Re: [PATCH v5 2/2] Add a testcase to check alignment of PT_LOAD segment

["H.J. Lu" <hjl.tools@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 6359 bytes --]

On Fri, Dec 10, 2021 at 5:48 AM Adhemerval Zanella
<adhemerval.zanella@linaro.org> wrote:
>
>
>
> On 10/12/2021 09:39, Rongwei Wang via Libc-alpha wrote:
> > From: "H.J. Lu" <hjl.tools@gmail.com>
> >
> > This patch adds a testcase for PT_LOAD segment to check it is
> > properly aligned when the alignment > the page size.
> >
> > Signed-off-by: "H.J. Lu" <hjl.tools@gmail.com>
> > Signed-off-by: Rongwei Wang <rongwei.wang@linux.alibaba.com>
> > ---
> >  elf/Makefile        | 14 ++++++++++++--
> >  elf/tst-align3.c    | 37 +++++++++++++++++++++++++++++++++++++
> >  elf/tst-alignmod3.c | 31 +++++++++++++++++++++++++++++++
> >  3 files changed, 80 insertions(+), 2 deletions(-)
> >  create mode 100644 elf/tst-align3.c
> >  create mode 100644 elf/tst-alignmod3.c
> >
> > diff --git a/elf/Makefile b/elf/Makefile
> > index ef36008673..b16128ac8b 100644
> > --- a/elf/Makefile
> > +++ b/elf/Makefile
> > @@ -207,7 +207,7 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \
> >        tst-tls4 tst-tls5 \
> >        tst-tls10 tst-tls11 tst-tls12 tst-tls13 tst-tls14 tst-tls15 \
> >        tst-tls16 tst-tls17 tst-tls18 tst-tls19 tst-tls-dlinfo \
> > -      tst-align tst-align2 \
> > +      tst-align tst-align2 tst-align3 \
> >        tst-dlmodcount tst-dlopenrpath tst-deep1 \
> >        tst-dlmopen1 tst-dlmopen3 tst-dlmopen4 \
> >        unload3 unload4 unload5 unload6 unload7 unload8 tst-global1 order2 \
> > @@ -241,6 +241,9 @@ tests-internal += loadtest unload unload2 circleload1 \
> >  tests-container += tst-pldd tst-dlopen-tlsmodid-container \
> >    tst-dlopen-self-container tst-preload-pthread-libc
> >  test-srcs = tst-pathopt
> > +ifeq (yes,$(have-fpie))
> > +tests-pie += tst-align3
> > +endif
> >  selinux-enabled := $(shell cat /selinux/enforce 2> /dev/null)
> >  ifneq ($(selinux-enabled),1)
> >  tests-execstack-yes = tst-execstack tst-execstack-needed tst-execstack-prog
> > @@ -302,7 +305,7 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \
> >               circlemod3 circlemod3a \
> >               reldep8mod1 reldep8mod2 reldep8mod3 \
> >               reldep9mod1 reldep9mod2 reldep9mod3 \
