glibc/elf/tst-big-note-lib.S
Florian Weimer c259196b50 elf/tst-big-note: Improve accuracy of test [BZ #20419]
It is possible that the link editor injects an allocated ABI tag note
before the artificial, allocated large note in the test.  Note parsing
in open_verify stops when the first ABI tag note is encountered, so if
the ABI tag note comes first, the problematic code is not actually
exercised.

Also tweak the artificial note so that it is a syntactically valid
4-byte aligned note, in case the link editor tries to parse notes and
process them.

Improves the testing part of commit 0065aaaaae.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2019-03-01 18:53:42 +01:00

33 lines
1.3 KiB
ArmAsm

/* Bug 20419: test for stack overflow in elf/dl-load.c open_verify()
Copyright (C) 2018-2019 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/>. */
/* This creates a .so with 8MiB PT_NOTE segment.
On a typical Linux system with 8MiB "ulimit -s", that was enough
to trigger stack overflow in open_verify. */
#define NOTE_SIZE 8*1024*1024
.pushsection .note.big,"a"
.balign 4
.long 5 /* n_namesz. Length of "GLIBC". */
.long NOTE_SIZE /* n_descsz. */
.long 0 /* n_type. */
.ascii "GLIBC\0\0\0" /* Name and alignment to four bytes. */
.fill NOTE_SIZE, 1, 0
.popsection