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=-12.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 D58B3C43461 for ; Tue, 15 Sep 2020 14:32:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 994DF22AAC for ; Tue, 15 Sep 2020 14:32:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600180343; bh=kVX2LVxTE0Lh2FLDBjqmpIOxnLhXCQzDjFb/1KniRLU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=PerCzwjYu2IYeiJFiPSNYc94ezLoyyzo4AxRjlpJMYvAx2Gi0WZcG0CzN43p603HJ Dak7t1F3eLHwmlUdoBVMQm62iApySU8+lIQAgZj/sjNoG234mRzWgqOpf+RLtF+Hzi n2anF2D8t3hL+jka02ivePpD+7qDdRPF7AYgGeBE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726890AbgIOOcW (ORCPT ); Tue, 15 Sep 2020 10:32:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:46458 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727041AbgIOOba (ORCPT ); Tue, 15 Sep 2020 10:31:30 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 5F4F122B4E; Tue, 15 Sep 2020 14:23:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600179785; bh=kVX2LVxTE0Lh2FLDBjqmpIOxnLhXCQzDjFb/1KniRLU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yYy6XfGGPEnvvyUSOcinsetRg1x0q6WFl4SrLy4pQS9/OIfQQsgGoVJwIArNYUlYP HCUPDFvpaTA1id52Kjd4JE/PUnUXRfsTd7/ScyRzJz70Dmi/UECRmvmzuaRBzGLjns p8U8Hp/IwcnGPILdPD42PZ9w/rvQCzI9zvVVUj/w= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Rustam Kovhaev , Vitaly Kuznetsov , Paolo Bonzini , syzbot+f196caa45793d6374707@syzkaller.appspotmail.com Subject: [PATCH 5.4 117/132] KVM: fix memory leak in kvm_io_bus_unregister_dev() Date: Tue, 15 Sep 2020 16:13:39 +0200 Message-Id: <20200915140649.971767305@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200915140644.037604909@linuxfoundation.org> References: <20200915140644.037604909@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: Rustam Kovhaev commit f65886606c2d3b562716de030706dfe1bea4ed5e upstream. when kmalloc() fails in kvm_io_bus_unregister_dev(), before removing the bus, we should iterate over all other devices linked to it and call kvm_iodevice_destructor() for them Fixes: 90db10434b16 ("KVM: kvm_io_bus_unregister_dev() should never fail") Cc: stable@vger.kernel.org Reported-and-tested-by: syzbot+f196caa45793d6374707@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=f196caa45793d6374707 Signed-off-by: Rustam Kovhaev Reviewed-by: Vitaly Kuznetsov Message-Id: <20200907185535.233114-1-rkovhaev@gmail.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- virt/kvm/kvm_main.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4010,7 +4010,7 @@ int kvm_io_bus_register_dev(struct kvm * void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, struct kvm_io_device *dev) { - int i; + int i, j; struct kvm_io_bus *new_bus, *bus; bus = kvm_get_bus(kvm, bus_idx); @@ -4027,17 +4027,20 @@ void kvm_io_bus_unregister_dev(struct kv new_bus = kmalloc(struct_size(bus, range, bus->dev_count - 1), GFP_KERNEL_ACCOUNT); - if (!new_bus) { + if (new_bus) { + memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range)); + new_bus->dev_count--; + memcpy(new_bus->range + i, bus->range + i + 1, + (new_bus->dev_count - i) * sizeof(struct kvm_io_range)); + } else { pr_err("kvm: failed to shrink bus, removing it completely\n"); - goto broken; + for (j = 0; j < bus->dev_count; j++) { + if (j == i) + continue; + kvm_iodevice_destructor(bus->range[j].dev); + } } - memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range)); - new_bus->dev_count--; - memcpy(new_bus->range + i, bus->range + i + 1, - (new_bus->dev_count - i) * sizeof(struct kvm_io_range)); - -broken: rcu_assign_pointer(kvm->buses[bus_idx], new_bus); synchronize_srcu_expedited(&kvm->srcu); kfree(bus);