From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161192Ab3LFNAT (ORCPT ); Fri, 6 Dec 2013 08:00:19 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:43680 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161175Ab3LFNAQ (ORCPT ); Fri, 6 Dec 2013 08:00:16 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Anton Blanchard , Benjamin Herrenschmidt , Luis Henriques Subject: [PATCH 3.11 035/272] powerpc: ppc64 address space capped at 32TB, mmap randomisation disabled Date: Fri, 6 Dec 2013 12:55:24 +0000 Message-Id: <1386334761-25517-36-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1386334761-25517-1-git-send-email-luis.henriques@canonical.com> References: <1386334761-25517-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.11.10.1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Anton Blanchard commit 5a049f14902982c26538250bdc8d54156d357252 upstream. Commit fba2369e6ceb (mm: use vm_unmapped_area() on powerpc architecture) has a bug in slice_scan_available() where we compare an unsigned long (high_slices) against a shifted int. As a result, comparisons against the top 32 bits of high_slices (representing the top 32TB) always returns 0 and the top of our mmap region is clamped at 32TB This also breaks mmap randomisation since the randomised address is always up near the top of the address space and it gets clamped down to 32TB. Signed-off-by: Anton Blanchard Acked-by: Michel Lespinasse Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Luis Henriques --- arch/powerpc/mm/slice.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c index 3e99c14..7ce9cf3 100644 --- a/arch/powerpc/mm/slice.c +++ b/arch/powerpc/mm/slice.c @@ -258,7 +258,7 @@ static bool slice_scan_available(unsigned long addr, slice = GET_HIGH_SLICE_INDEX(addr); *boundary_addr = (slice + end) ? ((slice + end) << SLICE_HIGH_SHIFT) : SLICE_LOW_TOP; - return !!(available.high_slices & (1u << slice)); + return !!(available.high_slices & (1ul << slice)); } } -- 1.8.3.2