glibc/SOURCES/glibc-rh1682954.patch

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2020-01-21 19:14:46 +00:00
From 0d3905b110000463775b3fb189213833acaebf81 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Mon, 1 Jul 2019 12:23:10 -0700
Subject: Call _dl_open_check after relocation [BZ #24259]
This is a workaround for [BZ #20839] which doesn't remove the NODELETE
object when _dl_open_check throws an exception. Move it after relocation
in dl_open_worker to avoid leaving the NODELETE object mapped without
relocation.
[BZ #24259]
* elf/dl-open.c (dl_open_worker): Call _dl_open_check after
relocation.
* sysdeps/x86/Makefile (tests): Add tst-cet-legacy-5a,
tst-cet-legacy-5b, tst-cet-legacy-6a and tst-cet-legacy-6b.
(modules-names): Add tst-cet-legacy-mod-5a, tst-cet-legacy-mod-5b,
tst-cet-legacy-mod-5c, tst-cet-legacy-mod-6a, tst-cet-legacy-mod-6b
and tst-cet-legacy-mod-6c.
(CFLAGS-tst-cet-legacy-5a.c): New.
(CFLAGS-tst-cet-legacy-5b.c): Likewise.
(CFLAGS-tst-cet-legacy-mod-5a.c): Likewise.
(CFLAGS-tst-cet-legacy-mod-5b.c): Likewise.
(CFLAGS-tst-cet-legacy-mod-5c.c): Likewise.
(CFLAGS-tst-cet-legacy-6a.c): Likewise.
(CFLAGS-tst-cet-legacy-6b.c): Likewise.
(CFLAGS-tst-cet-legacy-mod-6a.c): Likewise.
(CFLAGS-tst-cet-legacy-mod-6b.c): Likewise.
(CFLAGS-tst-cet-legacy-mod-6c.c): Likewise.
($(objpfx)tst-cet-legacy-5a): Likewise.
($(objpfx)tst-cet-legacy-5a.out): Likewise.
($(objpfx)tst-cet-legacy-mod-5a.so): Likewise.
($(objpfx)tst-cet-legacy-mod-5b.so): Likewise.
($(objpfx)tst-cet-legacy-5b): Likewise.
($(objpfx)tst-cet-legacy-5b.out): Likewise.
(tst-cet-legacy-5b-ENV): Likewise.
($(objpfx)tst-cet-legacy-6a): Likewise.
($(objpfx)tst-cet-legacy-6a.out): Likewise.
($(objpfx)tst-cet-legacy-mod-6a.so): Likewise.
($(objpfx)tst-cet-legacy-mod-6b.so): Likewise.
($(objpfx)tst-cet-legacy-6b): Likewise.
($(objpfx)tst-cet-legacy-6b.out): Likewise.
(tst-cet-legacy-6b-ENV): Likewise.
* sysdeps/x86/tst-cet-legacy-5.c: New file.
* sysdeps/x86/tst-cet-legacy-5a.c: Likewise.
* sysdeps/x86/tst-cet-legacy-5b.c: Likewise.
* sysdeps/x86/tst-cet-legacy-6.c: Likewise.
* sysdeps/x86/tst-cet-legacy-6a.c: Likewise.
* sysdeps/x86/tst-cet-legacy-6b.c: Likewise.
* sysdeps/x86/tst-cet-legacy-mod-5.c: Likewise.
* sysdeps/x86/tst-cet-legacy-mod-5a.c: Likewise.
* sysdeps/x86/tst-cet-legacy-mod-5b.c: Likewise.
* sysdeps/x86/tst-cet-legacy-mod-5c.c: Likewise.
* sysdeps/x86/tst-cet-legacy-mod-6.c: Likewise.
* sysdeps/x86/tst-cet-legacy-mod-6a.c: Likewise.
* sysdeps/x86/tst-cet-legacy-mod-6b.c: Likewise.
* sysdeps/x86/tst-cet-legacy-mod-6c.c: Likewise.
