summaryrefslogtreecommitdiff
path: root/virt
diff options
context:
space:
mode:
authorPei Li <peili.dev@gmail.com>2024-06-27 08:03:56 -0700
committerSean Christopherson <seanjc@google.com>2024-06-28 08:31:46 -0700
commitebbdf37ce9abb597015fa85df6630ebfa7d0a97f (patch)
tree03e311b026e64aa8a378e7d3b19e676ea7b17e0d /virt
parentdee67a94d4c6cbd05b8f6e1181498e94caa33334 (diff)
downloadlwn-ebbdf37ce9abb597015fa85df6630ebfa7d0a97f.tar.gz
lwn-ebbdf37ce9abb597015fa85df6630ebfa7d0a97f.zip
KVM: Validate hva in kvm_gpc_activate_hva() to fix __kvm_gpc_refresh() WARN
Check that the virtual address is "ok" when activating a gfn_to_pfn_cache with a host VA to ensure that KVM never attempts to use a bad address. This fixes a bug where KVM fails to check the incoming address when handling KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO_HVA in kvm_xen_vcpu_set_attr(). Reported-by: syzbot+fd555292a1da3180fc82@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=fd555292a1da3180fc82 Tested-by: syzbot+fd555292a1da3180fc82@syzkaller.appspotmail.com Signed-off-by: Pei Li <peili.dev@gmail.com> Reviewed-by: Paul Durrant <paul@xen.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20240627-bug5-v2-1-2c63f7ee6739@gmail.com [sean: rewrite changelog with --verbose] Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'virt')
-rw-r--r--virt/kvm/pfncache.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c
index e3453e869e92..f0039efb9e1e 100644
--- a/virt/kvm/pfncache.c
+++ b/virt/kvm/pfncache.c
@@ -430,6 +430,9 @@ int kvm_gpc_activate(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned long len)
int kvm_gpc_activate_hva(struct gfn_to_pfn_cache *gpc, unsigned long uhva, unsigned long len)
{
+ if (!access_ok((void __user *)uhva, len))
+ return -EINVAL;
+
return __kvm_gpc_activate(gpc, INVALID_GPA, uhva, len);
}