From nobody Thu May 15 10:38:47 2025 Delivered-To: importer2@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer2=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1699539350156316.9232073757249; Thu, 9 Nov 2023 06:15:50 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r15fv-0006Lx-Fl; Thu, 09 Nov 2023 09:06:27 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r15dj-0000Wa-Ap; Thu, 09 Nov 2023 09:04:14 -0500 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r15de-00078w-Qx; Thu, 09 Nov 2023 09:04:10 -0500 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id D68EF31BE8; Thu, 9 Nov 2023 16:59:57 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id DFB383451F; Thu, 9 Nov 2023 16:59:49 +0300 (MSK) Received: (nullmailer pid 1462924 invoked by uid 1000); Thu, 09 Nov 2023 13:59:47 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Peter Maydell , Richard Henderson , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Michael Tokarev Subject: [Stable-7.2.7 48/62] target/arm: Don't allow stage 2 page table walks to downgrade to NS Date: Thu, 9 Nov 2023 16:59:16 +0300 Message-Id: <20231109135933.1462615-48-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer2=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer2=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer2=patchew.org@nongnu.org X-ZM-MESSAGEID: 1699539351690100003 From: Peter Maydell Bit 63 in a Table descriptor is only the NSTable bit for stage 1 translations; in stage 2 it is RES0. We were incorrectly looking at it all the time. This causes problems if: * the stage 2 table descriptor was incorrectly setting the RES0 bit * we are doing a stage 2 translation in Secure address space for a NonSecure stage 1 regime -- in this case we would incorrectly do an immediate downgrade to NonSecure A bug elsewhere in the code currently prevents us from getting to the second situation, but when we fix that it will be possible. Cc: qemu-stable@nongnu.org Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daud=C3=A9 Message-id: 20230504135425.2748672-2-peter.maydell@linaro.org (cherry picked from commit 21a4ab8318ba6f049aac244e237cd1557586e216) Signed-off-by: Michael Tokarev diff --git a/target/arm/ptw.c b/target/arm/ptw.c index fa013044c1..e593bc339a 100644 --- a/target/arm/ptw.c +++ b/target/arm/ptw.c @@ -1382,17 +1382,18 @@ static bool get_phys_addr_lpae(CPUARMState *env, S1= Translate *ptw, descaddrmask &=3D ~indexmask_grainsize; =20 /* - * Secure accesses start with the page table in secure memory and + * Secure stage 1 accesses start with the page table in secure memory = and * can be downgraded to non-secure at any step. Non-secure accesses * remain non-secure. We implement this by just ORing in the NSTable/NS * bits at each step. + * Stage 2 never gets this kind of downgrade. */ tableattrs =3D is_secure ? 0 : (1 << 4); =20 next_level: descaddr |=3D (address >> (stride * (4 - level))) & indexmask; descaddr &=3D ~7ULL; - nstable =3D extract32(tableattrs, 4, 1); + nstable =3D !regime_is_stage2(mmu_idx) && extract32(tableattrs, 4, 1); if (nstable) { /* * Stage2_S -> Stage2 or Phys_S -> Phys_NS --=20 2.39.2