[asan] Fix the freopen interceptor to allow NULL instead of a filename

According to man freopen, passing NULL instead of a filename is valid, however the current implementation of the interceptor assumes this parameter is non-NULL. Let's fix that and add a test case.

Differential Revision: http://reviews.llvm.org/D11389

llvm-svn: 242787
This commit is contained in:
Kuba Brecka 2015-07-21 14:23:27 +00:00
parent 33e746f21b
commit 4c0cdec138
2 changed files with 14 additions and 2 deletions

View File

@ -4671,7 +4671,7 @@ INTERCEPTOR(__sanitizer_FILE *, freopen, const char *path, const char *mode,
__sanitizer_FILE *fp) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, freopen, path, mode, fp);
COMMON_INTERCEPTOR_READ_RANGE(ctx, path, REAL(strlen)(path) + 1);
if (path) COMMON_INTERCEPTOR_READ_RANGE(ctx, path, REAL(strlen)(path) + 1);
COMMON_INTERCEPTOR_READ_RANGE(ctx, mode, REAL(strlen)(mode) + 1);
COMMON_INTERCEPTOR_FILE_CLOSE(ctx, fp);
__sanitizer_FILE *res = REAL(freopen)(path, mode, fp);
@ -4702,7 +4702,7 @@ INTERCEPTOR(__sanitizer_FILE *, freopen64, const char *path, const char *mode,
__sanitizer_FILE *fp) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, freopen64, path, mode, fp);
COMMON_INTERCEPTOR_READ_RANGE(ctx, path, REAL(strlen)(path) + 1);
if (path) COMMON_INTERCEPTOR_READ_RANGE(ctx, path, REAL(strlen)(path) + 1);
COMMON_INTERCEPTOR_READ_RANGE(ctx, mode, REAL(strlen)(mode) + 1);
COMMON_INTERCEPTOR_FILE_CLOSE(ctx, fp);
__sanitizer_FILE *res = REAL(freopen64)(path, mode, fp);

View File

@ -0,0 +1,12 @@
// RUN: %clangxx_asan -O0 %s -o %t && %run %t
#include <assert.h>
#include <stdio.h>
int main() {
FILE *fp = fopen("/dev/null", "w");
assert(fp);
freopen(NULL, "a", fp);
fclose(fp);
return 0;
}