2019-03-19 22:21:23

by David Rientjes

Subject: [patch] kvm: svm: fix potential get_num_contig_pages overflow

get_num_contig_pages() could potentially overflow int so make its type
consistent with its usage.

Reported-by: Cfir Cohen <[email protected]>
Signed-off-by: David Rientjes <[email protected]>
---
arch/x86/kvm/svm.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6422,11 +6422,11 @@ static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
return ret;
}

-static int get_num_contig_pages(int idx, struct page **inpages,
- unsigned long npages)
+static unsigned long get_num_contig_pages(unsigned long idx,
+ struct page **inpages, unsigned long npages)
{
unsigned long paddr, next_paddr;
- int i = idx + 1, pages = 1;
+ unsigned long i = idx + 1, pages = 1;

/* find the number of contiguous pages starting from idx */
paddr = __sme_page_pa(inpages[idx]);
@@ -6445,12 +6445,12 @@ static int get_num_contig_pages(int idx, struct page **inpages,

static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
{
- unsigned long vaddr, vaddr_end, next_vaddr, npages, size;
+ unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i;
struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
struct kvm_sev_launch_update_data params;
struct sev_data_launch_update_data *data;
struct page **inpages;
- int i, ret, pages;
+ int ret;

if (!sev_guest(kvm))
return -ENOTTY;

2019-03-20 14:10:48

by Brijesh Singh

Subject: Re: [patch] kvm: svm: fix potential get_num_contig_pages overflow

On 3/19/19 5:19 PM, David Rientjes wrote:
> get_num_contig_pages() could potentially overflow int so make its type
> consistent with its usage.
>
> Reported-by: Cfir Cohen <[email protected]>
> Signed-off-by: David Rientjes <[email protected]>
> ---
> arch/x86/kvm/svm.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>

Reviewed-by: Brijesh Singh <[email protected]>

2019-04-04 21:27:45

by David Rientjes

Subject: Re: [patch] kvm: svm: fix potential get_num_contig_pages overflow

On Wed, 20 Mar 2019, Singh, Brijesh wrote:

> > get_num_contig_pages() could potentially overflow int so make its type
> > consistent with its usage.
> >
> > Reported-by: Cfir Cohen <[email protected]>
> > Signed-off-by: David Rientjes <[email protected]>
> > ---
> > arch/x86/kvm/svm.c | 10 +++++-----
> > 1 file changed, 5 insertions(+), 5 deletions(-)
> >
>
> Reviewed-by: Brijesh Singh <[email protected]>
>

Paolo, Radim, I don't see this in kvm.git, is it ready to be staged?

2019-04-05 18:50:39

by Paolo Bonzini

Subject: Re: [patch] kvm: svm: fix potential get_num_contig_pages overflow

On 19/03/19 23:19, David Rientjes wrote:
> get_num_contig_pages() could potentially overflow int so make its type
> consistent with its usage.
>
> Reported-by: Cfir Cohen <[email protected]>
> Signed-off-by: David Rientjes <[email protected]>
> ---
> arch/x86/kvm/svm.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -6422,11 +6422,11 @@ static int sev_launch_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
> return ret;
> }
>
> -static int get_num_contig_pages(int idx, struct page **inpages,
> - unsigned long npages)
> +static unsigned long get_num_contig_pages(unsigned long idx,
> + struct page **inpages, unsigned long npages)
> {
> unsigned long paddr, next_paddr;
> - int i = idx + 1, pages = 1;
> + unsigned long i = idx + 1, pages = 1;
>
> /* find the number of contiguous pages starting from idx */
> paddr = __sme_page_pa(inpages[idx]);
> @@ -6445,12 +6445,12 @@ static int get_num_contig_pages(int idx, struct page **inpages,
>
> static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
> {
> - unsigned long vaddr, vaddr_end, next_vaddr, npages, size;
> + unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i;
> struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
> struct kvm_sev_launch_update_data params;
> struct sev_data_launch_update_data *data;
> struct page **inpages;
> - int i, ret, pages;
> + int ret;
>
> if (!sev_guest(kvm))
> return -ENOTTY;
>

I had missed it, and now I've queued it.

Paolo