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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC141C4332F for ; Mon, 6 Dec 2021 15:33:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349518AbhLFPgZ (ORCPT ); Mon, 6 Dec 2021 10:36:25 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:48546 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1388440AbhLFPcq (ORCPT ); Mon, 6 Dec 2021 10:32:46 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8006561310; Mon, 6 Dec 2021 15:29:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 676D8C34900; Mon, 6 Dec 2021 15:29:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1638804557; bh=DKTPlAHGNp7hl5YY5FYZAl7aOhAQaXfXsmdHoIjod/A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gEBvppDhpq1FX4lOrwsIQLOLWZ3M+6Yx8VLIRm2HWwICcBiiBUSXkjNFwYVHEtXv9 A7J0B8T6QlwLT4jcdgCLtInI1zkhOfkVO5LpAxDIeUOIYi1CddeyNStja2QBwnpr1y GUcDp62Hg2jCltFHdUMtTP27Pd/W+6mTIhoYFzmo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Sterritt , Borislav Petkov , Paolo Bonzini , Marc Orr , Peter Gonda , Joerg Roedel , Sasha Levin Subject: [PATCH 5.15 172/207] x86/sev: Fix SEV-ES INS/OUTS instructions for word, dword, and qword Date: Mon, 6 Dec 2021 15:57:06 +0100 Message-Id: <20211206145616.220150126@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211206145610.172203682@linuxfoundation.org> References: <20211206145610.172203682@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Michael Sterritt [ Upstream commit 1d5379d0475419085d3575bd9155f2e558e96390 ] Properly type the operands being passed to __put_user()/__get_user(). Otherwise, these routines truncate data for dependent instructions (e.g., INSW) and only read/write one byte. This has been tested by sending a string with REP OUTSW to a port and then reading it back in with REP INSW on the same port. Previous behavior was to only send and receive the first char of the size. For example, word operations for "abcd" would only read/write "ac". With change, the full string is now written and read back. Fixes: f980f9c31a923 (x86/sev-es: Compile early handler code into kernel image) Signed-off-by: Michael Sterritt Signed-off-by: Borislav Petkov Reviewed-by: Paolo Bonzini Reviewed-by: Marc Orr Reviewed-by: Peter Gonda Reviewed-by: Joerg Roedel Link: https://lkml.kernel.org/r/20211119232757.176201-1-sterritt@google.com Signed-off-by: Sasha Levin --- arch/x86/kernel/sev.c | 57 +++++++++++++++++++++++++++++-------------- 1 file changed, 39 insertions(+), 18 deletions(-) diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index 88401675dabb0..a0064cf77e562 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -294,11 +294,6 @@ static enum es_result vc_write_mem(struct es_em_ctxt *ctxt, char *dst, char *buf, size_t size) { unsigned long error_code = X86_PF_PROT | X86_PF_WRITE; - char __user *target = (char __user *)dst; - u64 d8; - u32 d4; - u16 d2; - u8 d1; /* * This function uses __put_user() independent of whether kernel or user @@ -320,26 +315,42 @@ static enum es_result vc_write_mem(struct es_em_ctxt *ctxt, * instructions here would cause infinite nesting. */ switch (size) { - case 1: + case 1: { + u8 d1; + u8 __user *target = (u8 __user *)dst; + memcpy(&d1, buf, 1); if (__put_user(d1, target)) goto fault; break; - case 2: + } + case 2: { + u16 d2; + u16 __user *target = (u16 __user *)dst; + memcpy(&d2, buf, 2); if (__put_user(d2, target)) goto fault; break; - case 4: + } + case 4: { + u32 d4; + u32 __user *target = (u32 __user *)dst; + memcpy(&d4, buf, 4); if (__put_user(d4, target)) goto fault; break; - case 8: + } + case 8: { + u64 d8; + u64 __user *target = (u64 __user *)dst; + memcpy(&d8, buf, 8); if (__put_user(d8, target)) goto fault; break; + } default: WARN_ONCE(1, "%s: Invalid size: %zu\n", __func__, size); return ES_UNSUPPORTED; @@ -362,11 +373,6 @@ static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, char *src, char *buf, size_t size) { unsigned long error_code = X86_PF_PROT; - char __user *s = (char __user *)src; - u64 d8; - u32 d4; - u16 d2; - u8 d1; /* * This function uses __get_user() independent of whether kernel or user @@ -388,26 +394,41 @@ static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, * instructions here would cause infinite nesting. */ switch (size) { - case 1: + case 1: { + u8 d1; + u8 __user *s = (u8 __user *)src; + if (__get_user(d1, s)) goto fault; memcpy(buf, &d1, 1); break; - case 2: + } + case 2: { + u16 d2; + u16 __user *s = (u16 __user *)src; + if (__get_user(d2, s)) goto fault; memcpy(buf, &d2, 2); break; - case 4: + } + case 4: { + u32 d4; + u32 __user *s = (u32 __user *)src; + if (__get_user(d4, s)) goto fault; memcpy(buf, &d4, 4); break; - case 8: + } + case 8: { + u64 d8; + u64 __user *s = (u64 __user *)src; if (__get_user(d8, s)) goto fault; memcpy(buf, &d8, 8); break; + } default: WARN_ONCE(1, "%s: Invalid size: %zu\n", __func__, size); return ES_UNSUPPORTED; -- 2.33.0