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=-13.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,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 87DEEC433DB for ; Wed, 24 Feb 2021 11:05:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 34B8564ECF for ; Wed, 24 Feb 2021 11:05:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234903AbhBXLE3 (ORCPT ); Wed, 24 Feb 2021 06:04:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234958AbhBXLDR (ORCPT ); Wed, 24 Feb 2021 06:03:17 -0500 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FA77C061574 for ; Wed, 24 Feb 2021 03:02:37 -0800 (PST) Received: from zn.tnic (p200300ec2f0d180081510bd8ee909965.dip0.t-ipconnect.de [IPv6:2003:ec:2f0d:1800:8151:bd8:ee90:9965]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id DC9E21EC059D; Wed, 24 Feb 2021 12:02:35 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1614164556; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type: content-transfer-encoding:content-transfer-encoding:in-reply-to: references; bh=xdguPOV6gl09LcJ8hAgh1QamXpmENMoCtaX8467xqDQ=; b=AvIzn959krERkupjy2GAzIUO4qOB+UpzRhilZHkfc/S6p/4RKIiz2u/OkHxxtPNNb7D6/J ZACMLj+8hHYSsh0IgEJcF6rn9JGjowcjm7MjOHeZtg42Ts8Zx9u3FJuGI/+WTD8w7nXp4V vGd9mfZFLKodQUjk2O4hpb9JXb0VUT8= From: Borislav Petkov To: X86 ML Cc: Masami Hiramatsu , LKML Subject: [PATCH v2 00/21] x86/insn: Add an insn_decode() API Date: Wed, 24 Feb 2021 12:02:12 +0100 Message-Id: <20210224110233.19715-1-bp@alien8.de> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov Hi all, finally had some time during the merge window to finish reworking this. Most if not all review feedback should be incorporated. Thx. Changelog: ========== v1: --- here's v1 with the requested change to return -ENODATA on short input to the decoder. The rest is as in the previous submission. Only lightly tested. Thx. v0: --- https://lkml.kernel.org/r/20201124101952.7909-1-bp@alien8.de here's what I had in mind, finally split into proper patches. The final goal is for all users of the decoder to simply call insn_decode() and look at its retval. Simple. As to amluto's question about detecting partial insns, see the diff below. Running that gives: insn buffer: 0x48 0xcf 0x48 0x83 0x90 0x90 0x90 0x90 0x90 0x90 0x90 0x90 0x90 0x90 0x90 supplied buf size: 15, ret 0 supplied buf size: 2, ret 0 supplied buf size: 3, ret 0 supplied buf size: 4, ret 0 and the return value is always success. Which means that that buf_len that gets supplied to the decoder functions doesn't really work and I need to look into it. That is, provided this is how we want to control what the instruction decoder decodes - by supplying the length of the buffer it should look at. We could also say that probably there should be a way to say "decode only the first insn in the buffer and ignore the rest". That is all up to the use cases so I'm looking for suggestions here. In any case, at least the case where I give it 0x48 0xcf 0x48 0x83 and say that buf size is 4, should return an error because the second insn is incomplete. So I need to go look at that now. Borislav Petkov (21): x86/insn: Rename insn_decode() to insn_decode_from_regs() x86/insn: Add @buf_len param to insn_init() kernel-doc comment x86/insn: Add a __ignore_sync_check__ marker x86/insn: Add an insn_decode() API x86/insn-eval: Handle return values from the decoder x86/boot/compressed/sev-es: Convert to insn_decode() perf/x86/intel/ds: Check insn_get_length() retval perf/x86/intel/ds: Check return values of insn decoder functions x86/alternative: Use insn_decode() x86/mce: Convert to insn_decode() x86/kprobes: Convert to insn_decode() x86/sev-es: Split vc_decode_insn() x86/sev-es: Convert to insn_decode() x86/traps: Convert to insn_decode() x86/uprobes: Convert to insn_decode() x86/tools/insn_decoder_test: Convert to insn_decode() tools/objtool: Convert to insn_decode() x86/tools/insn_sanity: Convert to insn_decode() tools/perf: Convert to insn_decode() x86/insn: Remove kernel_insn_init() x86/insn: Make insn_complete() static arch/x86/boot/compressed/sev-es.c | 11 +- arch/x86/events/intel/ds.c | 11 +- arch/x86/events/intel/lbr.c | 10 +- arch/x86/include/asm/inat.h | 2 +- arch/x86/include/asm/insn-eval.h | 4 +- arch/x86/include/asm/insn.h | 44 ++- arch/x86/kernel/alternative.c | 6 +- arch/x86/kernel/cpu/mce/severity.c | 12 +- arch/x86/kernel/kprobes/core.c | 17 +- arch/x86/kernel/kprobes/opt.c | 9 +- arch/x86/kernel/sev-es.c | 63 +++-- arch/x86/kernel/traps.c | 7 +- arch/x86/kernel/umip.c | 2 +- arch/x86/kernel/uprobes.c | 8 +- arch/x86/lib/inat.c | 2 +- arch/x86/lib/insn-eval.c | 40 +-- arch/x86/lib/insn.c | 255 ++++++++++++++---- arch/x86/tools/insn_decoder_test.c | 10 +- arch/x86/tools/insn_sanity.c | 8 +- tools/arch/x86/include/asm/inat.h | 2 +- tools/arch/x86/include/asm/insn.h | 44 ++- tools/arch/x86/lib/inat.c | 2 +- tools/arch/x86/lib/insn.c | 255 ++++++++++++++---- tools/include/linux/kconfig.h | 73 +++++ tools/objtool/arch/x86/decode.c | 9 +- tools/objtool/sync-check.sh | 17 +- tools/perf/arch/x86/tests/insn-x86.c | 9 +- tools/perf/arch/x86/util/archinsn.c | 9 +- tools/perf/check-headers.sh | 15 +- .../intel-pt-decoder/intel-pt-insn-decoder.c | 17 +- 30 files changed, 678 insertions(+), 295 deletions(-) create mode 100644 tools/include/linux/kconfig.h -- 2.29.2