(cherry picked from commit d0093c5cefb7f7a4143f3bb03743633823229cc6)
diff --git a/elf/dl-open.c b/elf/dl-open.c
index f6c8ef1043..518a6cad69 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -292,8 +292,6 @@ dl_open_worker (void *a)
_dl_debug_state ();
LIBC_PROBE (map_complete, 3, args->nsid, r, new);
- _dl_open_check (new);
-
/* Print scope information. */
if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_SCOPES))
_dl_show_scope (new, 0);
@@ -366,6 +364,12 @@ dl_open_worker (void *a)
_dl_relocate_object (l, l->l_scope, reloc_mode, 0);
}
+ /* NB: Workaround for [BZ #20839] which doesn't remove the NODELETE
+ object when _dl_open_check throws an exception. Move it after
+ relocation to avoid leaving the NODELETE object mapped without
+ relocation. */
+ _dl_open_check (new);
+
/* If the file is not loaded now as a dependency, add the search
list of the newly loaded object to the scope. */
bool any_tls = false;
diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile
index 337b0b63dc..43ad4a79ff 100644
--- a/sysdeps/x86/Makefile
+++ b/sysdeps/x86/Makefile
@@ -19,12 +19,17 @@ ifeq ($(subdir),elf)
sysdep-dl-routines += dl-cet
tests += tst-cet-legacy-1 tst-cet-legacy-2 tst-cet-legacy-2a \
- tst-cet-legacy-3 tst-cet-legacy-4
+ tst-cet-legacy-3 tst-cet-legacy-4 \
+ tst-cet-legacy-5a tst-cet-legacy-6a
ifneq (no,$(have-tunables))
-tests += tst-cet-legacy-4a tst-cet-legacy-4b tst-cet-legacy-4c
+tests += tst-cet-legacy-4a tst-cet-legacy-4b tst-cet-legacy-4c \
+ tst-cet-legacy-5b tst-cet-legacy-6b
endif
modules-names += tst-cet-legacy-mod-1 tst-cet-legacy-mod-2 \
- tst-cet-legacy-mod-4
+ tst-cet-legacy-mod-4 tst-cet-legacy-mod-5a \
+ tst-cet-legacy-mod-5b tst-cet-legacy-mod-5c \
+ tst-cet-legacy-mod-6a tst-cet-legacy-mod-6b \
+ tst-cet-legacy-mod-6c
CFLAGS-tst-cet-legacy-2.c += -fcf-protection=branch
CFLAGS-tst-cet-legacy-2a.c += -fcf-protection
@@ -35,6 +40,16 @@ CFLAGS-tst-cet-legacy-4.c += -fcf-protection=branch
CFLAGS-tst-cet-legacy-4a.c += -fcf-protection
CFLAGS-tst-cet-legacy-4b.c += -fcf-protection
CFLAGS-tst-cet-legacy-mod-4.c += -fcf-protection=none
+CFLAGS-tst-cet-legacy-5a.c += -fcf-protection
+CFLAGS-tst-cet-legacy-5b.c += -fcf-protection
+CFLAGS-tst-cet-legacy-mod-5a.c += -fcf-protection=none
+CFLAGS-tst-cet-legacy-mod-5b.c += -fcf-protection
+CFLAGS-tst-cet-legacy-mod-5c.c += -fcf-protection
+CFLAGS-tst-cet-legacy-6a.c += -fcf-protection
+CFLAGS-tst-cet-legacy-6b.c += -fcf-protection
+CFLAGS-tst-cet-legacy-mod-6a.c += -fcf-protection=none
+CFLAGS-tst-cet-legacy-mod-6b.c += -fcf-protection
+CFLAGS-tst-cet-legacy-mod-6c.c += -fcf-protection
$(objpfx)tst-cet-legacy-1: $(objpfx)tst-cet-legacy-mod-1.so \
$(objpfx)tst-cet-legacy-mod-2.so
@@ -44,6 +59,17 @@ $(objpfx)tst-cet-legacy-2a: $(objpfx)tst-cet-legacy-mod-2.so $(libdl)
$(objpfx)tst-cet-legacy-2a.out: $(objpfx)tst-cet-legacy-mod-1.so
$(objpfx)tst-cet-legacy-4: $(libdl)
$(objpfx)tst-cet-legacy-4.out: $(objpfx)tst-cet-legacy-mod-4.so
+$(objpfx)tst-cet-legacy-5a: $(libdl)
+$(objpfx)tst-cet-legacy-5a.out: $(objpfx)tst-cet-legacy-mod-5a.so \
+ $(objpfx)tst-cet-legacy-mod-5b.so
+$(objpfx)tst-cet-legacy-mod-5a.so: $(objpfx)tst-cet-legacy-mod-5c.so
+$(objpfx)tst-cet-legacy-mod-5b.so: $(objpfx)tst-cet-legacy-mod-5c.so
