Bugzilla: 1102715 Upstream-status: Submitted for 3.15 and CC'd to stable Delivered-To: jwboyer@gmail.com Received: by 10.76.6.212 with SMTP id d20csp285523oaa; Wed, 28 May 2014 20:10:58 -0700 (PDT) X-Received: by 10.66.250.166 with SMTP id zd6mr4872927pac.7.1401333057574; Wed, 28 May 2014 20:10:57 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id j1si26042371pbw.214.2014.05.28.20.10.31 for ; Wed, 28 May 2014 20:10:57 -0700 (PDT) Received-SPF: none (google.com: stable-owner@vger.kernel.org does not designate permitted sender hosts) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=neutral (google.com: stable-owner@vger.kernel.org does not designate permitted sender hosts) smtp.mail=stable-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755059AbaE2DKa (ORCPT + 73 others); Wed, 28 May 2014 23:10:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34907 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753861AbaE2DK3 (ORCPT ); Wed, 28 May 2014 23:10:29 -0400 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s4T3AQfK017267 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 28 May 2014 23:10:26 -0400 Received: from paris.rdu.redhat.com (paris.rdu.redhat.com [10.13.136.28]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s4T3APd7019240; Wed, 28 May 2014 23:10:26 -0400 From: Eric Paris To: torvalds@linux-foundation.org Cc: linux-audit@redhat.com, linux-kernel@vger.kernel.org, Andy Lutomirski , stable@vger.kernel.org, Eric Paris Subject: [PATCH 1/2] auditsc: audit_krule mask accesses need bounds checking Date: Wed, 28 May 2014 23:09:58 -0400 Message-Id: <1401332999-15167-1-git-send-email-eparis@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Andy Lutomirski Fixes an easy DoS and possible information disclosure. This does nothing about the broken state of x32 auditing. eparis: If the admin has enabled auditd and has specifically loaded audit rules. This bug has been around since before git. Wow... Cc: stable@vger.kernel.org Signed-off-by: Andy Lutomirski Signed-off-by: Eric Paris --- kernel/auditsc.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 254ce20..842f58a 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -728,6 +728,22 @@ static enum audit_state audit_filter_task(struct task_struct *tsk, char **key) return AUDIT_BUILD_CONTEXT; } +static int audit_in_mask(const struct audit_krule *rule, unsigned long val) +{ + int word, bit; + + if (val > 0xffffffff) + return false; + + word = AUDIT_WORD(val); + if (word >= AUDIT_BITMASK_SIZE) + return false; + + bit = AUDIT_BIT(val); + + return rule->mask[word] & bit; +} + /* At syscall entry and exit time, this filter is called if the * audit_state is not low enough that auditing cannot take place, but is * also not high enough that we already know we have to write an audit @@ -745,11 +761,8 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk, rcu_read_lock(); if (!list_empty(list)) { - int word = AUDIT_WORD(ctx->major); - int bit = AUDIT_BIT(ctx->major); - list_for_each_entry_rcu(e, list, list) { - if ((e->rule.mask[word] & bit) == bit && + if (audit_in_mask(&e->rule, ctx->major) && audit_filter_rules(tsk, &e->rule, ctx, NULL, &state, false)) { rcu_read_unlock(); @@ -769,20 +782,16 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk, static int audit_filter_inode_name(struct task_struct *tsk, struct audit_names *n, struct audit_context *ctx) { - int word, bit; int h = audit_hash_ino((u32)n->ino); struct list_head *list = &audit_inode_hash[h]; struct audit_entry *e; enum audit_state state; - word = AUDIT_WORD(ctx->major); - bit = AUDIT_BIT(ctx->major); - if (list_empty(list)) return 0; list_for_each_entry_rcu(e, list, list) { - if ((e->rule.mask[word] & bit) == bit && + if (audit_in_mask(&e->rule, ctx->major) && audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) { ctx->current_state = state; return 1; -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html