Merge tag 'kernel-6.14-rc1.cred' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull cred refcount updates from Christian Brauner:
 "For the v6.13 cycle we switched overlayfs to a variant of
  override_creds() that doesn't take an extra reference. To this end the
  {override,revert}_creds_light() helpers were introduced.

  This generalizes the idea behind {override,revert}_creds_light() to
  the {override,revert}_creds() helpers. Afterwards overriding and
  reverting credentials is reference count free unless the caller
  explicitly takes a reference.

  All callers have been appropriately ported"

* tag 'kernel-6.14-rc1.cred' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (30 commits)
  cred: fold get_new_cred_many() into get_cred_many()
  cred: remove unused get_new_cred()
  nfsd: avoid pointless cred reference count bump
  cachefiles: avoid pointless cred reference count bump
  dns_resolver: avoid pointless cred reference count bump
  trace: avoid pointless cred reference count bump
  cgroup: avoid pointless cred reference count bump
  acct: avoid pointless reference count bump
  io_uring: avoid pointless cred reference count bump
  smb: avoid pointless cred reference count bump
  cifs: avoid pointless cred reference count bump
  cifs: avoid pointless cred reference count bump
  ovl: avoid pointless cred reference count bump
  open: avoid pointless cred reference count bump
  nfsfh: avoid pointless cred reference count bump
  nfs/nfs4recover: avoid pointless cred reference count bump
  nfs/nfs4idmap: avoid pointless reference count bump
  nfs/localio: avoid pointless cred reference count bumps
  coredump: avoid pointless cred reference count bump
  binfmt_misc: avoid pointless cred reference count bump
  ...

4 files changed, 3 insertions, 6 deletions

diff --git a/fs/nfsd/auth.c b/fs/nfsd/auth.c
index 93e33d1ee891..4dc327e02456 100644
--- a/fs/nfsd/auth.c
+++ b/fs/nfsd/auth.c
@@ -27,7 +27,7 @@ int nfsd_setuser(struct svc_cred *cred, struct svc_export *exp)
 	int flags = nfsexp_flags(cred, exp);
 
 	/* discard any old override before preparing the new set */
-	revert_creds(get_cred(current_real_cred()));
+	put_cred(revert_creds(get_cred(current_real_cred())));
 	new = prepare_creds();
 	if (!new)
 		return -ENOMEM;
@@ -80,7 +80,6 @@ int nfsd_setuser(struct svc_cred *cred, struct svc_export *exp)
 		new->cap_effective = cap_raise_nfsd_set(new->cap_effective,
 							new->cap_permitted);
 	put_cred(override_creds(new));
-	put_cred(new);
 	return 0;
 
 oom:
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index a1cdba42c4fa..dc5c9d8e8202 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -1248,7 +1248,7 @@ nfsd_file_acquire_local(struct net *net, struct svc_cred *cred,
 
 	beres = nfsd_file_do_acquire(NULL, net, cred, client,
 				     fhp, may_flags, NULL, pnf, true);
-	revert_creds(save_cred);
+	put_cred(revert_creds(save_cred));
 	return beres;
 }
 
diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c
index 4a765555bf84..7f2ceeb118a4 100644
--- a/fs/nfsd/nfs4recover.c
+++ b/fs/nfsd/nfs4recover.c
@@ -82,14 +82,13 @@ nfs4_save_creds(const struct cred **original_creds)
 	new->fsuid = GLOBAL_ROOT_UID;
 	new->fsgid = GLOBAL_ROOT_GID;
 	*original_creds = override_creds(new);
-	put_cred(new);
 	return 0;
 }
 
 static void
 nfs4_reset_creds(const struct cred *original)
 {
-	revert_creds(original);
+	put_cred(revert_creds(original));
 }
 
 static void
diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index 6a831cb242df..98d6459724a7 100644
--- a/fs/nfsd/nfsfh.c
+++ b/fs/nfsd/nfsfh.c
@@ -222,7 +222,6 @@ static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct net *net,
 			cap_raise_nfsd_set(new->cap_effective,
 					   new->cap_permitted);
 		put_cred(override_creds(new));
-		put_cred(new);
 	} else {
 		error = nfsd_setuser_and_check_port(rqstp, cred, exp);
 		if (error)