From f999b1962a34f97cec52c3adff81d79890697a7f Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Wed, 6 Aug 2014 16:17:58 +0200 Subject: [PATCH] KVM: s390: Fix user triggerable bug in dead code 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 Reviewed-by: Cornelia Huck Reviewed-by: David Hildenbrand [lizf: Backported to 3.4: - adjust context - no KVM_EXIT_S390_TSCH and KVM_EXIT_DEBUG in 3.4] Signed-off-by: Zefan Li --- arch/s390/kvm/kvm-s390.c | 11 ----------- 1 file changed, 11 deletions(-) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 53c973ebc0c8f..0f250d12a18cb 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -566,17 +566,6 @@ rerun_vcpu: BUG_ON(vcpu->kvm->arch.float_int.local_int[vcpu->vcpu_id] == NULL); - 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: - 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) { -- 2.47.2