mirror of
https://github.com/Fishwaldo/Star64_linux.git
synced 2025-03-16 04:04:06 +00:00
KVM: avoid NULL pointer dereference in kvm_dirty_ring_push
commit 5593473a1e
upstream.
kvm_vcpu_release() will call kvm_dirty_ring_free(), freeing
ring->dirty_gfns and setting it to NULL. Afterwards, it calls
kvm_arch_vcpu_destroy().
However, if closing the file descriptor races with KVM_RUN in such away
that vcpu->arch.st.preempted == 0, the following call stack leads to a
NULL pointer dereference in kvm_dirty_run_push():
mark_page_dirty_in_slot+0x192/0x270 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3171
kvm_steal_time_set_preempted arch/x86/kvm/x86.c:4600 [inline]
kvm_arch_vcpu_put+0x34e/0x5b0 arch/x86/kvm/x86.c:4618
vcpu_put+0x1b/0x70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:211
vmx_free_vcpu+0xcb/0x130 arch/x86/kvm/vmx/vmx.c:6985
kvm_arch_vcpu_destroy+0x76/0x290 arch/x86/kvm/x86.c:11219
kvm_vcpu_destroy arch/x86/kvm/../../../virt/kvm/kvm_main.c:441 [inline]
The fix is to release the dirty page ring after kvm_arch_vcpu_destroy
has run.
Reported-by: Qiuhao Li <qiuhao@sysec.org>
Reported-by: Gaoning Pan <pgn@zju.edu.cn>
Reported-by: Yongkang Jia <kangel@zju.edu.cn>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
e0b4a80cff
commit
58e5e54d94
1 changed files with 1 additions and 1 deletions
|
@ -431,8 +431,8 @@ static void kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
|
|||
|
||||
void kvm_vcpu_destroy(struct kvm_vcpu *vcpu)
|
||||
{
|
||||
kvm_dirty_ring_free(&vcpu->dirty_ring);
|
||||
kvm_arch_vcpu_destroy(vcpu);
|
||||
kvm_dirty_ring_free(&vcpu->dirty_ring);
|
||||
|
||||
/*
|
||||
* No need for rcu_read_lock as VCPU_RUN is the only place that changes
|
||||
|
|
Loading…
Add table
Reference in a new issue