> > -             tst-alignmod tst-alignmod2 \
> > +             tst-alignmod tst-alignmod2 tst-alignmod3 \
> >               $(modules-execstack-$(have-z-execstack)) \
> >               tst-dlopenrpathmod tst-deep1mod1 tst-deep1mod2 tst-deep1mod3 \
> >               tst-dlmopen1mod tst-auditmod1 \
> > @@ -1088,6 +1091,13 @@ CFLAGS-tst-alignmod.c += $(stack-align-test-flags)
> >  CFLAGS-tst-alignmod2.c += $(stack-align-test-flags)
> >  $(objpfx)tst-align.out: $(objpfx)tst-alignmod.so
> >  $(objpfx)tst-align2: $(objpfx)tst-alignmod2.so
> > +$(objpfx)tst-align3: $(objpfx)tst-alignmod3.so
> > +ifeq (yes,$(have-fpie))
> > +CFLAGS-tst-align3.c += $(PIE-ccflag)
> > +endif
> > +LDFLAGS-tst-align3 += -Wl,-z,max-page-size=0x200000
> > +LDFLAGS-tst-alignmod3.so += -Wl,-z,max-page-size=0x200000
> > +$(objpfx)tst-alignmod3.so: $(libsupport)
> >
> >  $(objpfx)unload3.out: $(objpfx)unload3mod1.so $(objpfx)unload3mod2.so \
> >                     $(objpfx)unload3mod3.so $(objpfx)unload3mod4.so
> > diff --git a/elf/tst-align3.c b/elf/tst-align3.c
> > new file mode 100644
> > index 0000000000..5697c0bbaf
> > --- /dev/null
> > +++ b/elf/tst-align3.c
> > @@ -0,0 +1,37 @@
> > +/* Check alignment of PT_LOAD segment in a shared library.
> > +   Copyright (C) 2021 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 <support/check.h>
> > +#include <tst-stack-align.h>
> > +
> > +#define ALIGN 0x200000
> > +
> > +int bar __attribute__ ((aligned (ALIGN))) = 1;
> > +
> > +extern int do_load_test (void);
> > +
> > +static int
> > +do_test (void)
> > +{
> > +  printf ("bar: %p\n", &bar);
> > +  TEST_VERIFY (is_aligned (&bar, ALIGN) == 0);
> > +
> > +  return do_load_test ();
> > +}
> > +
> > +#include <support/test-driver.c>
> > diff --git a/elf/tst-alignmod3.c b/elf/tst-alignmod3.c
> > new file mode 100644
> > index 0000000000..50ec08462c
> > --- /dev/null
> > +++ b/elf/tst-alignmod3.c
> > @@ -0,0 +1,31 @@
> > +/* Check alignment of PT_LOAD segment in a shared library.
> > +   Copyright (C) 2021 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 <support/check.h>
> > +#include <tst-stack-align.h>
> > +
> > +#define ALIGN 0x200000
>
> I think it should cover all possible pagesize we current support.  Maybe add
> a comment here or on Makefile about it.

