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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 AEA5EC169C4 for ; Mon, 11 Feb 2019 14:34:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7B164204EC for ; Mon, 11 Feb 2019 14:34:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895660; bh=kFi2/JZpQSaYq/fAbyFCu0cZqUCHqBMqtoY0V0ukxpM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CVuxETwVdiEmNivYZyWVKUcOtAmjG1LO3J0G/j854/tvmeOWDYLbR1CjHMJTuGee+ gFTYrPl6rL7w1lE6mz9LK/lr4DfPnyMjaDN0UUuq4WYTAJ91/meg1UBVOq+vnFaG27 ljELZFPsCyYRU0KzNLlkpPlDGOVc9Fj0GFLsKfrw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730822AbfBKOeT (ORCPT ); Mon, 11 Feb 2019 09:34:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:42460 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730806AbfBKOeR (ORCPT ); Mon, 11 Feb 2019 09:34:17 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 A48EF204EC; Mon, 11 Feb 2019 14:34:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895656; bh=kFi2/JZpQSaYq/fAbyFCu0cZqUCHqBMqtoY0V0ukxpM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cJ06OSFQtKGzZ2bW9qNjOwrv865xeFqjzAC7RgqNmajnx8V+c4GdhddPUSuqdtXVC 7mGpetbfwFonSvOLOy5RF4HqYOtwzOvbogIxYqmTGnqy+GFfods31ekCt3ouyZMva0 zn5EmjoCrP9h2GiPSA22K+70Gc+C7sR88JdTz+g0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Cfir Cohen , Jim Mattson , Peter Shier , Krish Sadhukhan , Sean Christopherson , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Sasha Levin Subject: [PATCH 4.20 248/352] kvm: Change offset in kvm_write_guest_offset_cached to unsigned Date: Mon, 11 Feb 2019 15:17:55 +0100 Message-Id: <20190211141902.901779005@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190211141846.543045703@linuxfoundation.org> References: <20190211141846.543045703@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 7a86dab8cf2f0fdf508f3555dddfc236623bff60 ] Since the offset is added directly to the hva from the gfn_to_hva_cache, a negative offset could result in an out of bounds write. The existing BUG_ON only checks for addresses beyond the end of the gfn_to_hva_cache, not for addresses before the start of the gfn_to_hva_cache. Note that all current call sites have non-negative offsets. Fixes: 4ec6e8636256 ("kvm: Introduce kvm_write_guest_offset_cached()") Reported-by: Cfir Cohen Signed-off-by: Jim Mattson Reviewed-by: Cfir Cohen Reviewed-by: Peter Shier Reviewed-by: Krish Sadhukhan Reviewed-by: Sean Christopherson Signed-off-by: Radim Krčmář Signed-off-by: Sasha Levin --- include/linux/kvm_host.h | 3 ++- virt/kvm/kvm_main.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index c926698040e0..a03d5e264e5e 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -694,7 +694,8 @@ int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data, int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc, void *data, unsigned long len); int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc, - void *data, int offset, unsigned long len); + void *data, unsigned int offset, + unsigned long len); int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc, gpa_t gpa, unsigned long len); int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 2679e476b6c3..065ee2fb4034 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1965,7 +1965,8 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc, EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init); int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc, - void *data, int offset, unsigned long len) + void *data, unsigned int offset, + unsigned long len) { struct kvm_memslots *slots = kvm_memslots(kvm); int r; -- 2.19.1