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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 53555C43603 for ; Tue, 10 Dec 2019 21:08:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 217D524697 for ; Tue, 10 Dec 2019 21:08:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576012085; bh=MlG9exxlQ96joQ8jTOQ8joUO6pD4ZycdLLJfsJLHePs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=NLYRPwreqOUfFP7q0MNhxtdppj76E4MqXaKDQD8wTuUmdeRLSBggpAmYWjj9Ol2x/ mvNg6AgqEmbCCm9WW13VlzgzLPundvt0zKbIzodn/oQJPUyGHtYbU2ff7Py6o923cw r4mdCTjXIJDtQMJCfQ3ejcjnA6cbFY6YPDebk2dk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727771AbfLJVIE (ORCPT ); Tue, 10 Dec 2019 16:08:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:54654 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727542AbfLJVHz (ORCPT ); Tue, 10 Dec 2019 16:07:55 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8E53920836; Tue, 10 Dec 2019 21:07:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576012074; bh=MlG9exxlQ96joQ8jTOQ8joUO6pD4ZycdLLJfsJLHePs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GmvlZrSfyxaGh5SuMSwE2OLUEwCu/2taQJQXTnsCQv9pHVXaTjEdV96/7ruM/k3NQ Wlh8lMPB8sxKA21u9EbUd2TK1KeS2+3Pc7zV6+IW+Xp8+veot3Dmmn9Li8UkNmgICy +kYRo+CI9j5Q1gmIlTv3oS4LUVrOzpZyMkEcqAXk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Arnd Bergmann , Borislav Petkov , Kees Cook , "H. Peter Anvin" , Bill Metzenthen , Ingo Molnar , Thomas Gleixner , x86-ml , Sasha Levin Subject: [PATCH AUTOSEL 5.4 054/350] x86/math-emu: Check __copy_from_user() result Date: Tue, 10 Dec 2019 16:02:39 -0500 Message-Id: <20191210210735.9077-15-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191210210735.9077-1-sashal@kernel.org> References: <20191210210735.9077-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann [ Upstream commit e6b44ce1925a8329a937c57f0d60ba0d9bb5d226 ] The new __must_check annotation on __copy_from_user() successfully identified some code that has lacked the check since at least linux-2.1.73: arch/x86/math-emu/reg_ld_str.c:88:2: error: ignoring return value of \ function declared with 'warn_unused_result' attribute [-Werror,-Wunused-result]         __copy_from_user(sti_ptr, s, 10);         ^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~ arch/x86/math-emu/reg_ld_str.c:1129:2: error: ignoring return value of \ function declared with 'warn_unused_result' attribute [-Werror,-Wunused-result]         __copy_from_user(register_base + offset, s, other);         ^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/x86/math-emu/reg_ld_str.c:1131:3: error: ignoring return value of \ function declared with 'warn_unused_result' attribute [-Werror,-Wunused-result]                 __copy_from_user(register_base, s + other, offset);                 ^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In addition, the get_user()/put_user() helpers do not enforce a return value check, but actually still require one. These have been missing for even longer. Change the internal wrappers around get_user()/put_user() to force a signal and add a corresponding wrapper around __copy_from_user() to check all such cases. [ bp: Break long lines. ] Fixes: 257e458057e5 ("Import 2.1.73") Fixes: 9dd819a15162 ("uaccess: add missing __must_check attributes") Signed-off-by: Arnd Bergmann Signed-off-by: Borislav Petkov Reviewed-by: Kees Cook Cc: "H. Peter Anvin" Cc: Bill Metzenthen Cc: Ingo Molnar Cc: Thomas Gleixner Cc: x86-ml Link: https://lkml.kernel.org/r/20191001142344.1274185-1-arnd@arndb.de Signed-off-by: Sasha Levin --- arch/x86/math-emu/fpu_system.h | 6 ++++-- arch/x86/math-emu/reg_ld_str.c | 6 +++--- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/arch/x86/math-emu/fpu_system.h b/arch/x86/math-emu/fpu_system.h index f98a0c9567646..9b41391867dca 100644 --- a/arch/x86/math-emu/fpu_system.h +++ b/arch/x86/math-emu/fpu_system.h @@ -107,6 +107,8 @@ static inline bool seg_writable(struct desc_struct *d) #define FPU_access_ok(y,z) if ( !access_ok(y,z) ) \ math_abort(FPU_info,SIGSEGV) #define FPU_abort math_abort(FPU_info, SIGSEGV) +#define FPU_copy_from_user(to, from, n) \ + do { if (copy_from_user(to, from, n)) FPU_abort; } while (0) #undef FPU_IGNORE_CODE_SEGV #ifdef FPU_IGNORE_CODE_SEGV @@ -122,7 +124,7 @@ static inline bool seg_writable(struct desc_struct *d) #define FPU_code_access_ok(z) FPU_access_ok((void __user *)FPU_EIP,z) #endif -#define FPU_get_user(x,y) get_user((x),(y)) -#define FPU_put_user(x,y) put_user((x),(y)) +#define FPU_get_user(x,y) do { if (get_user((x),(y))) FPU_abort; } while (0) +#define FPU_put_user(x,y) do { if (put_user((x),(y))) FPU_abort; } while (0) #endif diff --git a/arch/x86/math-emu/reg_ld_str.c b/arch/x86/math-emu/reg_ld_str.c index f3779743d15e6..fe6246ff98870 100644 --- a/arch/x86/math-emu/reg_ld_str.c +++ b/arch/x86/math-emu/reg_ld_str.c @@ -85,7 +85,7 @@ int FPU_load_extended(long double __user *s, int stnr) RE_ENTRANT_CHECK_OFF; FPU_access_ok(s, 10); - __copy_from_user(sti_ptr, s, 10); + FPU_copy_from_user(sti_ptr, s, 10); RE_ENTRANT_CHECK_ON; return FPU_tagof(sti_ptr); @@ -1126,9 +1126,9 @@ void frstor(fpu_addr_modes addr_modes, u_char __user *data_address) /* Copy all registers in stack order. */ RE_ENTRANT_CHECK_OFF; FPU_access_ok(s, 80); - __copy_from_user(register_base + offset, s, other); + FPU_copy_from_user(register_base + offset, s, other); if (offset) - __copy_from_user(register_base, s + other, offset); + FPU_copy_from_user(register_base, s + other, offset); RE_ENTRANT_CHECK_ON; for (i = 0; i < 8; i++) { -- 2.20.1