Here is the v2 patch I added

/* This should cover all possible page sizes we currently support.  */

> > +
> > +int foo __attribute__ ((aligned (ALIGN))) = 1;
> > +
> > +void
> > +do_load_test (void)
> > +{
> > +  printf ("foo: %p\n", &foo);
> > +  TEST_VERIFY (is_aligned (&foo, ALIGN) == 0);
> > +}
> >



-- 
H.J.

[-- Attachment #2: v2-0001-Add-a-testcase-to-check-alignment-of-PT_LOAD-segm.patch --]
[-- Type: text/x-patch, Size: 5328 bytes --]

From f5d30f3be4261eb0340de050a5bba586fca55b4f Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 9 Dec 2021 07:01:33 -0800
Subject: [PATCH v2] Add a testcase to check alignment of PT_LOAD segment [BZ
 #28676]

---
 elf/Makefile        | 14 ++++++++++++--
 elf/tst-align3.c    | 37 +++++++++++++++++++++++++++++++++++++
 elf/tst-alignmod3.c | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 81 insertions(+), 2 deletions(-)
 create mode 100644 elf/tst-align3.c
 create mode 100644 elf/tst-alignmod3.c

diff --git a/elf/Makefile b/elf/Makefile
index ef36008673..b16128ac8b 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -207,7 +207,7 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \
 	 tst-tls4 tst-tls5 \
 	 tst-tls10 tst-tls11 tst-tls12 tst-tls13 tst-tls14 tst-tls15 \
 	 tst-tls16 tst-tls17 tst-tls18 tst-tls19 tst-tls-dlinfo \
-	 tst-align tst-align2 \
+	 tst-align tst-align2 tst-align3 \
 	 tst-dlmodcount tst-dlopenrpath tst-deep1 \
 	 tst-dlmopen1 tst-dlmopen3 tst-dlmopen4 \
 	 unload3 unload4 unload5 unload6 unload7 unload8 tst-global1 order2 \
@@ -241,6 +241,9 @@ tests-internal += loadtest unload unload2 circleload1 \
 tests-container += tst-pldd tst-dlopen-tlsmodid-container \
   tst-dlopen-self-container tst-preload-pthread-libc
 test-srcs = tst-pathopt
+ifeq (yes,$(have-fpie))
+tests-pie += tst-align3
+endif
 selinux-enabled := $(shell cat /selinux/enforce 2> /dev/null)
 ifneq ($(selinux-enabled),1)
 tests-execstack-yes = tst-execstack tst-execstack-needed tst-execstack-prog
@@ -302,7 +305,7 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \
 		circlemod3 circlemod3a \
 		reldep8mod1 reldep8mod2 reldep8mod3 \
 		reldep9mod1 reldep9mod2 reldep9mod3 \
-		tst-alignmod tst-alignmod2 \
+		tst-alignmod tst-alignmod2 tst-alignmod3 \
 		$(modules-execstack-$(have-z-execstack)) \
 		tst-dlopenrpathmod tst-deep1mod1 tst-deep1mod2 tst-deep1mod3 \
 		tst-dlmopen1mod tst-auditmod1 \
@@ -1088,6 +1091,13 @@ CFLAGS-tst-alignmod.c += $(stack-align-test-flags)
 CFLAGS-tst-alignmod2.c += $(stack-align-test-flags)
 $(objpfx)tst-align.out: $(objpfx)tst-alignmod.so
 $(objpfx)tst-align2: $(objpfx)tst-alignmod2.so
+$(objpfx)tst-align3: $(objpfx)tst-alignmod3.so
+ifeq (yes,$(have-fpie))
+CFLAGS-tst-align3.c += $(PIE-ccflag)
+endif
+LDFLAGS-tst-align3 += -Wl,-z,max-page-size=0x200000
+LDFLAGS-tst-alignmod3.so += -Wl,-z,max-page-size=0x200000
+$(objpfx)tst-alignmod3.so: $(libsupport)
 
 $(objpfx)unload3.out: $(objpfx)unload3mod1.so $(objpfx)unload3mod2.so \
 		      $(objpfx)unload3mod3.so $(objpfx)unload3mod4.so
diff --git a/elf/tst-align3.c b/elf/tst-align3.c
new file mode 100644
index 0000000000..5697c0bbaf
--- /dev/null
+++ b/elf/tst-align3.c
@@ -0,0 +1,37 @@
+/* Check alignment of PT_LOAD segment in a shared library.
+   Copyright (C) 2021 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 <support/check.h>
+#include <tst-stack-align.h>
+
+#define ALIGN 0x200000
+
+int bar __attribute__ ((aligned (ALIGN))) = 1;
+
+extern int do_load_test (void);
+
+static int
+do_test (void)
+{
+  printf ("bar: %p\n", &bar);
+  TEST_VERIFY (is_aligned (&bar, ALIGN) == 0);
+
+  return do_load_test ();
+}
+
+#include <support/test-driver.c>
diff --git a/elf/tst-alignmod3.c b/elf/tst-alignmod3.c
new file mode 100644
index 0000000000..0d33f2379d
--- /dev/null
+++ b/elf/tst-alignmod3.c
@@ -0,0 +1,32 @@
+/* Check alignment of PT_LOAD segment in a shared library.
+   Copyright (C) 2021 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 <support/check.h>
+#include <tst-stack-align.h>
+
+/* This should cover all possible page sizes we currently support.  */
+#define ALIGN 0x200000
+
+int foo __attribute__ ((aligned (ALIGN))) = 1;
+
+void
+do_load_test (void)
+{
+  printf ("foo: %p\n", &foo);
+  TEST_VERIFY (is_aligned (&foo, ALIGN) == 0);
+}
-- 
2.33.1