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charset="UTF-8" X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 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 --- 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 be27b4e8f12d..f3f59bdf7e18 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1355,7 +1355,7 @@ 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) \ -- 2.56.0.307.g5fe7bd680c-goog