From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758647Ab3IBI4m (ORCPT ); Mon, 2 Sep 2013 04:56:42 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:37918 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758596Ab3IBIz5 (ORCPT ); Mon, 2 Sep 2013 04:55:57 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Radu Caragea , Andrew Morton , Michel Lespinasse , Oleg Nesterov , Rik van Riel , Ingo Molnar , Adrian Sendroiu , Greg KH , Kamal Mostafa , Linus Torvalds , Luis Henriques Subject: [PATCH 58/58] x86 get_unmapped_area: Access mmap_legacy_base through mm_struct member Date: Mon, 2 Sep 2013 09:54:43 +0100 Message-Id: <1378112083-9475-59-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1378112083-9475-1-git-send-email-luis.henriques@canonical.com> References: <1378112083-9475-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.21 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Radu Caragea commit 41aacc1eea645c99edbe8fbcf78a97dc9b862adc upstream. This is the updated version of df54d6fa5427 ("x86 get_unmapped_area(): use proper mmap base for bottom-up direction") that only randomizes the mmap base address once. Signed-off-by: Radu Caragea Reported-and-tested-by: Jeff Shorey Cc: Andrew Morton Cc: Michel Lespinasse Cc: Oleg Nesterov Cc: Rik van Riel Cc: Ingo Molnar Cc: Adrian Sendroiu Cc: Greg KH Cc: Kamal Mostafa Signed-off-by: Linus Torvalds Signed-off-by: Luis Henriques --- arch/x86/kernel/sys_x86_64.c | 2 +- arch/x86/mm/mmap.c | 6 ++++-- include/linux/mm_types.h | 1 + 3 files changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index b4d3c39..51534ef 100644 --- a/arch/x86/kernel/sys_x86_64.c +++ b/arch/x86/kernel/sys_x86_64.c @@ -115,7 +115,7 @@ static void find_start_end(unsigned long flags, unsigned long *begin, *begin = new_begin; } } else { - *begin = TASK_UNMAPPED_BASE; + *begin = current->mm->mmap_legacy_base; *end = TASK_SIZE; } } diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c index 845df68..5c1ae28 100644 --- a/arch/x86/mm/mmap.c +++ b/arch/x86/mm/mmap.c @@ -112,12 +112,14 @@ static unsigned long mmap_legacy_base(void) */ void arch_pick_mmap_layout(struct mm_struct *mm) { + mm->mmap_legacy_base = mmap_legacy_base(); + mm->mmap_base = mmap_base(); + if (mmap_is_legacy()) { - mm->mmap_base = mmap_legacy_base(); + mm->mmap_base = mm->mmap_legacy_base; mm->get_unmapped_area = arch_get_unmapped_area; mm->unmap_area = arch_unmap_area; } else { - mm->mmap_base = mmap_base(); mm->get_unmapped_area = arch_get_unmapped_area_topdown; mm->unmap_area = arch_unmap_area_topdown; } diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 704a626..b5bea2f 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -307,6 +307,7 @@ struct mm_struct { void (*unmap_area) (struct mm_struct *mm, unsigned long addr); #endif unsigned long mmap_base; /* base of mmap area */ + unsigned long mmap_legacy_base; /* base of mmap area in bottom-up allocations */ unsigned long task_size; /* size of task vm space */ unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */ unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */ -- 1.8.3.2