Now that memslots are torn down before kvm_arch_destroy_vm(), i.e. now that the massive, unaudited path that is known to have at least one rogue access to guest memory should be short-circuited before attempting to access user memory, WARN if KVM attempts to do a user access to guest memory with the wrong address space.
Signed-off-by: Sean Christopherson <[email protected]> --- include/linux/kvm_host.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index b37cf275ef79..2a88e4ce145e 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1352,7 +1352,7 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc, static __always_inline __must_check bool kvm_can_do_uaccess(struct kvm *kvm) { - return current->mm == kvm->mm; + return !WARN_ON_ONCE(current->mm != kvm->mm); } #define BUILD_KVM_COPY_USER_WRAPPER(fn, to_user, from_user) \ -- 2.56.0.rc1.315.gc6ed9934b7-goog
