[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: 246435
This commit is contained in:
Kuba Brecka 2015-08-31 12:41:55 +00:00
parent f506f41434
commit b79932addf
2 changed files with 17 additions and 2 deletions

View File

@ -4769,7 +4769,7 @@ 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);
@ -4800,7 +4800,7 @@ 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 +1,15 @@
// RUN: %clangxx_asan -O0 %s -o %t && %run %t
// This fails on i386 Linux due to a glibc versioned symbols mixup.
// REQUIRES: asan-64-bits
#include <assert.h>
#include <stdio.h>
int main() {
FILE *fp = fopen("/dev/null", "w");
assert(fp);
freopen(NULL, "a", fp);
fclose(fp);
return 0;
}