diff options
author | Suravee Suthikulpanit | 2020-02-21 08:52:17 -0600 |
---|---|---|
committer | Paolo Bonzini | 2020-02-21 18:05:20 +0100 |
commit | 93fd9666c269877fffb74e14f52792d9c000c1f2 (patch) | |
tree | 68a7a46d160caff8e75015b48e57b2d40bb2dc01 | |
parent | 624e18f92f2ec449c2b3a6d388c0dccc45e4c4d7 (diff) |
kvm: x86: svm: Fix NULL pointer dereference when AVIC not enabled
Launching VM w/ AVIC disabled together with pass-through device
results in NULL pointer dereference bug with the following call trace.
RIP: 0010:svm_refresh_apicv_exec_ctrl+0x17e/0x1a0 [kvm_amd]
Call Trace:
kvm_vcpu_update_apicv+0x44/0x60 [kvm]
kvm_arch_vcpu_ioctl_run+0x3f4/0x1c80 [kvm]
kvm_vcpu_ioctl+0x3d8/0x650 [kvm]
do_vfs_ioctl+0xaa/0x660
? tomoyo_file_ioctl+0x19/0x20
ksys_ioctl+0x67/0x90
__x64_sys_ioctl+0x1a/0x20
do_syscall_64+0x57/0x190
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Investigation shows that this is due to the uninitialized usage of
struct vapu_svm.ir_list in the svm_set_pi_irte_mode(), which is
called from svm_refresh_apicv_exec_ctrl().
The ir_list is initialized only if AVIC is enabled. So, fixes by
adding a check if AVIC is enabled in the svm_refresh_apicv_exec_ctrl().
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206579
Fixes: 8937d762396d ("kvm: x86: svm: Add support to (de)activate posted interrupts.")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-rw-r--r-- | arch/x86/kvm/svm.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index bef0ba35f121..a391b29138f0 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -5232,6 +5232,9 @@ static void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu) struct vmcb *vmcb = svm->vmcb; bool activated = kvm_vcpu_apicv_active(vcpu); + if (!avic) + return; + if (activated) { /** * During AVIC temporary deactivation, guest could update |