Patch "KVM: MMU: handle invalid root_hpa at __direct_map" has been added to the 3.13-stable tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This is a note to let you know that I've just added the patch titled

    KVM: MMU: handle invalid root_hpa at __direct_map

to the 3.13-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-mmu-handle-invalid-root_hpa-at-__direct_map.patch
and it can be found in the queue-3.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From 989c6b34f6a9480e397b170cc62237e89bf4fdb9 Mon Sep 17 00:00:00 2001
From: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Date: Thu, 19 Dec 2013 15:28:51 -0200
Subject: KVM: MMU: handle invalid root_hpa at __direct_map

From: Marcelo Tosatti <mtosatti@xxxxxxxxxx>

commit 989c6b34f6a9480e397b170cc62237e89bf4fdb9 upstream.

It is possible for __direct_map to be called on invalid root_hpa
(-1), two examples:

1) try_async_pf -> can_do_async_pf
    -> vmx_interrupt_allowed -> nested_vmx_vmexit
2) vmx_handle_exit -> vmx_interrupt_allowed -> nested_vmx_vmexit

Then to load_vmcs12_host_state and kvm_mmu_reset_context.

Check for this possibility, let fault exception be regenerated.

BZ: https://bugzilla.redhat.com/show_bug.cgi?id=924916

Signed-off-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Josh Boyer <jwboyer@xxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/x86/kvm/mmu.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2659,6 +2659,9 @@ static int __direct_map(struct kvm_vcpu
 	int emulate = 0;
 	gfn_t pseudo_gfn;
 
+	if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
+		return 0;
+
 	for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) {
 		if (iterator.level == level) {
 			mmu_set_spte(vcpu, iterator.sptep, ACC_ALL,


Patches currently in stable-queue which might be from mtosatti@xxxxxxxxxx are

queue-3.13/kvm-vmx-fix-use-after-free-of-vmx-loaded_vmcs.patch
queue-3.13/kvm-mmu-handle-invalid-root_hpa-at-__direct_map.patch
queue-3.13/kvm-x86-handle-invalid-root_hpa-everywhere.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]