[sanitizer] Fix mallopt interceptor.

On error, mallopt is supposed to return 0, not -1.

llvm-svn: 345323

compiler-rt/lib/asan/asan_malloc_linux.cc

@@ -209,7 +209,7 @@ INTERCEPTOR(struct fake_mallinfo, mallinfo, void) {
 }
 
 INTERCEPTOR(int, mallopt, int cmd, int value) {
-  return -1;
+  return 0;
 }
 #endif // SANITIZER_INTERCEPT_MALLOPT_AND_MALLINFO
 

compiler-rt/lib/hwasan/hwasan_interceptors.cc

@@ -186,7 +186,7 @@ struct __sanitizer_struct_mallinfo __sanitizer_mallinfo() {
 }
 
 int __sanitizer_mallopt(int cmd, int value) {
-  return -1;
+  return 0;
 }
 
 void __sanitizer_malloc_stats(void) {

compiler-rt/lib/lsan/lsan_interceptors.cc

@@ -153,7 +153,7 @@ INTERCEPTOR(struct fake_mallinfo, mallinfo, void) {
 #define LSAN_MAYBE_INTERCEPT_MALLINFO INTERCEPT_FUNCTION(mallinfo)
 
 INTERCEPTOR(int, mallopt, int cmd, int value) {
-  return -1;
+  return 0;
 }
 #define LSAN_MAYBE_INTERCEPT_MALLOPT INTERCEPT_FUNCTION(mallopt)
 #else

compiler-rt/lib/msan/msan_interceptors.cc

@@ -265,7 +265,7 @@ INTERCEPTOR(void, mallinfo, __sanitizer_struct_mallinfo *sret) {
 
 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 INTERCEPTOR(int, mallopt, int cmd, int value) {
-  return -1;
+  return 0;
 }
 #define MSAN_MAYBE_INTERCEPT_MALLOPT INTERCEPT_FUNCTION(mallopt)
 #else

compiler-rt/lib/scudo/scudo_malloc.cpp

@@ -79,7 +79,7 @@ INTERCEPTOR_ATTRIBUTE size_t malloc_usable_size(void *ptr) {
 
 #if SANITIZER_INTERCEPT_MALLOPT_AND_MALLINFO
 INTERCEPTOR_ATTRIBUTE int mallopt(int cmd, int value) {
-  return -1;
+  return 0;
 }
 #endif
 }  // extern "C"

compiler-rt/test/sanitizer_common/TestCases/Linux/mallopt.cc

@@ -0,0 +1,9 @@
+// Check that mallopt does not return invalid values (ex. -1).
+// RUN: %clangxx -O2 %s -o %t && %run %t
+#include <assert.h>
+#include <malloc.h>
+
+int main() {
+  int res = mallopt(M_ARENA_MAX, 0);
+  assert(res == 0 || res == 1);
+}