From patchwork Tue Nov 24 10:19:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Borislav Petkov X-Patchwork-Id: 1344557 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F17D1C64E7A 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 96DC720708 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="CAT2DMPj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731898AbgKXKUN (ORCPT ); Tue, 24 Nov 2020 05:20:13 -0500 Received: from mail.skyhub.de ([5.9.137.197]:50314 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731861AbgKXKUG (ORCPT ); Tue, 24 Nov 2020 05:20:06 -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 2A28D1EC0258; Tue, 24 Nov 2020 11:20:05 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1606213205; 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=HZOMF0xnv/asL+0NdEME9qH39KkBlzno1GuCd8ZruUg=; b=CAT2DMPjOIsYz2sqSqiaLAr/dmHpGZENawj1lawO87n6oMUCUBlHqBRrJvAsdHDAlfwmCQ ZWQxyEoNqDTyzCGrPAYzmMdZvTMvwmRg10OSK4IcbeNBNp0KcAgbGLXdjw0fVdwT/CL6lr adozS0LiPh4uOdcQqmdl4gS3kDGJYQI= From: Borislav Petkov To: Andy Lutomirski , Masami Hiramatsu Cc: X86 ML , LKML Subject: [RFC PATCH v0 07/19] perf/x86/intel/ds: Check return values of insn decoder functions Date: Tue, 24 Nov 2020 11:19:40 +0100 Message-Id: <20201124101952.7909-8-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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov branch_type() doesn't need to call the full insn_decode() because it doesn't need it in all cases thus leave the calls separate. Signed-off-by: Borislav Petkov --- arch/x86/events/intel/lbr.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index 1aadb253d296..0b7d2cc3f001 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -1224,8 +1224,7 @@ static int branch_type(unsigned long from, unsigned long to, int abort) is64 = kernel_ip((unsigned long)addr) || any_64bit_mode(current_pt_regs()); #endif insn_init(&insn, addr, bytes_read, is64); - insn_get_opcode(&insn); - if (!insn.opcode.got) + if (insn_get_opcode(&insn)) return X86_BR_ABORT; switch (insn.opcode.bytes[0]) { @@ -1262,8 +1261,7 @@ static int branch_type(unsigned long from, unsigned long to, int abort) ret = X86_BR_INT; break; case 0xe8: /* call near rel */ - insn_get_immediate(&insn); - if (insn.immediate1.value == 0) { + if (insn_get_immediate(&insn) || insn.immediate1.value == 0) { /* zero length call */ ret = X86_BR_ZERO_CALL; break; @@ -1279,7 +1277,9 @@ static int branch_type(unsigned long from, unsigned long to, int abort) ret = X86_BR_JMP; break; case 0xff: /* call near absolute, call far absolute ind */ - insn_get_modrm(&insn); + if (insn_get_modrm(&insn)) + return X86_BR_ABORT; + ext = (insn.modrm.bytes[0] >> 3) & 0x7; switch (ext) { case 2: /* near ind call */