From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934046AbZIDUOb (ORCPT ); Fri, 4 Sep 2009 16:14:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934034AbZIDUO2 (ORCPT ); Fri, 4 Sep 2009 16:14:28 -0400 Received: from kroah.org ([198.145.64.141]:36154 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934004AbZIDUOX (ORCPT ); Fri, 4 Sep 2009 16:14:23 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Fri Sep 4 13:08:52 2009 Message-Id: <20090904200852.685554919@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Fri, 04 Sep 2009 13:07:28 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Sheng Yang , Avi Kivity , Dave Hansen , Avi Kivity Subject: [patch 16/48] KVM: Reduce stack usage in kvm_arch_vcpu_ioctl() References: <20090904200712.724048145@mini.kroah.org> Content-Disposition: inline; filename=kvm-reduce-stack-usage-in-kvm_arch_vcpu_ioctl.patch In-Reply-To: <20090904201112.GA8274@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Dave Hansen (cherry picked from commit b772ff362ec6b821c8a5227a3355e263f917bfad) [sheng: fix KVM_GET_LAPIC using wrong size] Signed-off-by: Dave Hansen Signed-off-by: Sheng Yang Signed-off-by: Avi Kivity Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/x86.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1303,28 +1303,33 @@ long kvm_arch_vcpu_ioctl(struct file *fi struct kvm_vcpu *vcpu = filp->private_data; void __user *argp = (void __user *)arg; int r; + struct kvm_lapic_state *lapic = NULL; switch (ioctl) { case KVM_GET_LAPIC: { - struct kvm_lapic_state lapic; + lapic = kzalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL); - memset(&lapic, 0, sizeof lapic); - r = kvm_vcpu_ioctl_get_lapic(vcpu, &lapic); + r = -ENOMEM; + if (!lapic) + goto out; + r = kvm_vcpu_ioctl_get_lapic(vcpu, lapic); if (r) goto out; r = -EFAULT; - if (copy_to_user(argp, &lapic, sizeof lapic)) + if (copy_to_user(argp, lapic, sizeof(struct kvm_lapic_state))) goto out; r = 0; break; } case KVM_SET_LAPIC: { - struct kvm_lapic_state lapic; - + lapic = kmalloc(sizeof(struct kvm_lapic_state), GFP_KERNEL); + r = -ENOMEM; + if (!lapic) + goto out; r = -EFAULT; - if (copy_from_user(&lapic, argp, sizeof lapic)) + if (copy_from_user(lapic, argp, sizeof(struct kvm_lapic_state))) goto out; - r = kvm_vcpu_ioctl_set_lapic(vcpu, &lapic);; + r = kvm_vcpu_ioctl_set_lapic(vcpu, lapic); if (r) goto out; r = 0; @@ -1422,6 +1427,8 @@ long kvm_arch_vcpu_ioctl(struct file *fi r = -EINVAL; } out: + if (lapic) + kfree(lapic); return r; }