From: Sean Christopherson Date: Sat, 11 Jan 2025 00:20:20 +0000 (-0800) Subject: KVM: Add a dedicated API for setting KVM-internal memslots X-Git-Tag: v6.14-rc1~94^2~9^2~2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=156bffdb2b49fc0c869bf160a57378886f5fa92d;p=thirdparty%2Fkernel%2Flinux.git KVM: Add a dedicated API for setting KVM-internal memslots Add a dedicated API for setting internal memslots, and have it explicitly disallow setting userspace memslots. Setting a userspace memslots without a direct command from userspace would result in all manner of issues. No functional change intended. Cc: Tao Su Cc: Claudio Imbrenda Cc: Christian Borntraeger Reviewed-by: Xiaoyao Li Reviewed-by: Claudio Imbrenda Acked-by: Christoph Schlameuss Link: https://lore.kernel.org/r/20250111002022.1230573-4-seanjc@google.com Signed-off-by: Sean Christopherson --- diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a861287a67bd4..36b5d06e39045 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -12827,7 +12827,7 @@ void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, m.guest_phys_addr = gpa; m.userspace_addr = hva; m.memory_size = size; - r = __kvm_set_memory_region(kvm, &m); + r = kvm_set_internal_memslot(kvm, &m); if (r < 0) return ERR_PTR_USR(r); } diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 7443de24b1d98..8707d25a2e5ba 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1192,8 +1192,8 @@ enum kvm_mr_change { KVM_MR_FLAGS_ONLY, }; -int __kvm_set_memory_region(struct kvm *kvm, - const struct kvm_userspace_memory_region2 *mem); +int kvm_set_internal_memslot(struct kvm *kvm, + const struct kvm_userspace_memory_region2 *mem); void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot); void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen); int kvm_arch_prepare_memory_region(struct kvm *kvm, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 7d25b50cb298a..e1be2e4e6c9f0 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1926,8 +1926,8 @@ static bool kvm_check_memslot_overlap(struct kvm_memslots *slots, int id, return false; } -int __kvm_set_memory_region(struct kvm *kvm, - const struct kvm_userspace_memory_region2 *mem) +static int __kvm_set_memory_region(struct kvm *kvm, + const struct kvm_userspace_memory_region2 *mem) { struct kvm_memory_slot *old, *new; struct kvm_memslots *slots; @@ -2050,7 +2050,16 @@ out: kfree(new); return r; } -EXPORT_SYMBOL_GPL(__kvm_set_memory_region); + +int kvm_set_internal_memslot(struct kvm *kvm, + const struct kvm_userspace_memory_region2 *mem) +{ + if (WARN_ON_ONCE(mem->slot < KVM_USER_MEM_SLOTS)) + return -EINVAL; + + return __kvm_set_memory_region(kvm, mem); +} +EXPORT_SYMBOL_GPL(kvm_set_internal_memslot); static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm, struct kvm_userspace_memory_region2 *mem)