[glibc] elf: Add a test for PT_LOAD segments with p_align == 1 [BZ #28688]

[H.J. Lu <hjl@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=e4c9268d154ff11c070eba4791d33bd3a5875bca

commit e4c9268d154ff11c070eba4791d33bd3a5875bca
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Tue Dec 21 12:25:20 2021 -0800

    elf: Add a test for PT_LOAD segments with p_align == 1 [BZ #28688]
    
    Add tst-p_alignmod2-edit to edit the copy of tst-p_alignmod-base.so to
    set p_align of the first PT_LOAD segment to 1 and verify that the shared
    library can be loaded normally.
    
    Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Diff:
---
 elf/Makefile               | 13 +++++++++++++
 elf/tst-p_align2.c         | 27 +++++++++++++++++++++++++++
 elf/tst-p_alignmod2-edit.c | 27 +++++++++++++++++++++++++++
 3 files changed, 67 insertions(+)

diff --git a/elf/Makefile b/elf/Makefile
index 1758259075..687b913a53 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -414,7 +414,9 @@ tests += \
   tst-noload \
   tst-null-argv \
   tst-p_alignmod1-edit \
+  tst-p_alignmod2-edit \
   tst-p_align1 \
+  tst-p_align2 \
   tst-relsort1 \
   tst-ro-dynamic \
   tst-rtld-run-static \
@@ -2609,3 +2611,14 @@ $(objpfx)tst-p_alignmod1.so: $(objpfx)tst-p_alignmod1-edit \
 	cp $(objpfx)tst-p_alignmod-base.so $@
 	$(test-wrapper-env) $(run-program-env) $(rtld-prefix) \
 	  $(objpfx)tst-p_alignmod1-edit $@
+
+$(objpfx)tst-p_align2: $(objpfx)tst-p_alignmod2.so
+
+# Make a copy of tst-p_alignmod-base.so and update p_align of the first
+# PT_LOAD segment.
+$(objpfx)tst-p_alignmod2.so: $(objpfx)tst-p_alignmod2-edit \
+			     $(objpfx)tst-p_alignmod-base.so
+	rm -f $@
+	cp $(objpfx)tst-p_alignmod-base.so $@
+	$(test-wrapper-env) $(run-program-env) $(rtld-prefix) \
+	  $(objpfx)tst-p_alignmod2-edit $@
diff --git a/elf/tst-p_align2.c b/elf/tst-p_align2.c
new file mode 100644
index 0000000000..961c7fbbf1
--- /dev/null
+++ b/elf/tst-p_align2.c
@@ -0,0 +1,27 @@
+/* Check different alignments of PT_LOAD segments in a shared library.
+   Copyright (C) 2022 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 "tst-p_align.h"
+
+static int
+do_test (void)
+{
+  return do_load_test ();
+}
+
+#include <support/test-driver.c>
diff --git a/elf/tst-p_alignmod2-edit.c b/elf/tst-p_alignmod2-edit.c
new file mode 100644
index 0000000000..4c2ae65b4e
--- /dev/null
+++ b/elf/tst-p_alignmod2-edit.c
@@ -0,0 +1,27 @@
+/* Set p_align of the first PT_LOAD segment to 1.
+   Copyright (C) 2022 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 "tst-elf-edit.h"
+
+/* Set p_align to 1.  */
+
+static size_t
+update_p_align (size_t p_align __attribute__ ((unused)))
+{
+  return 1;
+}