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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 B13D8C2D0CE for ; Sun, 29 Dec 2019 18:14:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 877AB207E0 for ; Sun, 29 Dec 2019 18:14:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577643256; bh=CFq7QeTcEXfVevTxoQrg/wPsOlCDpo63+EilV2uVLvA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fx79T2bYone/VBb3hFoCt5yYAG2BWBi5fClHCU3P4v5wWg/TRN6qjOoGIh9uONhop DyAZPT0J+ysIAVDV659nOiymGjDf/jch+NoBm04E1MH5l6+TWY6NdQCXf9HTN+I0u+ Xgg7tlitIqOUXveLm9O7jhYbJmzFL5p79HSROAS4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727918AbfL2R1O (ORCPT ); Sun, 29 Dec 2019 12:27:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:49140 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728060AbfL2R1L (ORCPT ); Sun, 29 Dec 2019 12:27:11 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 54C83207FF; Sun, 29 Dec 2019 17:27:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577640430; bh=CFq7QeTcEXfVevTxoQrg/wPsOlCDpo63+EilV2uVLvA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gmhdMeBlPZNx5Z+C+/0+EPDidP08z2c1GeYxHN/M2UEvc5h25QGQXuCecqz6vAPGj myuSBZ9E5r43flLMkF10XHrOTS8Qs/Fd4TdPTLvmDOXDSahlPOba9EGVlqlDkTUFaf QF8hzcOQl2+jHe+h9RtUvivsAILiHP3YhA3MU0dM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Will Deacon , Marc Zyngier Subject: [PATCH 4.14 154/161] KVM: arm64: Ensure params is initialised when looking up sys register Date: Sun, 29 Dec 2019 18:20:02 +0100 Message-Id: <20191229162448.691821033@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191229162355.500086350@linuxfoundation.org> References: <20191229162355.500086350@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Will Deacon commit 1ce74e96c2407df2b5867e5d45a70aacb8923c14 upstream. Commit 4b927b94d5df ("KVM: arm/arm64: vgic: Introduce find_reg_by_id()") introduced 'find_reg_by_id()', which looks up a system register only if the 'id' index parameter identifies a valid system register. As part of the patch, existing callers of 'find_reg()' were ported over to the new interface, but this breaks 'index_to_sys_reg_desc()' in the case that the initial lookup in the vCPU target table fails because we will then call into 'find_reg()' for the system register table with an uninitialised 'param' as the key to the lookup. GCC 10 is bright enough to spot this (amongst a tonne of false positives, but hey!): | arch/arm64/kvm/sys_regs.c: In function ‘index_to_sys_reg_desc.part.0.isra’: | arch/arm64/kvm/sys_regs.c:983:33: warning: ‘params.Op2’ may be used uninitialized in this function [-Wmaybe-uninitialized] | 983 | (u32)(x)->CRn, (u32)(x)->CRm, (u32)(x)->Op2); | [...] Revert the hunk of 4b927b94d5df which breaks 'index_to_sys_reg_desc()' so that the old behaviour of checking the index upfront is restored. Fixes: 4b927b94d5df ("KVM: arm/arm64: vgic: Introduce find_reg_by_id()") Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Cc: Link: https://lore.kernel.org/r/20191212094049.12437-1-will@kernel.org Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kvm/sys_regs.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1785,8 +1785,11 @@ static const struct sys_reg_desc *index_ if ((id & KVM_REG_ARM_COPROC_MASK) != KVM_REG_ARM64_SYSREG) return NULL; + if (!index_to_params(id, ¶ms)) + return NULL; + table = get_target_table(vcpu->arch.target, true, &num); - r = find_reg_by_id(id, ¶ms, table, num); + r = find_reg(¶ms, table, num); if (!r) r = find_reg(¶ms, sys_reg_descs, ARRAY_SIZE(sys_reg_descs));