From patchwork Thu Dec 13 21:10:21 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jim Mattson X-Patchwork-Id: 10729919 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 D200F1759 for ; Thu, 13 Dec 2018 21:10:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C57BA2C650 for ; Thu, 13 Dec 2018 21:10:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B9E5E2C73F; Thu, 13 Dec 2018 21:10:38 +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=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 689742C650 for ; Thu, 13 Dec 2018 21:10:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726533AbeLMVKh (ORCPT ); Thu, 13 Dec 2018 16:10:37 -0500 Received: from mail-pf1-f202.google.com ([209.85.210.202]:55648 "EHLO mail-pf1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726435AbeLMVKg (ORCPT ); Thu, 13 Dec 2018 16:10:36 -0500 Received: by mail-pf1-f202.google.com with SMTP id s71so2554627pfi.22 for ; Thu, 13 Dec 2018 13:10:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=1Wk780NEE7wrpsiZPoCc2skcF5oK0mGyYIa2/BCd8uE=; b=Amtg14Gic9uvtlpxfsz8jc2oRF6da95Zfwk7nE6h/KLBL1IXlquhRBwwNDh5f8ArIj IbkCNgILh/CReorIfQ77bNLCotzS6okWCkUqDVRtB6EIc+5p1upYipMw55isGH4kd9Ht u9XZZr/fFlEnekvRADSMNlC65Pm3hxDC9qRuqBW0J6lLvTRkbJ78Xq5qGqwgRsj+b5K2 0l0bV/A72ME/TXWmQ2306UlvEUCQeQY0D6MDOUqp5yQfoeqr+LDrmCJhJTiZyi9E5j2g z7D+q/Qks7Nzp+QvjTcL22TbrNVrzldjkVz1+yfkEoxUN1kqXIhGarEesEF/MnT6L1kg V+pA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=1Wk780NEE7wrpsiZPoCc2skcF5oK0mGyYIa2/BCd8uE=; b=o+5tBSa9qVYtA18ZvNtFNb+92j/i6uB4rx11uiJnNSC5LdF2xlBLhnCgBKzL3YXt/x iEzFr8NnP60ER2YZZF+ARx727wPmn0EBYVyPpWbP9/WmpSQNNZXYqwZ29ZiuOrcSnQ3b h5/5luwl0qAWyIgL61mZ7CtusmJQHszfRX0Dn5Y5XOluZqEK9Zyoxpet2euWYv22+Jiw Fe0rLO4Iddjn5Q01HmTv0bLak+0i5jlCIy0SoTVjcuOktojnClND24f4dbUPbDMWaM2B QDz7PWcQjARf7CytBlJG32kTLLO4SSRw6i5EsapSNYLwe4bxLWuIZa2T6y+kp3SjIutD D/Mg== X-Gm-Message-State: AA+aEWbj9hufn6iu6Ephe8xSXgf/MhFiA7uD7DUCwP5fKTBCWk8Uuf8H 0TzsGGfYHCmau7WBrdxIdTYA6NQyVIvQKtvQ2y/4t6dFqTD/DerT1CzX0gnC1PiN/D0RJDMBWF/ 2sg/G4auir4592NW43dbiqZWtdunam776jF9U/T+khDwfQFvPpKXmXwt9YjlhUqQ= X-Google-Smtp-Source: AFSGD/U7J0iVWHhW6i8mZAp9NJFIC6ReYZNnPidj6s7smMMqL90rBIgpZMZB858+GoGSB91i5d6DQ3uO0ZwN3w== X-Received: by 2002:a62:2258:: with SMTP id i85mr259874pfi.89.1544735435738; Thu, 13 Dec 2018 13:10:35 -0800 (PST) Date: Thu, 13 Dec 2018 13:10:21 -0800 Message-Id: <20181213211021.202476-1-jmattson@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.20.0.rc2.403.gdbc3b29805-goog Subject: [PATCH] kvm: Change offset in kvm_write_guest_offset_cached to unsigned From: Jim Mattson To: kvm@vger.kernel.org Cc: Jim Mattson , Cfir Cohen , Peter Shier Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Avoid potential out-of-bounds writes due to negative offsets. Note that all current call sites are fine. 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 --- 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 c926698040e0d..a03d5e264e5e7 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 2679e476b6c39..065ee2fb40340 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;