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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 85CFBC32750 for ; Tue, 13 Aug 2019 21:04:16 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4E73120840 for ; Tue, 13 Aug 2019 21:04:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4E73120840 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6C1256B000A; Tue, 13 Aug 2019 17:03:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6770A6B02AA; Tue, 13 Aug 2019 17:03:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3B48B6B02AB; Tue, 13 Aug 2019 17:03:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 0D93A6B000A for ; Tue, 13 Aug 2019 17:03:46 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id A3FD48248AA2 for ; Tue, 13 Aug 2019 21:03:45 +0000 (UTC) X-FDA: 75818631210.07.ship94_209cfd6a0c93c X-HE-Tag: ship94_209cfd6a0c93c X-Filterd-Recvd-Size: 4223 Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Tue, 13 Aug 2019 21:03:43 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Aug 2019 14:03:42 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,382,1559545200"; d="scan'208";a="194275998" Received: from yyu32-desk1.sc.intel.com ([10.144.153.205]) by fmsmga001.fm.intel.com with ESMTP; 13 Aug 2019 14:03:41 -0700 From: Yu-cheng Yu To: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin Cc: Yu-cheng Yu Subject: [PATCH v8 11/14] x86/vsyscall/64: Fixup shadow stack and branch tracking for vsyscall Date: Tue, 13 Aug 2019 13:53:56 -0700 Message-Id: <20190813205359.12196-12-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190813205359.12196-1-yu-cheng.yu@intel.com> References: <20190813205359.12196-1-yu-cheng.yu@intel.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: When emulating a RET, also unwind the task's shadow stack and cancel the current branch tracking status. Signed-off-by: Yu-cheng Yu --- arch/x86/entry/vsyscall/vsyscall_64.c | 29 ++++++++++++++++++++++++ arch/x86/entry/vsyscall/vsyscall_trace.h | 1 + 2 files changed, 30 insertions(+) diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index e7c596dea947..27ff81f75c82 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -38,6 +38,9 @@ #include #include #include +#include +#include +#include #define CREATE_TRACE_POINTS #include "vsyscall_trace.h" @@ -286,6 +289,32 @@ bool emulate_vsyscall(unsigned long error_code, /* Emulate a ret instruction. */ regs->ip = caller; regs->sp += 8; + + /* Unwind shadow stack. */ + +#ifdef CONFIG_X86_INTEL_SHADOW_STACK_USER + if (current->thread.cet.shstk_enabled) { + u64 r; + + modify_fpu_regs_begin(); + rdmsrl(MSR_IA32_PL3_SSP, r); + wrmsrl(MSR_IA32_PL3_SSP, r + 8); + modify_fpu_regs_end(); + } +#endif + + /* Fixup branch tracking */ +#ifdef CONFIG_X86_INTEL_BRANCH_TRACKING_USER + if (current->thread.cet.ibt_enabled) { + u64 r; + + modify_fpu_regs_begin(); + rdmsrl(MSR_IA32_U_CET, r); + wrmsrl(MSR_IA32_U_CET, r & ~MSR_IA32_CET_WAIT_ENDBR); + modify_fpu_regs_end(); + } +#endif + return true; sigsegv: diff --git a/arch/x86/entry/vsyscall/vsyscall_trace.h b/arch/x86/entry/vsyscall/vsyscall_trace.h index 3c3f9765a85c..7aa2101ada44 100644 --- a/arch/x86/entry/vsyscall/vsyscall_trace.h +++ b/arch/x86/entry/vsyscall/vsyscall_trace.h @@ -25,6 +25,7 @@ TRACE_EVENT(emulate_vsyscall, #endif #undef TRACE_INCLUDE_PATH +#undef TRACE_INCLUDE_FILE #define TRACE_INCLUDE_PATH ../../arch/x86/entry/vsyscall/ #define TRACE_INCLUDE_FILE vsyscall_trace #include -- 2.17.1