From nobody Mon May 11 04:52:15 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33AA1C433FE for ; Thu, 14 Apr 2022 06:21:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240059AbiDNGXm (ORCPT ); Thu, 14 Apr 2022 02:23:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240026AbiDNGXf (ORCPT ); Thu, 14 Apr 2022 02:23:35 -0400 Received: from mail-pl1-x629.google.com (mail-pl1-x629.google.com [IPv6:2607:f8b0:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F14404D24A; Wed, 13 Apr 2022 23:21:11 -0700 (PDT) Received: by mail-pl1-x629.google.com with SMTP id n18so3867418plg.5; Wed, 13 Apr 2022 23:21:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id; bh=v6BSL8VhVmwIej2fDS4fILub4T69woLAa8tFuzppLBk=; b=myoGwm2G1MSWxH52mFS6PB//GYIp24Zl7kzfWhLsbgDggF7p3Uq899B13XQH5s71gu HHFqo6T+QWWaM66hqv+AyVlDLgA/ey/zDE2HM5L7WTYH4D2kU2LDq9fB6nM1HjNmFtCp hEqP6Z0xmeWKJqmVJ2bT6wT/f9FTWcSfZT1ed9mXOqC/ZtcS0ppQJyMNs4teGiBy2J3R nGsG4/HlF/Up6SkA56i2FJJZzhjZLHyUV95Ii+3tbh5yryu0XvRuWwPUFVqgq9b+ij1o A54iIEeEkJ81az7JwRj8iFxQMs2XOc+AC/ZlQRYtkaZZIUz1liYyXYTwdzsiLOPqesFB Glmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=v6BSL8VhVmwIej2fDS4fILub4T69woLAa8tFuzppLBk=; b=13dzXlrVJkwyOBkNc1y7IPQcywIMm3woZQcKbkDOKa7EtCkYMSini3AOaN/HMqQthp X/f0GooRlanmIR/YiqrqGnLRgLlN1O5A51cRVF6qwsPJ2u9oFL8W02y4Qobg1tGkix4K tCVOoO9mRcdpXhVe7sSFIW0iGmTtj4+IETHVk07B9auikQBEVe/FlJGZUK0dC+HvLLyD cJ1n2HRJ0/yar2g4Vghx+uyfi+CqYmjehLvS2XA/E6/d6VbP98hkzHSdS9U7E/txgcI8 6iJfyj4WG2B3R0O2infPBmMeeNp+94bfFdlO3jW+3WjxABuC7NES88cKd8PIUOq2rX8a HlRQ== X-Gm-Message-State: AOAM532ggi1s5ONqX3eODP269Ue7cHc2Xnp+lbCn32gXqTWUNlIEmUPN UwsvVvT6DZj2AAuGsijVCYE= X-Google-Smtp-Source: ABdhPJx/+VfCKqnYmadJUeIHFXxCThNG7ojieyEdrIdWyLC4NUzoCeJQJbvhMw0o07fEgwbpqK4R8g== X-Received: by 2002:a17:90b:314a:b0:1cd:3a73:3a99 with SMTP id ip10-20020a17090b314a00b001cd3a733a99mr2641203pjb.189.1649917270729; Wed, 13 Apr 2022 23:21:10 -0700 (PDT) Received: from localhost.localdomain ([119.3.119.18]) by smtp.googlemail.com with ESMTPSA id nl17-20020a17090b385100b001c70883f6ccsm5042588pjb.36.2022.04.13.23.21.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 Apr 2022 23:21:10 -0700 (PDT) From: Xiaomeng Tong To: mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org, akpm@linux-foundation.org, liam.howlett@oracle.com, david@redhat.com, maz@kernel.org, Felix.Kuehling@amd.com, maciej.szmigiero@oracle.com, apopple@nvidia.com, bharata@linux.ibm.com, linuxram@us.ibm.com Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Xiaomeng Tong , stable@vger.kernel.org Subject: [RESEND][PATCH] KVM: PPC: Book3S HV: fix incorrect NULL check on list iterator Date: Thu, 14 Apr 2022 14:21:03 +0800 Message-Id: <20220414062103.8153-1-xiam0nd.tong@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The bug is here: if (!p) return ret; The list iterator value 'p' will *always* be set and non-NULL by list_for_each_entry(), so it is incorrect to assume that the iterator value will be NULL if the list is empty or no element is found. To fix the bug, Use a new value 'iter' as the list iterator, while use the old value 'p' as a dedicated variable to point to the found element. Cc: stable@vger.kernel.org Fixes: dfaa973ae9605 ("KVM: PPC: Book3S HV: In H_SVM_INIT_DONE, migrate rem= aining normal-GFNs to secure-GFNs") Signed-off-by: Xiaomeng Tong --- arch/powerpc/kvm/book3s_hv_uvmem.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_h= v_uvmem.c index e414ca44839f..0cb20ee6a632 100644 --- a/arch/powerpc/kvm/book3s_hv_uvmem.c +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c @@ -360,13 +360,15 @@ static bool kvmppc_gfn_is_uvmem_pfn(unsigned long gfn= , struct kvm *kvm, static bool kvmppc_next_nontransitioned_gfn(const struct kvm_memory_slot *= memslot, struct kvm *kvm, unsigned long *gfn) { - struct kvmppc_uvmem_slot *p; + struct kvmppc_uvmem_slot *p =3D NULL, *iter; bool ret =3D false; unsigned long i; =20 - list_for_each_entry(p, &kvm->arch.uvmem_pfns, list) - if (*gfn >=3D p->base_pfn && *gfn < p->base_pfn + p->nr_pfns) + list_for_each_entry(iter, &kvm->arch.uvmem_pfns, list) + if (*gfn >=3D iter->base_pfn && *gfn < iter->base_pfn + iter->nr_pfns) { + p =3D iter; break; + } if (!p) return ret; /* --=20 2.17.1