Re: [PATCH v3 6/7] Use PRINTF_FORTIFY instead of _IO_FLAGS2_FORTIFY (bug 11319)

["Gabriel F. T. Gomes" <gabriel at inconstante dot eti dot br>]

On Tue, 04 Dec 2018, Adhemerval Zanella wrote:

>On 04/12/2018 16:01, Gabriel F. T. Gomes wrote:
>>
>> +#ifndef _GNU_SOURCE
>> +# define _GNU_SOURCE	1
>> +#endif  
>
>I think we can define it regardless

OK.

>> +#include <errno.h>
>> +#include <stdio.h>
>> +#include <string.h>
>> +#include <sys/eventfd.h>  
>
>eventfd is Linux specific, so either we need to move this test to Linux
>sysdeps or use a platform neutral way to stress this issue.

Oh, indeed.

>> +
>> +#include <support/check.h>
>> +
>> +static int
>> +do_test (void)
>> +{
>> +  int ret;
>> +  int fd = eventfd(0, 0);  
>
>To stress this issue we just need a valid file descriptor that is seekable
>but fail on a write.  Just use a temporary file opened in read-only mode.

Does the following patch look better (thanks for the suggestion)?

From d992bc941921988fee31ff8b3fc13fb406f89b93 Mon Sep 17 00:00:00 2001
From: "Gabriel F. T. Gomes" <gabriel@inconstante.eti.br>
Date: Tue, 4 Dec 2018 15:57:57 -0200
Subject: [PATCH v2] Add test for bug 11319

The commit

commit 7ca890b88e6ab7624afb1742a9fffb37ad5b3fc3
Author: Ulrich Drepper <drepper@redhat.com>
Date:   Wed Feb 24 16:07:57 2010 -0800

    Fix reporting of I/O errors in *dprintf functions.

fixed bug 11319 for dprintf and vdprintf, however, it did not fix it for
__dprintf_chk and __vdprintf_chk.  As a side-effect of the refactoring
of libio functions, this bug is also fixed for the foritified functions.
This patch adds a test case to avoid regressions.

Tested for powerpc64le and x86_64.

	* stdio-common/Makefile (tests): Add tst-bz11319 and
	tst-bz11319-fortify2.
	(CFLAGS-tst-bz11319-fortify2.c): New macro.
	* stdio-common/tst-bz11319-fortify2.c: New file.
	* stdio-common/tst-bz11319.c: Likewise.
---
 stdio-common/Makefile               |  6 ++++-
 stdio-common/tst-bz11319-fortify2.c |  1 +
 stdio-common/tst-bz11319.c          | 52 +++++++++++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+), 1 deletion(-)
 create mode 100644 stdio-common/tst-bz11319-fortify2.c
 create mode 100644 stdio-common/tst-bz11319.c

diff --git a/stdio-common/Makefile b/stdio-common/Makefile
index 84bad1fafe..8978b3fb1f 100644
--- a/stdio-common/Makefile
+++ b/stdio-common/Makefile
@@ -64,7 +64,7 @@ tests := tstscanf test_rdwr test-popen tstgetln test-fseek \
 	 tst-vfprintf-user-type \
 	 tst-vfprintf-mbs-prec \
 	 tst-scanf-round \
-	 tst-renameat2 \
+	 tst-renameat2 tst-bz11319 tst-bz11319-fortify2 \
 
 test-srcs = tst-unbputc tst-printf tst-printfsz-islongdouble
 
@@ -164,6 +164,10 @@ CFLAGS-test_rdwr.c += -DOBJPFX=\"$(objpfx)\"
 # tst-gets.c tests a deprecated function.
 CFLAGS-tst-gets.c += -Wno-deprecated-declarations
 
+# BZ #11319 was first fixed for regular vdprintf, then reopened because
+# the fortified version had the same bug.
+CFLAGS-tst-bz11319-fortify2.c += -D_FORTIFY_SOURCE=2
+
 CPPFLAGS += $(libio-mtsafe)
 
 $(objpfx)tst-setvbuf1.out: /dev/null $(objpfx)tst-setvbuf1
diff --git a/stdio-common/tst-bz11319-fortify2.c b/stdio-common/tst-bz11319-fortify2.c
new file mode 100644
index 0000000000..a8df9a39bd
--- /dev/null
+++ b/stdio-common/tst-bz11319-fortify2.c
@@ -0,0 +1 @@
+#include <tst-bz11319.c>
diff --git a/stdio-common/tst-bz11319.c b/stdio-common/tst-bz11319.c
new file mode 100644
index 0000000000..29fbd729ab
--- /dev/null
+++ b/stdio-common/tst-bz11319.c
@@ -0,0 +1,52 @@
+/* Regression test for bug 11319.
+   Copyright (C) 2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#define _GNU_SOURCE 1
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <support/check.h>
+#include <support/temp_file.h>
+#include <support/xstdio.h>
+
+static int
+do_test (void)
+{
+  char *tempfile;
+  int ret;
+  FILE *fp;
+
+  /* Create a temporary file and open it in read-only mode.  */
+  TEST_VERIFY_EXIT (create_temp_file ("tst-bz11319", &tempfile));
+  fp = xfopen (tempfile, "r");
+
+  /* Try and write to the temporary file to intentionally fail, then
+     check that dprintf (or __dprintf_chk) return EOF.  */
+  ret = dprintf (fp->_fileno, "%d", 0);
+  TEST_VERIFY (ret == EOF);
+
+  /* Clean up.  */
+  xfclose (fp);
+  if (tempfile)
+    free (tempfile);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
-- 
2.14.5