From patchwork Wed Dec 19 18:03:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 10737957 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8356C6C2 for ; Wed, 19 Dec 2018 18:32:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7342B2B5B5 for ; Wed, 19 Dec 2018 18:32:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 675312B5B9; Wed, 19 Dec 2018 18:32:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 0A0C52B5B5 for ; Wed, 19 Dec 2018 18:32:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=0KsWaIJzygXh3S7UMwUOkkc2TLNU3SlVlNyDk6AQdNQ=; b=SXo4vAVkZYaDUj 9OePBgEYjGWp2KU5jYK/ZXGYFN1ZmCjgQ0AcsE/5CiBhGogxJReKzV4TtYaNt+shyLgIMB0GeOgYg cnTTkR80ni0MTyg+Rj/SBEMp55H60gSlqUOAlh7PoB2B5PWe5M7ibSVO5BT+MwnhlgWDkshn1Krlb NUet4w86KJxL7L1UfLIP8IPl7pqYsNVPCqRnZntg15HUEpim9umbDd4utbjWP70+VOlB15bC+sOgi EqbgC1Xn5FWLDihQFOYLD0r0ItzAzIvI+Nnhf1HrxcoJuC4Mk+tTIfzv4kct83RvYQqb/lXqFc0C5 obmNXYuwNBH+Skf1Zugw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gZge3-00072U-09; Wed, 19 Dec 2018 18:32:35 +0000 Received: from merlin.infradead.org ([2001:8b0:10b:1231::1]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gZgdK-0006KA-K6 for linux-arm-kernel@bombadil.infradead.org; Wed, 19 Dec 2018 18:31:50 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=35Rinf4PGd/vuk8dUaG2mWs7r3aN9Wv2VyOBHHuwZtk=; b=DX1Q2VRNokWfIIT5iabEZuipxE 8EFW1Susb+jGnWEjBM9tkYJrbKNwAhPFFp9bcXZr7uWMymAdLK7+CB/GmLcOhr8rHl85BEH2IvW1P 4e1drDbCoZEkI04oN6sWlITvCEmu4jIPSkz10Ewe3BU6bjR0GnxNM8XS332GXAOcGbK9AnxI8qo7k FbmRkb3LAPvaXOXe61bArj0BYDvl/VCVtqiSpfOzTiVETDWGejLH+9lOJldSvHVGhn5l3ZKGvnHQH uVTq+BWdZrM7c4dYPI4KME+zpEslZHaqPlAMxQ3qnUwO0dCH6Ufu8l4JyreWzUjICau2xks8lwREw 281jbmfg==; Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by merlin.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gZgDX-0000Tg-Il for linux-arm-kernel@lists.infradead.org; Wed, 19 Dec 2018 18:05:12 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BB3321684; Wed, 19 Dec 2018 10:04:56 -0800 (PST) Received: from filthy-habits.cambridge.arm.com (filthy-habits.cambridge.arm.com [10.1.196.62]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3C1293F675; Wed, 19 Dec 2018 10:04:54 -0800 (PST) From: Marc Zyngier To: Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= Subject: [PATCH 17/28] KVM: arm/arm64: vgic: Fix off-by-one bug in vgic_get_irq() Date: Wed, 19 Dec 2018 18:03:38 +0000 Message-Id: <20181219180349.242681-18-marc.zyngier@arm.com> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181219180349.242681-1-marc.zyngier@arm.com> References: <20181219180349.242681-1-marc.zyngier@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181219_130511_704514_F1F73B13 X-CRM114-Status: GOOD ( 17.80 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Punit Agrawal , kvm@vger.kernel.org, Julien Thierry , "Gustavo A . R . Silva" , Will Deacon , Christoffer Dall , linux-arm-kernel@lists.infradead.org, punitagrawal@gmail.com, =?utf-8?q?Ale?= =?utf-8?q?x_Benn=C3=A9e?= , kvmarm@lists.cs.columbia.edu, Suzuki Poulose , Lukas Braun Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: "Gustavo A. R. Silva" When using the nospec API, it should be taken into account that: "...if the CPU speculates past the bounds check then * array_index_nospec() will clamp the index within the range of [0, * size)." The above is part of the header for macro array_index_nospec() in linux/nospec.h Now, in this particular case, if intid evaluates to exactly VGIC_MAX_SPI or to exaclty VGIC_MAX_PRIVATE, the array_index_nospec() macro ends up returning VGIC_MAX_SPI - 1 or VGIC_MAX_PRIVATE - 1 respectively, instead of VGIC_MAX_SPI or VGIC_MAX_PRIVATE, which, based on the original logic: /* SGIs and PPIs */ if (intid <= VGIC_MAX_PRIVATE) return &vcpu->arch.vgic_cpu.private_irqs[intid]; /* SPIs */ if (intid <= VGIC_MAX_SPI) return &kvm->arch.vgic.spis[intid - VGIC_NR_PRIVATE_IRQS]; are valid values for intid. Fix this by calling array_index_nospec() macro with VGIC_MAX_PRIVATE + 1 and VGIC_MAX_SPI + 1 as arguments for its parameter size. Fixes: 41b87599c743 ("KVM: arm/arm64: vgic: fix possible spectre-v1 in vgic_get_irq()") Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva [dropped the SPI part which was fixed separately] Signed-off-by: Marc Zyngier --- virt/kvm/arm/vgic/vgic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c index 8ab0491bcc94..f884a54b2601 100644 --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -103,7 +103,7 @@ struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu, { /* SGIs and PPIs */ if (intid <= VGIC_MAX_PRIVATE) { - intid = array_index_nospec(intid, VGIC_MAX_PRIVATE); + intid = array_index_nospec(intid, VGIC_MAX_PRIVATE + 1); return &vcpu->arch.vgic_cpu.private_irqs[intid]; }