
WriteShadowWithSize(label, beg_shadow_addr, size);
if (__dfsan_get_track_origins())
if (dfsan_get_track_origins())
SetOrigin(addr, size, origin);
return;
}
if (__dfsan_get_track_origins())
if (dfsan_get_track_origins())
ReleaseOrigins(addr, size);
ReleaseOrClearShadows(addr, size);
@ -533,7 +534,7 @@ extern "C" SANITIZER_INTERFACE_ATTRIBUTE void __dfsan_set_label(
SANITIZER_INTERFACE_ATTRIBUTE
void dfsan_set_label(dfsan_label label, void *addr, uptr size) {
dfsan_origin init_origin = 0;
if (label && __dfsan_get_track_origins()) {
if (label && dfsan_get_track_origins()) {
GET_CALLER_PC_BP;
GET_STORE_STACK_TRACE_PC_BP(pc, bp);
init_origin = ChainOrigin(0, &stack, true);
@ -546,7 +547,7 @@ void dfsan_add_label(dfsan_label label, void *addr, uptr size) {
if (0 == label)
return;
if (__dfsan_get_track_origins()) {
if (dfsan_get_track_origins()) {
GET_CALLER_PC_BP;
GET_STORE_STACK_TRACE_PC_BP(pc, bp);
dfsan_origin init_origin = ChainOrigin(0, &stack, true);
@ -648,7 +649,7 @@ void PrintInvalidOriginWarning(dfsan_label label, const void *address) {
bool PrintOriginTraceToStr(const void *addr, const char *description,
InternalScopedString *out) {
CHECK(out);
CHECK(__dfsan_get_track_origins());
CHECK(dfsan_get_track_origins());
Decorator d;
const dfsan_label label = *__dfsan::shadow_for(addr);
@ -687,7 +688,7 @@ bool PrintOriginTraceToStr(const void *addr, const char *description,
extern "C" SANITIZER_INTERFACE_ATTRIBUTE void dfsan_print_origin_trace(
const void *addr, const char *description) {
if (!__dfsan_get_track_origins()) {
if (!dfsan_get_track_origins()) {
PrintNoOriginTrackingWarning();
return;
}
@ -713,7 +714,7 @@ dfsan_sprint_origin_trace(const void *addr, const char *description,
char *out_buf, size_t out_buf_size) {
CHECK(out_buf);
if (!__dfsan_get_track_origins()) {
if (!dfsan_get_track_origins()) {
PrintNoOriginTrackingWarning();
return 0;
}
@ -742,7 +743,7 @@ dfsan_sprint_origin_trace(const void *addr, const char *description,
extern "C" SANITIZER_INTERFACE_ATTRIBUTE dfsan_origin
dfsan_get_init_origin(const void *addr) {
if (!__dfsan_get_track_origins())
if (!dfsan_get_track_origins())
return 0;
const dfsan_label label = *__dfsan::shadow_for(addr);
@ -829,7 +830,7 @@ void dfsan_clear_thread_local_state() {
internal_memset(__dfsan_arg_tls, 0, sizeof(__dfsan_arg_tls));
internal_memset(__dfsan_retval_tls, 0, sizeof(__dfsan_retval_tls));
if (__dfsan_get_track_origins()) {
if (dfsan_get_track_origins()) {
internal_memset(__dfsan_arg_origin_tls, 0, sizeof(__dfsan_arg_origin_tls));
internal_memset(&__dfsan_retval_origin_tls, 0,
sizeof(__dfsan_retval_origin_tls));
@ -995,7 +996,7 @@ static void DFsanInit(int argc, char **argv, char **envp) {
CheckASLR();
InitShadow(__dfsan_get_track_origins());
InitShadow(dfsan_get_track_origins());
initialize_interceptors();

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@ -38,7 +38,8 @@ fun:dfsan_get_origin=uninstrumented
fun:dfsan_get_origin=custom
fun:dfsan_get_init_origin=uninstrumented
fun:dfsan_get_init_origin=discard
fun:dfsan_get_track_origins=uninstrumented
fun:dfsan_get_track_origins=discard
###############################################################################
# glibc

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@ -0,0 +1,13 @@
// RUN: %clang_dfsan -DTRACK_ORIGINS=2 -mllvm -dfsan-track-origins=2 %s -o %t && %run %t
// RUN: %clang_dfsan -DTRACK_ORIGINS=1 -mllvm -dfsan-track-origins=1 %s -o %t && %run %t
// RUN: %clang_dfsan -DTRACK_ORIGINS=0 %s -o %t && %run %t
//
// REQUIRES: x86_64-target-arch
#include <sanitizer/dfsan_interface.h>
#include <assert.h>
int main(int argc, char *argv[]) {
assert(dfsan_get_track_origins() == TRACK_ORIGINS);
}

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@ -1397,7 +1397,8 @@ bool DataFlowSanitizer::runImpl(Module &M) {
Changed = true;
return new GlobalVariable(
M, OriginTy, true, GlobalValue::WeakODRLinkage,
ConstantInt::getSigned(OriginTy, shouldTrackOrigins()),
ConstantInt::getSigned(OriginTy,
shouldTrackOrigins() ? ClTrackOrigins : 0),
"__dfsan_track_origins");
});

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@ -1,5 +1,6 @@
; RUN: opt < %s -dfsan -S | FileCheck %s --check-prefixes=CHECK,CHECK_NO_ORIGIN -DSHADOW_XOR_MASK=87960930222080 --dump-input-context=100
; RUN: opt < %s -dfsan -dfsan-track-origins=1 -S | FileCheck %s --check-prefixes=CHECK,CHECK_ORIGIN -DSHADOW_XOR_MASK=87960930222080 --dump-input-context=100
; RUN: opt < %s -dfsan -dfsan-track-origins=1 -S | FileCheck %s --check-prefixes=CHECK,CHECK_ORIGIN1 -DSHADOW_XOR_MASK=87960930222080 --dump-input-context=100
; RUN: opt < %s -dfsan -dfsan-track-origins=2 -S | FileCheck %s --check-prefixes=CHECK_ORIGIN2 -DSHADOW_XOR_MASK=87960930222080 --dump-input-context=100
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@ -8,7 +9,8 @@ target triple = "x86_64-unknown-linux-gnu"
; CHECK: @__dfsan_arg_origin_tls = external thread_local(initialexec) global [200 x i32]
; CHECK: @__dfsan_retval_origin_tls = external thread_local(initialexec) global i32
; CHECK_NO_ORIGIN: @__dfsan_track_origins = weak_odr constant i32 0
; CHECK_ORIGIN: @__dfsan_track_origins = weak_odr constant i32 1
; CHECK_ORIGIN1: @__dfsan_track_origins = weak_odr constant i32 1
; CHECK_ORIGIN2: @__dfsan_track_origins = weak_odr constant i32 2
; CHECK: @__dfsan_shadow_width_bits = weak_odr constant i32 [[#SBITS:]]
; CHECK: @__dfsan_shadow_width_bytes = weak_odr constant i32 [[#SBYTES:]]