* [PATCH] KVM: s390: Check kvm pointer when testing KVM_CAP_S390_HPAGE_1M
@ 2024-04-19 16:07 Jean-Philippe Brucker
2024-04-19 16:43 ` Claudio Imbrenda
2024-04-22 8:25 ` Christian Borntraeger
0 siblings, 2 replies; 3+ messages in thread
From: Jean-Philippe Brucker @ 2024-04-19 16:07 UTC (permalink / raw)
To: borntraeger, frankja, imbrenda, david
Cc: hca, gor, agordeev, svens, kvm, linux-s390, Jean-Philippe Brucker
KVM allows issuing the KVM_CHECK_EXTENSION ioctl either on the /dev/kvm
fd or the VM fd. In the first case, kvm_vm_ioctl_check_extension() is
called with kvm==NULL. Ensure we don't dereference the pointer in that
case.
Fixes: 40ebdb8e59df ("KVM: s390: Make huge pages unavailable in ucontrol VMs")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
Only build-tested
---
arch/s390/kvm/kvm-s390.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 5147b943a864a..7721eb522f43d 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -587,7 +587,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
break;
case KVM_CAP_S390_HPAGE_1M:
r = 0;
- if (hpage && !kvm_is_ucontrol(kvm))
+ if (hpage && !(kvm && kvm_is_ucontrol(kvm)))
r = 1;
break;
case KVM_CAP_S390_MEM_OP:
--
2.44.0
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] KVM: s390: Check kvm pointer when testing KVM_CAP_S390_HPAGE_1M
2024-04-19 16:07 [PATCH] KVM: s390: Check kvm pointer when testing KVM_CAP_S390_HPAGE_1M Jean-Philippe Brucker
@ 2024-04-19 16:43 ` Claudio Imbrenda
2024-04-22 8:25 ` Christian Borntraeger
1 sibling, 0 replies; 3+ messages in thread
From: Claudio Imbrenda @ 2024-04-19 16:43 UTC (permalink / raw)
To: Jean-Philippe Brucker
Cc: borntraeger, frankja, david, hca, gor, agordeev, svens, kvm,
linux-s390
On Fri, 19 Apr 2024 17:07:24 +0100
Jean-Philippe Brucker <jean-philippe@linaro.org> wrote:
> KVM allows issuing the KVM_CHECK_EXTENSION ioctl either on the /dev/kvm
> fd or the VM fd. In the first case, kvm_vm_ioctl_check_extension() is
> called with kvm==NULL. Ensure we don't dereference the pointer in that
> case.
>
> Fixes: 40ebdb8e59df ("KVM: s390: Make huge pages unavailable in ucontrol VMs")
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> ---
> Only build-tested
> ---
> arch/s390/kvm/kvm-s390.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 5147b943a864a..7721eb522f43d 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -587,7 +587,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> break;
> case KVM_CAP_S390_HPAGE_1M:
> r = 0;
> - if (hpage && !kvm_is_ucontrol(kvm))
> + if (hpage && !(kvm && kvm_is_ucontrol(kvm)))
> r = 1;
> break;
> case KVM_CAP_S390_MEM_OP:
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] KVM: s390: Check kvm pointer when testing KVM_CAP_S390_HPAGE_1M
2024-04-19 16:07 [PATCH] KVM: s390: Check kvm pointer when testing KVM_CAP_S390_HPAGE_1M Jean-Philippe Brucker
2024-04-19 16:43 ` Claudio Imbrenda
@ 2024-04-22 8:25 ` Christian Borntraeger
1 sibling, 0 replies; 3+ messages in thread
From: Christian Borntraeger @ 2024-04-22 8:25 UTC (permalink / raw)
To: Jean-Philippe Brucker, frankja, imbrenda, david
Cc: hca, gor, agordeev, svens, kvm, linux-s390
Am 19.04.24 um 18:07 schrieb Jean-Philippe Brucker:
> KVM allows issuing the KVM_CHECK_EXTENSION ioctl either on the /dev/kvm
> fd or the VM fd. In the first case, kvm_vm_ioctl_check_extension() is
> called with kvm==NULL. Ensure we don't dereference the pointer in that
> case.
>
> Fixes: 40ebdb8e59df ("KVM: s390: Make huge pages unavailable in ucontrol VMs")
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
thanks applied.
> ---
> Only build-tested
> ---
> arch/s390/kvm/kvm-s390.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 5147b943a864a..7721eb522f43d 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -587,7 +587,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> break;
> case KVM_CAP_S390_HPAGE_1M:
> r = 0;
> - if (hpage && !kvm_is_ucontrol(kvm))
> + if (hpage && !(kvm && kvm_is_ucontrol(kvm)))
> r = 1;
> break;
> case KVM_CAP_S390_MEM_OP:
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-04-22 8:25 UTC | newest]
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2024-04-19 16:07 [PATCH] KVM: s390: Check kvm pointer when testing KVM_CAP_S390_HPAGE_1M Jean-Philippe Brucker
2024-04-19 16:43 ` Claudio Imbrenda
2024-04-22 8:25 ` Christian Borntraeger
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