linux-kernel - Re: [PATCH 3/4] KVM: x86/vPMU: fix undefined shift in intel_pmu

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 19 May 2017 15:31:42 +0200
From:   David Hildenbrand <david@...hat.com>
To:     Radim Krčmář <rkrcmar@...hat.com>,
        linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     Paolo Bonzini <pbonzini@...hat.com>,
        Dan Carpenter <dan.carpenter@...cle.com>
Subject: Re: [PATCH 3/4] KVM: x86/vPMU: fix undefined shift in
 intel_pmu_refresh()

On 18.05.2017 19:37, Radim Krčmář wrote:
> Static analysis noticed that pmu->nr_arch_gp_counters can be 32
> (INTEL_PMC_MAX_GENERIC) and therefore cannot be used to shift 'int'.
> 
> I didn't add BUILD_BUG_ON for it as we have a better checker.
> 
> Reported-by: Dan Carpenter <dan.carpenter@...cle.com>
> Fixes: 25462f7f5295 ("KVM: x86/vPMU: Define kvm_pmu_ops to support vPMU function dispatch")
> Signed-off-by: Radim Krčmář <rkrcmar@...hat.com>
> ---
>  arch/x86/kvm/pmu_intel.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kvm/pmu_intel.c b/arch/x86/kvm/pmu_intel.c
> index 9d4a8504a95a..5ab4a364348e 100644
> --- a/arch/x86/kvm/pmu_intel.c
> +++ b/arch/x86/kvm/pmu_intel.c
> @@ -294,7 +294,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
>  			((u64)1 << edx.split.bit_width_fixed) - 1;
>  	}
>  
> -	pmu->global_ctrl = ((1 << pmu->nr_arch_gp_counters) - 1) |
> +	pmu->global_ctrl = ((1ull << pmu->nr_arch_gp_counters) - 1) |
>  		(((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED);
>  	pmu->global_ctrl_mask = ~pmu->global_ctrl;
>  
> 

Reviewed-by: David Hildenbrand <david@...hat.com>

-- 

Thanks,

David