From patchwork Sun Jul 24 15:30:24 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Pitre X-Patchwork-Id: 72676 Delivered-To: patch@linaro.org Received: by 10.140.29.52 with SMTP id a49csp744031qga; Sun, 24 Jul 2016 08:32:16 -0700 (PDT) X-Received: by 10.98.157.12 with SMTP id i12mr22460104pfd.164.1469374329082; Sun, 24 Jul 2016 08:32:09 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id i8si28543393pfk.43.2016.07.24.08.32.08; Sun, 24 Jul 2016 08:32:09 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752655AbcGXPbg (ORCPT + 29 others); Sun, 24 Jul 2016 11:31:36 -0400 Received: from alt32.smtp-out.videotron.ca ([24.53.0.21]:54525 "EHLO alt32.smtp-out.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752086AbcGXPak (ORCPT ); Sun, 24 Jul 2016 11:30:40 -0400 Received: from yoda.home ([96.23.157.65]) by Videotron with SMTP id RLMUbeEZXYOXTRLMVbJ3Gt; Sun, 24 Jul 2016 11:30:39 -0400 X-Authority-Analysis: v=2.1 cv=Gfm35VjL c=1 sm=1 tr=0 a=keA3yYpnlypCNW5BNWqu+w==:117 a=keA3yYpnlypCNW5BNWqu+w==:17 a=L9H7d07YOLsA:10 a=9cW_t1CCXrUA:10 a=s5jvgZ67dGcA:10 a=cAmyUtKerLwA:10 a=KKAkSRfTAAAA:8 a=tBb2bbeoAAAA:8 a=R5CuANmm5DveqMR5uOoA:9 a=cvBusfyB2V15izCimMoJ:22 a=Oj-tNtZlA1e06AYgeCfH:22 Received: from xanadu.home (xanadu.home [192.168.2.2]) by yoda.home (Postfix) with ESMTP id 49D4E2DA06A4; Sun, 24 Jul 2016 11:30:36 -0400 (EDT) From: Nicolas Pitre To: Greg Ungerer , linux-fsdevel@vger.kernel.org Cc: Alan Cox , Alexander Viro , David Howells , linux-arm-kernel@lists.infradead.org, linux-m68k@lists.linux-m68k.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 10/15] binfmt_flat: update libraries' data segment pointer with userspace accessors Date: Sun, 24 Jul 2016 11:30:24 -0400 Message-Id: <1469374229-21585-11-git-send-email-nicolas.pitre@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1469374229-21585-1-git-send-email-nicolas.pitre@linaro.org> References: <1469374229-21585-1-git-send-email-nicolas.pitre@linaro.org> X-CMAE-Envelope: MS4wfOhT0Vew7D3vash1skWf/VA7GHtJiRcwfax88o8+XuGJrXzoXt/8eciNThjV8YWOFgtFiiiU77L+wqHJp+ZzZ6vMKrDxDRUQ12mqURgvudwXU/tVY/Uy Nh5EoBTaH4uDTVd+d30sKDOiSCi1x5HjoY65h6Uv72Oq1XyvQuIDWkQDtLvZiCeyRP9X8dQp9jd3U38Rss6YTeg3Hp5XhxfjkGKaDnlotP7V0pHrNnI9Qkbt m9EvEaqkk7Gma+MbKrWIiNJ2Q+3ghj0M5VvJry/8X9zf7R1N/k/lYErp0sFiim3N8sJ8gahzVUT3uj9nN3dticM8vLbGLoZ6VKj1/dphptH+uInArk8//7ZX BBJXkhhlbB8PuSQOd6VppoHK7pBO4834cDKJzChRqW6N+BcXVW9w1HNZ+KwRRbx9ymEIzbfucBC0RbtJTemTf0WUCNrpUAVYJlY02cF31YsFqETWT38= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is needed on systems with a MMU. This also gets rid of the strangest C code I've seen lateli i.e. an integer indexed with a pointer value within square brackets. That really looked backwards. Signed-off-by: Nicolas Pitre Reviewed-by: Greg Ungerer --- fs/binfmt_flat.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) -- 2.7.4 diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index 92c1530a2c..aa7971ce6a 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -894,12 +894,19 @@ static int load_flat_binary(struct linux_binprm *bprm) return res; /* Update data segment pointers for all libraries */ - for (i = 0; i < MAX_SHARED_LIBS; i++) - if (libinfo.lib_list[i].loaded) - for (j = 0; j < MAX_SHARED_LIBS; j++) - (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] = - (libinfo.lib_list[j].loaded) ? - libinfo.lib_list[j].start_data : UNLOADED_LIB; + for (i = 0; i < MAX_SHARED_LIBS; i++) { + if (!libinfo.lib_list[i].loaded) + continue; + for (j = 0; j < MAX_SHARED_LIBS; j++) { + unsigned long val = libinfo.lib_list[j].loaded ? + libinfo.lib_list[j].start_data : UNLOADED_LIB; + unsigned long __user *p = (unsigned long __user *) + libinfo.lib_list[i].start_data; + p -= j + 1; + if (put_user(val, p)) + return -EFAULT; + } + } install_exec_creds(bprm);