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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, 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 7CFF2C6379D for ; Tue, 24 Nov 2020 10:20:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 18E1120708 for ; Tue, 24 Nov 2020 10:20:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="nXW62cHa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731862AbgKXKUF (ORCPT ); Tue, 24 Nov 2020 05:20:05 -0500 Received: from mail.skyhub.de ([5.9.137.197]:50324 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731846AbgKXKUE (ORCPT ); Tue, 24 Nov 2020 05:20:04 -0500 Received: from zn.tnic (p200300ec2f0e360052021be21853ebf1.dip0.t-ipconnect.de [IPv6:2003:ec:2f0e:3600:5202:1be2:1853:ebf1]) (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 15ECA1EC0537; Tue, 24 Nov 2020 11:20:03 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1606213203; 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:in-reply-to:references:references; bh=4CjMZvNFahVZWG+t3f+MDdber+Z+j4pDcsKb1HZOXlw=; b=nXW62cHayHGTvJ5xjpFsMkZtvlK1Blb2iSW6fo5okIdJLWz5fPR8rVsYa4qO6tPWyBvBbj KLjhcM2h/xjTrfJ1Uz1ePz21OaT1CgKtlwCslssm+bp2b1wsUDnJYzCq3CVrpB0mk0vmcc PFUJFa70M47a5LVp3NUH1PT9vhbLZ50= From: Borislav Petkov To: Andy Lutomirski , Masami Hiramatsu Cc: X86 ML , LKML Subject: [RFC PATCH v0 04/19] x86/insn-eval: Handle return values from the decoder Date: Tue, 24 Nov 2020 11:19:37 +0100 Message-Id: <20201124101952.7909-5-bp@alien8.de> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20201124101952.7909-1-bp@alien8.de> References: <20201124101952.7909-1-bp@alien8.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov Now that the different instruction inspecting functions return a value, test that and return early from callers if error has been encountered. Signed-off-by: Borislav Petkov --- arch/x86/lib/insn-eval.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index 99fafbaf8555..5825b4cf4386 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -1117,7 +1117,8 @@ static int get_eff_addr_sib(struct insn *insn, struct pt_regs *regs, if (insn->addr_bytes != 8 && insn->addr_bytes != 4) return -EINVAL; - insn_get_modrm(insn); + if (insn_get_modrm(insn)) + return -EINVAL; if (!insn->modrm.nbytes) return -EINVAL; @@ -1125,7 +1126,8 @@ static int get_eff_addr_sib(struct insn *insn, struct pt_regs *regs, if (X86_MODRM_MOD(insn->modrm.value) > 2) return -EINVAL; - insn_get_sib(insn); + if (insn_get_sib(insn)) + return -EINVAL; if (!insn->sib.nbytes) return -EINVAL; @@ -1194,8 +1196,8 @@ static void __user *get_addr_ref_16(struct insn *insn, struct pt_regs *regs) short eff_addr; long tmp; - insn_get_modrm(insn); - insn_get_displacement(insn); + if (insn_get_modrm(insn) || insn_get_displacement(insn)) + goto out; if (insn->addr_bytes != 2) goto out; @@ -1491,7 +1493,9 @@ bool insn_decode_regs(struct insn *insn, struct pt_regs *regs, insn->addr_bytes = INSN_CODE_SEG_ADDR_SZ(seg_defs); insn->opnd_bytes = INSN_CODE_SEG_OPND_SZ(seg_defs); - insn_get_length(insn); + if (insn_get_length(insn)) + return false; + if (buf_size < insn->length) return false; -- 2.21.0