OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

KVM: s390: avoid memory overwrites on emergency signal injection 

Commit 383d0b0501 ("KVM: s390: handle pending local interrupts via
bitmap") introduced a possible memory overwrite from user space.

User space could pass an invalid emergency signal code (sending VCPU)
and therefore exceed the bitmap. Let's take care of this case and
check that the id is in the valid range.

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v3.19+ db27a7a KVM: Provide function for VCPU lookup by id
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
David Hildenbrand 2015-11-05 09:38:15 +01:00 committed by Christian Borntraeger
parent db27a7a37a
commit b85de33a1a
1 changed files with 4 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/s390/kvm/interrupt.c
View File

@ -1110,6 +1110,10 @@ static int __inject_sigp_emergency(struct kvm_vcpu *vcpu,
trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_INT_EMERGENCY,
irq->u.emerg.code, 0);
/* sending vcpu invalid */
if (kvm_get_vcpu_by_id(vcpu->kvm, irq->u.emerg.code) == NULL)
return -EINVAL;
set_bit(irq->u.emerg.code, li->sigp_emerg_pending);
set_bit(IRQ_PEND_EXT_EMERGENCY, &li->pending_irqs);
atomic_or(CPUSTAT_EXT_INT, li->cpuflags);