Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757056AbdLUAak (ORCPT ); Wed, 20 Dec 2017 19:30:40 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45670 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756622AbdLUAag (ORCPT ); Wed, 20 Dec 2017 19:30:36 -0500 Subject: Re: [PATCH linux-next] KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs() To: Eric Biggers , kvm@vger.kernel.org Cc: rkrcmar@redhat.com, tianyu.lan@intel.com, christoffer.dall@linaro.org, x86@kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, Eric Biggers , Stephen Rothwell , Linux-Next Mailing List References: <001a1148cc3acf967c0560c7b760@google.com> <20171221002427.82325-1-ebiggers3@gmail.com> From: Paolo Bonzini Message-ID: <5e98adf7-809f-3b98-e8fc-6ba89e2777cf@redhat.com> Date: Thu, 21 Dec 2017 01:30:30 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: <20171221002427.82325-1-ebiggers3@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Thu, 21 Dec 2017 00:30:35 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1174 Lines: 34 On 21/12/2017 01:24, Eric Biggers wrote: > From: Eric Biggers > > Due to a bad merge resolution between commit f29810335965 ("KVM/x86: > Check input paging mode when cs.l is set") and commit b4ef9d4e8cb8 > ("KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_set_sregs"), > there is a case in kvm_arch_vcpu_ioctl_set_sregs() where vcpu_put() is > not called after vcpu_get(). Fix it. > > Reported-by: syzbot > Signed-off-by: Eric Biggers > --- > arch/x86/kvm/x86.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index ea3a98196753..f4e8b5089b28 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -7624,7 +7624,7 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, > goto out; > > if (kvm_valid_sregs(vcpu, sregs)) > - return -EINVAL; > + goto out; > > apic_base_msr.data = sregs->apic_base; > apic_base_msr.host_initiated = true; > Thanks very much Eric, that was fast! Adding Stephen and the linux-next mailing list to Cc. Adding the kvm/master tree has already paid off. Paolo