From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f171.google.com (mail-lb0-f171.google.com [209.85.217.171]) by kanga.kvack.org (Postfix) with ESMTP id 4B1426B0036 for ; Thu, 24 Jul 2014 12:50:55 -0400 (EDT) Received: by mail-lb0-f171.google.com with SMTP id l4so2524694lbv.30 for ; Thu, 24 Jul 2014 09:50:54 -0700 (PDT) Received: from mail-lb0-x234.google.com (mail-lb0-x234.google.com [2a00:1450:4010:c04::234]) by mx.google.com with ESMTPS id cr4si13733896lad.111.2014.07.24.09.50.52 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 24 Jul 2014 09:50:53 -0700 (PDT) Received: by mail-lb0-f180.google.com with SMTP id v6so2528085lbi.11 for ; Thu, 24 Jul 2014 09:50:52 -0700 (PDT) Message-Id: <20140724165047.437075575@openvz.org> Date: Thu, 24 Jul 2014 20:46:58 +0400 From: Cyrill Gorcunov Subject: [rfc 1/4] mm: Introduce may_adjust_brk helper References: <20140724164657.452106845@openvz.org> Content-Disposition: inline; filename=prctl-add-may_adjust_brk Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: gorcunov@openvz.org, keescook@chromium.org, tj@kernel.org, akpm@linux-foundation.org, avagin@openvz.org, ebiederm@xmission.com, hpa@zytor.com, serge.hallyn@canonical.com, xemul@parallels.com, segoon@openwall.com, kamezawa.hiroyu@jp.fujitsu.com, mtk.manpages@gmail.com, jln@google.com To eliminate code duplication lets introduce may_adjust_brk helper which we will use in brk() and prctl() syscalls. Signed-off-by: Cyrill Gorcunov Cc: Kees Cook Cc: Tejun Heo Cc: Andrew Morton Cc: Andrew Vagin Cc: Eric W. Biederman Cc: H. Peter Anvin Cc: Serge Hallyn Cc: Pavel Emelyanov Cc: Vasiliy Kulikov Cc: KAMEZAWA Hiroyuki Cc: Michael Kerrisk Cc: Julien Tinnes --- include/linux/mm.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) Index: linux-2.6.git/include/linux/mm.h =================================================================== --- linux-2.6.git.orig/include/linux/mm.h +++ linux-2.6.git/include/linux/mm.h @@ -18,6 +18,7 @@ #include #include #include +#include struct mempolicy; struct anon_vma; @@ -1780,6 +1781,19 @@ extern struct vm_area_struct *copy_vma(s bool *need_rmap_locks); extern void exit_mmap(struct mm_struct *); +static inline int may_adjust_brk(unsigned long rlim, + unsigned long new_brk, + unsigned long start_brk, + unsigned long end_data, + unsigned long start_data) +{ + if (rlim < RLIMIT_DATA) { + if (((new_brk - start_brk) + (end_data - start_data)) > rlim) + return -ENOSPC; + } + return 0; +} + extern int mm_take_all_locks(struct mm_struct *mm); extern void mm_drop_all_locks(struct mm_struct *mm); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org