The following commit has been merged into the x86/seves branch of tip:
Commit-ID: e6eb15c9ba3165698488ae5c34920eea20eaa38e
Gitweb:
https://git.kernel.org/tip/e6eb15c9ba3165698488ae5c34920eea20eaa38e
Author: Vitaly Kuznetsov <vkuzn...@redhat.com>
AuthorDate: Mon, 14 Sep 2020 15:37:25 +02:00
Committer: Borislav Petkov <b...@suse.de>
CommitterDate: Mon, 14 Sep 2020 18:08:54 +02:00
KVM: nSVM: Avoid freeing uninitialized pointers in svm_set_nested_state()
The save and ctl pointers are passed uninitialized to kfree() when
svm_set_nested_state() follows the 'goto out_set_gif' path. While the
issue could've been fixed by initializing these on-stack varialbles to
NULL, it seems preferable to eliminate 'out_set_gif' label completely as
it is not actually a failure path and duplicating a single svm_set_gif()
call doesn't look too bad.
[ bp: Drop obscure Addresses-Coverity: tag. ]
Fixes: 6ccbd29ade0d ("KVM: SVM: nested: Don't allocate VMCB structures on
stack")
Reported-by: Dan Carpenter <dan.carpen...@oracle.com>
Reported-by: Joerg Roedel <jroe...@suse.de>
Reported-by: Colin King <colin.k...@canonical.com>
Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com>
Signed-off-by: Borislav Petkov <b...@suse.de>
Reviewed-by: Sean Christopherson <sean.j.christopher...@intel.com>
Acked-by: Joerg Roedel <jroe...@suse.de>
Tested-by: Tom Lendacky <thomas.lenda...@amd.com>
Link: https://lkml.kernel.org/r/20200914133725.650221-1-vkuzn...@redhat.com
---
arch/x86/kvm/svm/nested.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 2803662..d1ae94f 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1092,7 +1092,8 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
if (!(kvm_state->flags & KVM_STATE_NESTED_GUEST_MODE)) {
svm_leave_nested(svm);
- goto out_set_gif;
+ svm_set_gif(svm, !!(kvm_state->flags &
KVM_STATE_NESTED_GIF_SET));
+ return 0;
}
if (!page_address_valid(vcpu, kvm_state->hdr.svm.vmcb_pa))
@@ -1145,7 +1146,6 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu,
load_nested_vmcb_control(svm, ctl);
nested_prepare_vmcb_control(svm);
-out_set_gif:
svm_set_gif(svm, !!(kvm_state->flags & KVM_STATE_NESTED_GIF_SET));
ret = 0;
