This is a note to let you know that I've just added the patch titled
KVM: Ensure all vcpus are consistent with in-kernel irqchip settings
to the 3.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-ensure-all-vcpus-are-consistent-with-in-kernel-irqchip-settings.patch
and it can be found in the queue-3.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From jslaby@xxxxxxx Mon Apr 1 16:37:16 2013
From: Jiri Slaby <jslaby@xxxxxxx>
Date: Tue, 19 Mar 2013 12:36:55 +0100
Subject: KVM: Ensure all vcpus are consistent with in-kernel irqchip settings
To: gregkh@xxxxxxxxxxxxxxxxxxx
Cc: jirislaby@xxxxxxxxx, stable@xxxxxxxxxxxxxxx, Avi Kivity <avi@xxxxxxxxxx>, Michael Ellerman <michael@xxxxxxxxxxxxxx>, Jiri Slaby <jslaby@xxxxxxx>
Message-ID: <1363693019-14812-10-git-send-email-jslaby@xxxxxxx>
From: Avi Kivity <avi@xxxxxxxxxx>
commit 3e515705a1f46beb1c942bb8043c16f8ac7b1e9e upstream.
If some vcpus are created before KVM_CREATE_IRQCHIP, then
irqchip_in_kernel() and vcpu->arch.apic will be inconsistent, leading
to potential NULL pointer dereferences.
Fix by:
- ensuring that no vcpus are installed when KVM_CREATE_IRQCHIP is called
- ensuring that a vcpu has an apic if it is installed after KVM_CREATE_IRQCHIP
This is somewhat long winded because vcpu->arch.apic is created without
kvm->lock held.
Based on earlier patch by Michael Ellerman.
Signed-off-by: Michael Ellerman <michael@xxxxxxxxxxxxxx>
Signed-off-by: Avi Kivity <avi@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/ia64/kvm/kvm-ia64.c | 5 +++++
arch/x86/kvm/x86.c | 8 ++++++++
include/linux/kvm_host.h | 7 +++++++
virt/kvm/kvm_main.c | 4 ++++
4 files changed, 24 insertions(+)
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -1168,6 +1168,11 @@ out:
#define PALE_RESET_ENTRY 0x80000000ffffffb0UL
+bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu)
+{
+ return irqchip_in_kernel(vcpu->kcm) == (vcpu->arch.apic != NULL);
+}
+
int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu *v;
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3410,6 +3410,9 @@ long kvm_arch_vm_ioctl(struct file *filp
r = -EEXIST;
if (kvm->arch.vpic)
goto create_irqchip_unlock;
+ r = -EINVAL;
+ if (atomic_read(&kvm->online_vcpus))
+ goto create_irqchip_unlock;
r = -ENOMEM;
vpic = kvm_create_pic(kvm);
if (vpic) {
@@ -6189,6 +6192,11 @@ void kvm_arch_check_processor_compat(voi
kvm_x86_ops->check_processor_compatibility(rtn);
}
+bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu)
+{
+ return irqchip_in_kernel(vcpu->kvm) == (vcpu->arch.apic != NULL);
+}
+
int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
struct page *page;
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -736,6 +736,13 @@ static inline bool kvm_vcpu_is_bsp(struc
{
return vcpu->kvm->bsp_vcpu_id == vcpu->vcpu_id;
}
+
+bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu);
+
+#else
+
+static inline bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu) { return true; }
+
#endif
#ifdef __KVM_HAVE_DEVICE_ASSIGNMENT
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1619,6 +1619,10 @@ static int kvm_vm_ioctl_create_vcpu(stru
goto vcpu_destroy;
mutex_lock(&kvm->lock);
+ if (!kvm_vcpu_compatible(vcpu)) {
+ r = -EINVAL;
+ goto unlock_vcpu_destroy;
+ }
if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
r = -EINVAL;
goto unlock_vcpu_destroy;
Patches currently in stable-queue which might be from jslaby@xxxxxxx are
queue-3.0/kvm-x86-prevent-starting-pit-timers-in-the-absence-of-irqchip-support.patch
queue-3.0/kvm-x86-invalid-opcode-oops-on-set_sregs-with-osxsave-bit-set-cve-2012-4461.patch
queue-3.0/mm-hotplug-correctly-add-new-zone-to-all-other-nodes-zone-lists.patch
queue-3.0/macvtap-zerocopy-validate-vectors-before-building-skb.patch
queue-3.0/x25-validate-incoming-call-user-data-lengths.patch
queue-3.0/batman-adv-bat_socket_read-missing-checks.patch
queue-3.0/kvm-fix-buffer-overflow-in-kvm_set_irq.patch
queue-3.0/x25-handle-undersized-fragmented-skbs.patch
queue-3.0/nfsv4-include-bitmap-in-nfsv4-get-acl-data.patch
queue-3.0/nfs-nfs_getaclargs.acl_len-is-a-size_t.patch
queue-3.0/nfsv4-fix-an-oops-in-the-nfsv4-getacl-code.patch
queue-3.0/kvm-clean-up-error-handling-during-vcpu-creation.patch
queue-3.0/kvm-ensure-all-vcpus-are-consistent-with-in-kernel-irqchip-settings.patch
queue-3.0/batman-adv-only-write-requested-number-of-byte-to-user-buffer.patch
--
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