+$(objpfx)tst-cet-legacy-6a: $(libdl)
+$(objpfx)tst-cet-legacy-6a.out: $(objpfx)tst-cet-legacy-mod-6a.so \
+ $(objpfx)tst-cet-legacy-mod-6b.so
+$(objpfx)tst-cet-legacy-mod-6a.so: $(objpfx)tst-cet-legacy-mod-6c.so
+$(objpfx)tst-cet-legacy-mod-6b.so: $(objpfx)tst-cet-legacy-mod-6c.so
+LDFLAGS-tst-cet-legacy-mod-6c.so = -Wl,--enable-new-dtags,-z,nodelete
ifneq (no,$(have-tunables))
$(objpfx)tst-cet-legacy-4a: $(libdl)
$(objpfx)tst-cet-legacy-4a.out: $(objpfx)tst-cet-legacy-mod-4.so
@@ -54,6 +80,14 @@ tst-cet-legacy-4b-ENV = GLIBC_TUNABLES=glibc.tune.x86_shstk=on
$(objpfx)tst-cet-legacy-4c: $(libdl)
$(objpfx)tst-cet-legacy-4c.out: $(objpfx)tst-cet-legacy-mod-4.so
tst-cet-legacy-4c-ENV = GLIBC_TUNABLES=glibc.tune.x86_shstk=off
+$(objpfx)tst-cet-legacy-5b: $(libdl)
+$(objpfx)tst-cet-legacy-5b.out: $(objpfx)tst-cet-legacy-mod-5a.so \
+ $(objpfx)tst-cet-legacy-mod-5b.so
+tst-cet-legacy-5b-ENV = GLIBC_TUNABLES=glibc.tune.x86_ibt=off:glibc.tune.x86_shstk=off
+$(objpfx)tst-cet-legacy-6b: $(libdl)
+$(objpfx)tst-cet-legacy-6b.out: $(objpfx)tst-cet-legacy-mod-6a.so \
+ $(objpfx)tst-cet-legacy-mod-6b.so
+tst-cet-legacy-6b-ENV = GLIBC_TUNABLES=glibc.tune.x86_ibt=off:glibc.tune.x86_shstk=off
endif
endif
diff --git a/sysdeps/x86/tst-cet-legacy-5.c b/sysdeps/x86/tst-cet-legacy-5.c
new file mode 100644
index 0000000000..fbf640f664
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-5.c
@@ -0,0 +1,76 @@
+/* Check compatibility of CET-enabled executable with dlopened legacy
+ shared object.
+ Copyright (C) 2019 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/>. */
+
+#include <dlfcn.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+
+static void
+do_test_1 (const char *modname, bool fail)
+{
+ int (*fp) (void);
+ void *h;
+
+ h = dlopen (modname, RTLD_LAZY);
+ if (h == NULL)
+ {
+ if (fail)
+ {
+ const char *err = dlerror ();
+ if (strstr (err, "shadow stack isn't enabled") == NULL)
+ {
+ printf ("incorrect dlopen '%s' error: %s\n", modname,
+ dlerror ());
+ exit (1);
+ }
+
+ return;
+ }
+
+ printf ("cannot open '%s': %s\n", modname, dlerror ());
+ exit (1);
+ }
+
+ fp = dlsym (h, "test");
+ if (fp == NULL)
+ {
+ printf ("cannot get symbol 'test': %s\n", dlerror ());
+ exit (1);
+ }
+
+ if (fp () != 0)
+ {
+ puts ("test () != 0");
+ exit (1);
+ }
+
+ dlclose (h);
+}
+
+static int
+do_test (void)
+{
+ do_test_1 ("tst-cet-legacy-mod-5a.so", true);
+ do_test_1 ("tst-cet-legacy-mod-5b.so", false);
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/x86/tst-cet-legacy-5a.c b/sysdeps/x86/tst-cet-legacy-5a.c
new file mode 100644
index 0000000000..fc5a609dff
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-5a.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-5.c"
diff --git a/sysdeps/x86/tst-cet-legacy-5b.c b/sysdeps/x86/tst-cet-legacy-5b.c
new file mode 100644
index 0000000000..fc5a609dff
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-5b.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-5.c"
diff --git a/sysdeps/x86/tst-cet-legacy-6.c b/sysdeps/x86/tst-cet-legacy-6.c
new file mode 100644
index 0000000000..9151225264
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-6.c
@@ -0,0 +1,76 @@
+/* Check compatibility of CET-enabled executable with dlopened legacy
+ shared object.
