From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030997Ab3HITv4 (ORCPT ); Fri, 9 Aug 2013 15:51:56 -0400 Received: from usmamail.tilera.com ([12.216.194.151]:62763 "EHLO USMAMAIL.TILERA.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030908Ab3HITvw (ORCPT ); Fri, 9 Aug 2013 15:51:52 -0400 Message-ID: <201308091951.r79JppCI030998@farm-0021.internal.tilera.com> From: Tony Lu Date: Fri, 9 Aug 2013 15:45:24 -0400 Subject: [PATCH] tile: support ASLR fully To: , Jiri Kosina MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With this change, tile Linux now supports address-space layout randomization for shared objects, stack, heap and vdso. Signed-off-by: Tony Lu Signed-off-by: Chris Metcalf --- arch/tile/include/asm/elf.h | 4 ++++ arch/tile/mm/mmap.c | 20 ++++++++++++++++++-- 2 files changed, 22 insertions(+), 2 deletions(-) diff --git a/arch/tile/include/asm/elf.h b/arch/tile/include/asm/elf.h index 31d854f..e1da88e 100644 --- a/arch/tile/include/asm/elf.h +++ b/arch/tile/include/asm/elf.h @@ -137,6 +137,10 @@ do { \ NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_BASE); \ } while (0) +struct mm_struct; +extern unsigned long arch_randomize_brk(struct mm_struct *mm); +#define arch_randomize_brk arch_randomize_brk + #ifdef CONFIG_COMPAT #define COMPAT_ELF_PLATFORM "tilegx-m32" diff --git a/arch/tile/mm/mmap.c b/arch/tile/mm/mmap.c index d67d91e..b3686ce 100644 --- a/arch/tile/mm/mmap.c +++ b/arch/tile/mm/mmap.c @@ -58,16 +58,32 @@ void arch_pick_mmap_layout(struct mm_struct *mm) #else int is_32bit = 0; #endif + unsigned long random_factor = 0UL; + + if (current->flags & PF_RANDOMIZE) { + random_factor = get_random_int(); + random_factor = random_factor << PAGE_SHIFT; + if (is_32bit) + random_factor &= 0xfffffful; + else + random_factor &= 0xffffffful; + } /* * Use standard layout if the expected stack growth is unlimited * or we are running native 64 bits. */ - if (!is_32bit || rlimit(RLIMIT_STACK) == RLIM_INFINITY) { - mm->mmap_base = TASK_UNMAPPED_BASE; + if (rlimit(RLIMIT_STACK) == RLIM_INFINITY) { + mm->mmap_base = TASK_UNMAPPED_BASE + random_factor; mm->get_unmapped_area = arch_get_unmapped_area; } else { mm->mmap_base = mmap_base(mm); mm->get_unmapped_area = arch_get_unmapped_area_topdown; } } + +unsigned long arch_randomize_brk(struct mm_struct *mm) +{ + unsigned long range_end = mm->brk + 0x02000000; + return randomize_range(mm->brk, range_end, 0) ? : mm->brk; +} -- 1.8.3.1