From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9B43CC2D0CE for ; Fri, 24 Jan 2020 09:38:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6AF47208C4 for ; Fri, 24 Jan 2020 09:38:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579858707; bh=QDKSUapnYTJV9YDZiQ2dSpHwPO9fJ6OQJzfqRcimlso=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=aHSfek4rR0s65r8LNZypGDR1VIlxiBteG7ZYTjR4GdQN+rYLr6aPid7AyqFyRZ774 r9aokot71stN2kxV/P0AqqfdCD2V6rmpiT8iZkLSsIeo2KBJhaTg7AQx/wgbqT5x7z Ito+IRudeQtzVV1OzufAcgEk99dYaBywqak/eYAw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730321AbgAXJi0 (ORCPT ); Fri, 24 Jan 2020 04:38:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:35544 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725821AbgAXJiZ (ORCPT ); Fri, 24 Jan 2020 04:38:25 -0500 Received: from localhost (unknown [145.15.244.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A4EC120709; Fri, 24 Jan 2020 09:38:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579858704; bh=QDKSUapnYTJV9YDZiQ2dSpHwPO9fJ6OQJzfqRcimlso=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=InsFftzaufCSfOTfyU5QaUkEMzqgCsHjAtL0IsCPEkIfyS/Tz4fXlapXqLI2HbqUA 9D3bDNhRzUl2eFdzPsRrZWAyq6Q1XHfKMp5qNyNv3EjxEvIndVV/eauI1vkda5WW5u SDxhyZD5t7OEmnfo5WvFS+qtESKEESTLkyto63sE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Geert Uytterhoeven , Michael Ellerman Subject: [PATCH 5.4 019/102] powerpc/security: Fix debugfs data leak on 32-bit Date: Fri, 24 Jan 2020 10:30:20 +0100 Message-Id: <20200124092809.069364174@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124092806.004582306@linuxfoundation.org> References: <20200124092806.004582306@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Geert Uytterhoeven commit 3b05a1e517e1a8cfda4866ec31d28b2bc4fee4c4 upstream. "powerpc_security_features" is "unsigned long", i.e. 32-bit or 64-bit, depending on the platform (PPC_FSL_BOOK3E or PPC_BOOK3S_64). Hence casting its address to "u64 *", and calling debugfs_create_x64() is wrong, and leaks 32-bit of nearby data to userspace on 32-bit platforms. While all currently defined SEC_FTR_* security feature flags fit in 32-bit, they all have "ULL" suffixes to make them 64-bit constants. Hence fix the leak by changing the type of "powerpc_security_features" (and the parameter types of its accessors) to "u64". This also allows to drop the cast. Fixes: 398af571128fe75f ("powerpc/security: Show powerpc_security_features in debugfs") Signed-off-by: Geert Uytterhoeven Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191021142309.28105-1-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/include/asm/security_features.h | 8 ++++---- arch/powerpc/kernel/security.c | 4 ++-- 2 files changed, 6 insertions(+), 6 deletions(-) --- a/arch/powerpc/include/asm/security_features.h +++ b/arch/powerpc/include/asm/security_features.h @@ -9,7 +9,7 @@ #define _ASM_POWERPC_SECURITY_FEATURES_H -extern unsigned long powerpc_security_features; +extern u64 powerpc_security_features; extern bool rfi_flush; /* These are bit flags */ @@ -24,17 +24,17 @@ void setup_stf_barrier(void); void do_stf_barrier_fixups(enum stf_barrier_type types); void setup_count_cache_flush(void); -static inline void security_ftr_set(unsigned long feature) +static inline void security_ftr_set(u64 feature) { powerpc_security_features |= feature; } -static inline void security_ftr_clear(unsigned long feature) +static inline void security_ftr_clear(u64 feature) { powerpc_security_features &= ~feature; } -static inline bool security_ftr_enabled(unsigned long feature) +static inline bool security_ftr_enabled(u64 feature) { return !!(powerpc_security_features & feature); } --- a/arch/powerpc/kernel/security.c +++ b/arch/powerpc/kernel/security.c @@ -16,7 +16,7 @@ #include -unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT; +u64 powerpc_security_features __read_mostly = SEC_FTR_DEFAULT; enum count_cache_flush_type { COUNT_CACHE_FLUSH_NONE = 0x1, @@ -109,7 +109,7 @@ device_initcall(barrier_nospec_debugfs_i static __init int security_feature_debugfs_init(void) { debugfs_create_x64("security_features", 0400, powerpc_debugfs_root, - (u64 *)&powerpc_security_features); + &powerpc_security_features); return 0; } device_initcall(security_feature_debugfs_init);