Merge tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull 'struct fd' class updates from Al Viro:
 "The bulk of struct fd memory safety stuff

  Making sure that struct fd instances are destroyed in the same scope
  where they'd been created, getting rid of reassignments and passing
  them by reference, converting to CLASS(fd{,_pos,_raw}).

  We are getting very close to having the memory safety of that stuff
  trivial to verify"

* tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits)
  deal with the last remaing boolean uses of fd_file()
  css_set_fork(): switch to CLASS(fd_raw, ...)
  memcg_write_event_control(): switch to CLASS(fd)
  assorted variants of irqfd setup: convert to CLASS(fd)
  do_pollfd(): convert to CLASS(fd)
  convert do_select()
  convert vfs_dedupe_file_range().
  convert cifs_ioctl_copychunk()
  convert media_request_get_by_fd()
  convert spu_run(2)
  switch spufs_calls_{get,put}() to CLASS() use
  convert cachestat(2)
  convert do_preadv()/do_pwritev()
  fdget(), more trivial conversions
  fdget(), trivial conversions
  privcmd_ioeventfd_assign(): don't open-code eventfd_ctx_fdget()
  o2hb_region_dev_store(): avoid goto around fdget()/fdput()
  introduce "fd_pos" class, convert fdget_pos() users to it.
  fdget_raw() users: switch to CLASS(fd_raw)
  convert vmsplice() to CLASS(fd)
  ...

1 files changed, 13 insertions, 26 deletions

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index fb854cf20ac3..92d4711fd1e4 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -533,17 +533,12 @@ static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error)
 
 static int __sev_issue_cmd(int fd, int id, void *data, int *error)
 {
-	struct fd f;
-	int ret;
+	CLASS(fd, f)(fd);
 
-	f = fdget(fd);
-	if (!fd_file(f))
+	if (fd_empty(f))
 		return -EBADF;
 
-	ret = sev_issue_cmd_external_user(fd_file(f), id, data, error);
-
-	fdput(f);
-	return ret;
+	return sev_issue_cmd_external_user(fd_file(f), id, data, error);
 }
 
 static int sev_issue_cmd(struct kvm *kvm, int id, void *data, int *error)
@@ -2076,23 +2071,21 @@ int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd)
 {
 	struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info;
 	struct kvm_sev_info *src_sev, *cg_cleanup_sev;
-	struct fd f = fdget(source_fd);
+	CLASS(fd, f)(source_fd);
 	struct kvm *source_kvm;
 	bool charged = false;
 	int ret;
 
-	if (!fd_file(f))
+	if (fd_empty(f))
 		return -EBADF;
 
-	if (!file_is_kvm(fd_file(f))) {
-		ret = -EBADF;
-		goto out_fput;
-	}
+	if (!file_is_kvm(fd_file(f)))
+		return -EBADF;
 
 	source_kvm = fd_file(f)->private_data;
 	ret = sev_lock_two_vms(kvm, source_kvm);
 	if (ret)
-		goto out_fput;
+		return ret;
 
 	if (kvm->arch.vm_type != source_kvm->arch.vm_type ||
 	    sev_guest(kvm) || !sev_guest(source_kvm)) {
@@ -2139,8 +2132,6 @@ out_dst_cgroup:
 	cg_cleanup_sev->misc_cg = NULL;
 out_unlock:
 	sev_unlock_two_vms(kvm, source_kvm);
-out_fput:
-	fdput(f);
 	return ret;
 }
 
@@ -2801,23 +2792,21 @@ failed:
 
 int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd)
 {
-	struct fd f = fdget(source_fd);
+	CLASS(fd, f)(source_fd);
 	struct kvm *source_kvm;
 	struct kvm_sev_info *source_sev, *mirror_sev;
 	int ret;
 
-	if (!fd_file(f))
+	if (fd_empty(f))
 		return -EBADF;
 
-	if (!file_is_kvm(fd_file(f))) {
-		ret = -EBADF;
-		goto e_source_fput;
-	}
+	if (!file_is_kvm(fd_file(f)))
+		return -EBADF;
 
 	source_kvm = fd_file(f)->private_data;
 	ret = sev_lock_two_vms(kvm, source_kvm);
 	if (ret)
-		goto e_source_fput;
+		return ret;
 
 	/*
 	 * Mirrors of mirrors should work, but let's not get silly.  Also
@@ -2860,8 +2849,6 @@ int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd)
 
 e_unlock:
 	sev_unlock_two_vms(kvm, source_kvm);
-e_source_fput:
-	fdput(f);
 	return ret;
 }