| From | Greg Kroah-Hartman <> | Subject | [PATCH 3.16 209/357] KVM: s390: Fix user triggerable bug in dead code | Date | Fri, 3 Oct 2014 14:29:55 -0700 |
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3.16-stable review patch. If anyone has any objections, please let me know.
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From: Christian Borntraeger <borntraeger@de.ibm.com>
commit 614a80e474b227cace52fd6e3c790554db8a396e upstream.
In the early days, we had some special handling for the KVM_EXIT_S390_SIEIC exit, but this was gone in 2009 with commit d7b0b5eb3000 (KVM: s390: Make psw available on all exits, not just a subset).
Now this switch statement is just a sanity check for userspace not messing with the kvm_run structure. Unfortunately, this allows userspace to trigger a kernel BUG. Let's just remove this switch statement.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- arch/s390/kvm/kvm-s390.c | 13 ------------- 1 file changed, 13 deletions(-)
--- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -1286,19 +1286,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_v kvm_s390_vcpu_start(vcpu); - switch (kvm_run->exit_reason) { - case KVM_EXIT_S390_SIEIC: - case KVM_EXIT_UNKNOWN: - case KVM_EXIT_INTR: - case KVM_EXIT_S390_RESET: - case KVM_EXIT_S390_UCONTROL: - case KVM_EXIT_S390_TSCH: - case KVM_EXIT_DEBUG: - break; - default: - BUG(); - } - vcpu->arch.sie_block->gpsw.mask = kvm_run->psw_mask; vcpu->arch.sie_block->gpsw.addr = kvm_run->psw_addr; if (kvm_run->kvm_dirty_regs & KVM_SYNC_PREFIX) {
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