From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762077AbZEFV6a (ORCPT ); Wed, 6 May 2009 17:58:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761391AbZEFVya (ORCPT ); Wed, 6 May 2009 17:54:30 -0400 Received: from kroah.org ([198.145.64.141]:56970 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761337AbZEFVy0 (ORCPT ); Wed, 6 May 2009 17:54:26 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Wed May 6 14:47:56 2009 Message-Id: <20090506214756.590967464@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Wed, 06 May 2009 14:45:38 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org, jejb@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jan Kiszka , Avi Kivity , Chris Wright Subject: [patch 10/58] KVM: Fix overlapping check for memory slots References: <20090506214528.660389067@mini.kroah.org> Content-Disposition: inline; filename=kvm-fix-overlapping-check-for-memory-slots.patch In-Reply-To: <20090506215017.GA21981@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.29-stable review patch. If anyone has any objections, please let us know. ------------------ From: Jan Kiszka upstream commit: 4cd481f68dde99ac416003b825c835f71e364393 When checking for overlapping slots on registration of a new one, kvm currently also considers zero-length (ie. deleted) slots and rejects requests incorrectly. This finally denies user space from joining slots. Fix the check by skipping deleted slots and advertise this via a KVM_CAP_JOIN_MEMORY_REGIONS_WORKS. Cc: stable@kernel.org Signed-off-by: Jan Kiszka Signed-off-by: Avi Kivity Signed-off-by: Chris Wright --- include/linux/kvm.h | 2 ++ virt/kvm/kvm_main.c | 3 ++- 2 files changed, 4 insertions(+), 1 deletion(-) --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -396,6 +396,8 @@ struct kvm_trace_rec { #ifdef __KVM_HAVE_USER_NMI #define KVM_CAP_USER_NMI 22 #endif +/* Another bug in KVM_SET_USER_MEMORY_REGION fixed: */ +#define KVM_CAP_JOIN_MEMORY_REGIONS_WORKS 30 /* * ioctls for VM fds --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1005,7 +1005,7 @@ int __kvm_set_memory_region(struct kvm * for (i = 0; i < KVM_MEMORY_SLOTS; ++i) { struct kvm_memory_slot *s = &kvm->memslots[i]; - if (s == memslot) + if (s == memslot || !s->npages) continue; if (!((base_gfn + npages <= s->base_gfn) || (base_gfn >= s->base_gfn + s->npages))) @@ -1997,6 +1997,7 @@ static long kvm_dev_ioctl_check_extensio switch (arg) { case KVM_CAP_USER_MEMORY: case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: + case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS: return 1; default: break;