KVM: s390: avoid memory leaks if __inject_vm() fails

We have to delete the allocated interrupt info if __inject_vm() fails.

Otherwise user space can keep flooding kvm with floating interrupts and
provoke more and more memory leaks.

Reported-by: Dominik Dingel <[email protected]>
Reviewed-by: Dominik Dingel <[email protected]>
Signed-off-by: David Hildenbrand <[email protected]>
Cc: [email protected] # v3.15+
Signed-off-by: Christian Borntraeger <[email protected]>

diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index a6cb238049d18fa92f40be7f6b51ae4b143df257..6d7513e1556082f5f860ef9ebe8cdbe875d5db17 100644 (file)
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -1277,6 +1277,7 @@ int kvm_s390_inject_vm(struct kvm *kvm,
                       struct kvm_s390_interrupt *s390int)
 {
        struct kvm_s390_interrupt_info *inti;
+       int rc;
 
        inti = kzalloc(sizeof(*inti), GFP_KERNEL);
        if (!inti)
@@ -1324,7 +1325,10 @@ int kvm_s390_inject_vm(struct kvm *kvm,
        trace_kvm_s390_inject_vm(s390int->type, s390int->parm, s390int->parm64,
                                 2);
 
-       return __inject_vm(kvm, inti);
+       rc = __inject_vm(kvm, inti);
+       if (rc)
+               kfree(inti);
+       return rc;
 }
 
 void kvm_s390_reinject_io_int(struct kvm *kvm,