From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH] kvm: x86: i8259: return initialized data on invalid-size
 read
Date: Mon, 30 Mar 2015 16:40:16 +0200
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References: <20150311111609.GG8544@dhcp-25-225.brq.redhat.com>
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	Gleb Natapov <gleb@kernel.org>, nadav.amit@gmail.com
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On 11/03/2015 12:16, Petr Matousek wrote:
> If data is read from PIC with invalid access size, the return data stays
> uninitialized even though success is returned. 
> 
> Fix this by always initializing the data.
> 
> Signed-off-by: Petr Matousek <pmatouse@redhat.com>
> Reported-by: Nadav Amit <nadav.amit@gmail.com>
> ---
>  arch/x86/kvm/i8259.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
> index cc31f7c..9541ba3 100644
> --- a/arch/x86/kvm/i8259.c
> +++ b/arch/x86/kvm/i8259.c
> @@ -507,6 +507,7 @@ static int picdev_read(struct kvm_pic *s,
>  		return -EOPNOTSUPP;
>  
>  	if (len != 1) {
> +		memset(val, 0, len);
>  		pr_pic_unimpl("non byte read\n");
>  		return 0;
>  	}
> 

Applied, thanks.

Paolo