This is a note to let you know that I've just added the patch titled KVM: s390: fix wrong lookup of VCPUs by array index to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: kvm-s390-fix-wrong-lookup-of-vcpus-by-array-index.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 152e9f65d66f0a3891efc3869440becc0e7ff53f Mon Sep 17 00:00:00 2001 From: David Hildenbrand <dahi@xxxxxxxxxxxxxxxxxx> Date: Thu, 5 Nov 2015 09:06:06 +0100 Subject: KVM: s390: fix wrong lookup of VCPUs by array index From: David Hildenbrand <dahi@xxxxxxxxxxxxxxxxxx> commit 152e9f65d66f0a3891efc3869440becc0e7ff53f upstream. For now, VCPUs were always created sequentially with incrementing VCPU ids. Therefore, the index in the VCPUs array matched the id. As sequential creation might change with cpu hotplug, let's use the correct lookup function to find a VCPU by id, not array index. Let's also use kvm_lookup_vcpu() for validation of the sending VCPU on external call injection. Reviewed-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> Signed-off-by: David Hildenbrand <dahi@xxxxxxxxxxxxxxxxxx> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/kvm/interrupt.c | 3 +-- arch/s390/kvm/sigp.c | 8 ++------ 2 files changed, 3 insertions(+), 8 deletions(-) --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -1054,8 +1054,7 @@ static int __inject_extcall(struct kvm_v src_id, 0, 2); /* sending vcpu invalid */ - if (src_id >= KVM_MAX_VCPUS || - kvm_get_vcpu(vcpu->kvm, src_id) == NULL) + if (kvm_get_vcpu_by_id(vcpu->kvm, src_id) == NULL) return -EINVAL; if (sclp_has_sigpif()) --- a/arch/s390/kvm/sigp.c +++ b/arch/s390/kvm/sigp.c @@ -294,12 +294,8 @@ static int handle_sigp_dst(struct kvm_vc u16 cpu_addr, u32 parameter, u64 *status_reg) { int rc; - struct kvm_vcpu *dst_vcpu; + struct kvm_vcpu *dst_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr); - if (cpu_addr >= KVM_MAX_VCPUS) - return SIGP_CC_NOT_OPERATIONAL; - - dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr); if (!dst_vcpu) return SIGP_CC_NOT_OPERATIONAL; @@ -481,7 +477,7 @@ int kvm_s390_handle_sigp_pei(struct kvm_ trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr); if (order_code == SIGP_EXTERNAL_CALL) { - dest_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr); + dest_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr); BUG_ON(dest_vcpu == NULL); kvm_s390_vcpu_wakeup(dest_vcpu); Patches currently in stable-queue which might be from dahi@xxxxxxxxxxxxxxxxxx are queue-4.1/kvm-s390-sca-must-not-cross-page-boundaries.patch queue-4.1/kvm-s390-fix-wrong-lookup-of-vcpus-by-array-index.patch queue-4.1/kvm-s390-avoid-memory-overwrites-on-emergency-signal-injection.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html