From patchwork Mon Jul 18 03:31:52 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Pitre X-Patchwork-Id: 72182 Delivered-To: patch@linaro.org Received: by 10.140.29.52 with SMTP id a49csp197789qga; Sun, 17 Jul 2016 20:33:48 -0700 (PDT) X-Received: by 10.98.200.29 with SMTP id z29mr42583783pff.143.1468812828702; Sun, 17 Jul 2016 20:33:48 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id j2si24252400pan.178.2016.07.17.20.33.48; Sun, 17 Jul 2016 20:33:48 -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 S1751759AbcGRDcb (ORCPT + 29 others); Sun, 17 Jul 2016 23:32:31 -0400 Received: from alt22.smtp-out.videotron.ca ([70.80.0.73]:38388 "EHLO alt22.smtp-out.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751499AbcGRDcM (ORCPT ); Sun, 17 Jul 2016 23:32:12 -0400 Received: from yoda.home ([96.23.157.65]) by Videotron with SMTP id OzHubq8nQzCgpOzHvbWVHR; Sun, 17 Jul 2016 23:32:11 -0400 X-Authority-Analysis: v=2.1 cv=QfzGxpvv 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=6cg3P4PxVmMxiyGXiDwA:9 a=cvBusfyB2V15izCimMoJ:22 Received: from xanadu.home (xanadu.home [192.168.2.2]) by yoda.home (Postfix) with ESMTP id A73C82DA0684; Sun, 17 Jul 2016 23:32:08 -0400 (EDT) From: Nicolas Pitre To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Alexander Viro , David Howells , Greg Ungerer Subject: [PATCH v2 06/10] binfmt_flat: use proper user space accessors with old relocs code Date: Sun, 17 Jul 2016 23:31:52 -0400 Message-Id: <1468812716-30537-7-git-send-email-nicolas.pitre@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1468812716-30537-1-git-send-email-nicolas.pitre@linaro.org> References: <1468812716-30537-1-git-send-email-nicolas.pitre@linaro.org> X-CMAE-Envelope: MS4wfLTO4D5rJPG8LnbS6bGm6r+4QNJFMocQ/hWJzvaO4cBybOwgj2Dxwp9us8tqK8VeSatyu5YhlRuhadwq2h7cFXD5PNaoz2jQXDG2aIeyBpEqqKrX6hiP BSdoua5S1BUYwUgUn/Ngr4FVJx7uFnbviwFnePjD2+HzuOgkiw0xW2hqIaFcqM3htC2vYegiMd3hKU6JbLQPdhzSgj4IWAVmHjr+ZP1Jhupf5ET2mp4dn+9v MI5BI6j3QdtQOys4vydGAUM53lLhHW1UbNUTKSRN3lih2h9b+Zhe3pj6cHx6BoQQ/4pEoFPN19BewF2efJUwJg== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Nicolas Pitre --- fs/binfmt_flat.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) -- 2.7.4 diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index fc0ee3ed5d..c85f8f1239 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -394,38 +394,41 @@ static void old_reloc(unsigned long rl) static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; #endif flat_v2_reloc_t r; - unsigned long *ptr; + unsigned long __user *ptr; + unsigned long val; r.value = rl; #if defined(CONFIG_COLDFIRE) - ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset); + ptr = (unsigned long __user *)(current->mm->start_code + r.reloc.offset); #else - ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset); + ptr = (unsigned long __user *)(current->mm->start_data + r.reloc.offset); #endif + __get_user(val, ptr); #ifdef DEBUG printk("Relocation of variable at DATASEG+%x " "(address %p, currently %lx) into segment %s\n", - r.reloc.offset, ptr, *ptr, segment[r.reloc.type]); + r.reloc.offset, ptr, val, segment[r.reloc.type]); #endif switch (r.reloc.type) { case OLD_FLAT_RELOC_TYPE_TEXT: - *ptr += current->mm->start_code; + val += current->mm->start_code; break; case OLD_FLAT_RELOC_TYPE_DATA: - *ptr += current->mm->start_data; + val += current->mm->start_data; break; case OLD_FLAT_RELOC_TYPE_BSS: - *ptr += current->mm->end_data; + val += current->mm->end_data; break; default: printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type); break; } + __put_user(val, ptr); #ifdef DEBUG - printk("Relocation became %lx\n", *ptr); + printk("Relocation became %lx\n", val); #endif } @@ -788,8 +791,13 @@ static int load_flat_file(struct linux_binprm * bprm, } } } else { - for (i=0; i < relocs; i++) - old_reloc(ntohl(reloc[i])); + for (i=0; i < relocs; i++) { + unsigned long relval; + if (get_user(relval, reloc + i)) + return -EFAULT; + relval = ntohl(relval); + old_reloc(relval); + } } flush_icache_range(start_code, end_code);