From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751693AbcGTEXJ (ORCPT ); Wed, 20 Jul 2016 00:23:09 -0400 Received: from alt22.smtp-out.videotron.ca ([70.80.0.73]:58001 "EHLO alt22.smtp-out.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751425AbcGTEUt (ORCPT ); Wed, 20 Jul 2016 00:20:49 -0400 X-Authority-Analysis: v=2.1 cv=L469O7n8 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=yY8BnGvKRsEhquZvXpQA:9 a=cvBusfyB2V15izCimMoJ:22 a=Oj-tNtZlA1e06AYgeCfH:22 From: Nicolas Pitre To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Alexander Viro , David Howells , Greg Ungerer Subject: [PATCH v3 08/12] binfmt_flat: use proper user space accessors with old relocs code Date: Wed, 20 Jul 2016 00:20:20 -0400 Message-Id: <1468988424-32671-9-git-send-email-nicolas.pitre@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1468988424-32671-1-git-send-email-nicolas.pitre@linaro.org> References: <1468988424-32671-1-git-send-email-nicolas.pitre@linaro.org> X-CMAE-Envelope: MS4wfBdCcepaGrIeqyRj6nWFfGbZPiESvWc6SZ/fZR4gIvE33QmA9HVbnliLgp8MK+hlc5Icx38cFA+zEBxAuDMIm4iYwgEZpBDl2/plp5LbWZhgX93iaX9V vDlCaRqg62c0nmw1jfvCQqjg7R2GwQKvF978st6VvtFqTID9IP4uvtP+8Hi93iWK85kxzzX+kN3jdqb00Pm61Zcjh4dSEUWoX4u/V8ErhIx/Zu76yp8H4MnH RPLrEWJhcmhpA0fW07UQdyQPACcUW7LS3LjZ1yUXrCUTDh+L8erjx8KBI1TdMict6c2GQXJewlEIvP+xIUBYBw== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Nicolas Pitre Reviewed-by: Greg Ungerer --- fs/binfmt_flat.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index 34f815540e..28fc272d9a 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -383,36 +383,39 @@ static void old_reloc(unsigned long rl) { static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; 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); pr_debug("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]); 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: pr_err("Unknown relocation type=%x\n", r.reloc.type); break; } + __put_user(val, ptr); - pr_debug("Relocation became %lx\n", *ptr); -} + pr_debug("Relocation became %lx\n", val); +} /****************************************************************************/ @@ -783,8 +786,13 @@ 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); -- 2.7.4