mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-15 04:20:28 +08:00
35dc62de3d
Add new file libio/tst-fclose-unopened2.c that tests whether fclose on an unopened file returns EOF. This test differs from tst-fclose-unopened.c by ensuring the file's buffer is allocated prior to double-fclose. A comment in tst-fclose-unopened.c now clarifies that it is testing a file with an unallocated buffer. Calling fclose on unopened files normally causes a use-after-free bug, however the standard streams are an exception since they are not deallocated by fclose. Tested for x86_64. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
52 lines
1.7 KiB
C
52 lines
1.7 KiB
C
/* Test using fclose on an unopened file.
|
|
Copyright (C) 2024 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <mcheck.h>
|
|
#include <stdio.h>
|
|
#include <support/check.h>
|
|
|
|
/* Verify that fclose on an unopened file returns EOF. This test uses
|
|
a file with an allocated buffer.
|
|
|
|
This is not part of the fclose external contract but there are
|
|
dependencies on this behaviour. */
|
|
|
|
static int
|
|
do_test (void)
|
|
{
|
|
mtrace ();
|
|
|
|
/* Input file tst-fclose-unopened2.input has 6 bytes plus newline. */
|
|
char buf[6];
|
|
|
|
/* Read from the file to ensure its internal buffer is allocated. */
|
|
TEST_COMPARE (fread (buf, 1, sizeof (buf), stdin), sizeof (buf));
|
|
|
|
TEST_COMPARE (fclose (stdin), 0);
|
|
|
|
/* Attempt to close the unopened file and verify that EOF is returned.
|
|
Calling fclose on a file twice normally causes a use-after-free bug,
|
|
however the standard streams are an exception since they are not
|
|
deallocated by fclose. */
|
|
TEST_COMPARE (fclose (stdin), EOF);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#include <support/test-driver.c>
|