+ Copyright (C) 2019 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/>. */
+
+#include <dlfcn.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+
+static void
+do_test_1 (const char *modname, bool fail)
+{
+ int (*fp) (void);
+ void *h;
+
+ h = dlopen (modname, RTLD_LAZY);
+ if (h == NULL)
+ {
+ if (fail)
+ {
+ const char *err = dlerror ();
+ if (strstr (err, "shadow stack isn't enabled") == NULL)
+ {
+ printf ("incorrect dlopen '%s' error: %s\n", modname,
+ dlerror ());
+ exit (1);
+ }
+
+ return;
+ }
+
+ printf ("cannot open '%s': %s\n", modname, dlerror ());
+ exit (1);
+ }
+
+ fp = dlsym (h, "test");
+ if (fp == NULL)
+ {
+ printf ("cannot get symbol 'test': %s\n", dlerror ());
+ exit (1);
+ }
+
+ if (fp () != 0)
+ {
+ puts ("test () != 0");
+ exit (1);
+ }
+
+ dlclose (h);
+}
+
+static int
+do_test (void)
+{
+ do_test_1 ("tst-cet-legacy-mod-6a.so", true);
+ do_test_1 ("tst-cet-legacy-mod-6b.so", false);
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/x86/tst-cet-legacy-6a.c b/sysdeps/x86/tst-cet-legacy-6a.c
new file mode 100644
index 0000000000..2d1546d36b
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-6a.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-6.c"
diff --git a/sysdeps/x86/tst-cet-legacy-6b.c b/sysdeps/x86/tst-cet-legacy-6b.c
new file mode 100644
index 0000000000..2d1546d36b
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-6b.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-6.c"
diff --git a/sysdeps/x86/tst-cet-legacy-mod-5.c b/sysdeps/x86/tst-cet-legacy-mod-5.c
new file mode 100644
index 0000000000..3c1071c2ef
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-5.c
@@ -0,0 +1,31 @@
+/* Check compatibility of CET-enabled executable with dlopened legacy
+ shared object.
+ Copyright (C) 2019 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/>. */
+
+#include <error.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+extern void foo (void);
+
+int
+test (void)
+{
+ foo ();
+ return 0;
+}
diff --git a/sysdeps/x86/tst-cet-legacy-mod-5a.c b/sysdeps/x86/tst-cet-legacy-mod-5a.c
new file mode 100644
index 0000000000..daa43e4e8d
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-5a.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-mod-5.c"
diff --git a/sysdeps/x86/tst-cet-legacy-mod-5b.c b/sysdeps/x86/tst-cet-legacy-mod-5b.c
new file mode 100644
index 0000000000..daa43e4e8d
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-5b.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-mod-5.c"
diff --git a/sysdeps/x86/tst-cet-legacy-mod-5c.c b/sysdeps/x86/tst-cet-legacy-mod-5c.c
new file mode 100644
index 0000000000..e529a42ac0
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-5c.c
@@ -0,0 +1,36 @@
+/* Check compatibility of CET-enabled executable with dlopened legacy
+ shared object.
+ Copyright (C) 2019 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/>. */
+
+#include <stdlib.h>
+
+static int called = 0;
+
+static void
+__attribute__ ((constructor))
+init (void)
+{
+ called = 1;
+}
+
+void
+foo (void)
+{
+ if (!called)
+ abort ();
+}
diff --git a/sysdeps/x86/tst-cet-legacy-mod-6.c b/sysdeps/x86/tst-cet-legacy-mod-6.c
new file mode 100644
index 0000000000..3c1071c2ef
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-6.c
@@ -0,0 +1,31 @@
+/* Check compatibility of CET-enabled executable with dlopened legacy
+ shared object.
+ Copyright (C) 2019 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/>. */
+
+#include <error.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+extern void foo (void);
+
+int
+test (void)
+{
+ foo ();
+ return 0;
+}
diff --git a/sysdeps/x86/tst-cet-legacy-mod-6a.c b/sysdeps/x86/tst-cet-legacy-mod-6a.c
new file mode 100644
index 0000000000..c89b8fe8ff
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-6a.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-mod-6.c"
diff --git a/sysdeps/x86/tst-cet-legacy-mod-6b.c b/sysdeps/x86/tst-cet-legacy-mod-6b.c
new file mode 100644
index 0000000000..c89b8fe8ff
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-6b.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-mod-6.c"
diff --git a/sysdeps/x86/tst-cet-legacy-mod-6c.c b/sysdeps/x86/tst-cet-legacy-mod-6c.c
new file mode 100644
index 0000000000..e529a42ac0
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-6c.c
@@ -0,0 +1,36 @@
+/* Check compatibility of CET-enabled executable with dlopened legacy
+ shared object.
+ Copyright (C) 2019 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/>. */
+
+#include <stdlib.h>
+
+static int called = 0;
+
+static void
+__attribute__ ((constructor))
+init (void)
+{
+ called = 1;
+}
+
+void
+foo (void)
+{
+ if (!called)
+ abort ();
+}
diff --git a/sysdeps/x86/tst-cet-legacy-mod-6d.c b/sysdeps/x86/tst-cet-legacy-mod-6d.c
new file mode 100644
index 0000000000..eb233a1d10
--- /dev/null
+++ b/sysdeps/x86/tst-cet-legacy-mod-6d.c
@@ -0,0 +1 @@
+#include "tst-cet-legacy-mod-6c.c"