'vector' and 'trig_mode' fields of 'struct kvm_lapic_irq' are left
uninitialized in kvm_pv_kick_cpu_op(). While these fields are normally
not needed for APIC_DM_REMRD, they're still referenced by
__apic_accept_irq() for trace_kvm_apic_accept_irq(). Fully initialize
the structure to avoid consuming random stack memory.
Fixes:
a183b638b61c ("KVM: x86: make apic_accept_irq tracepoint more generic")
Reported-by: syzbot+d6caa905917d353f0d07@syzkaller.appspotmail.com
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <
20220708125147.593975-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
*/
static void kvm_pv_kick_cpu_op(struct kvm *kvm, int apicid)
{
*/
static void kvm_pv_kick_cpu_op(struct kvm *kvm, int apicid)
{
- struct kvm_lapic_irq lapic_irq;
-
- lapic_irq.shorthand = APIC_DEST_NOSHORT;
- lapic_irq.dest_mode = APIC_DEST_PHYSICAL;
- lapic_irq.level = 0;
- lapic_irq.dest_id = apicid;
- lapic_irq.msi_redir_hint = false;
+ /*
+ * All other fields are unused for APIC_DM_REMRD, but may be consumed by
+ * common code, e.g. for tracing. Defer initialization to the compiler.
+ */
+ struct kvm_lapic_irq lapic_irq = {
+ .delivery_mode = APIC_DM_REMRD,
+ .dest_mode = APIC_DEST_PHYSICAL,
+ .shorthand = APIC_DEST_NOSHORT,
+ .dest_id = apicid,
+ };
- lapic_irq.delivery_mode = APIC_DM_REMRD;
kvm_irq_delivery_to_apic(kvm, NULL, &lapic_irq, NULL);
}
kvm_irq_delivery_to_apic(kvm, NULL, &lapic_irq, NULL);
}