nfs: use credential guards in nfs_idmap_get_key()

Use credential guards for scoped credential override with automatic
restoration on scope exit.

Link: https://patch.msgid.link/20251103-work-creds-guards-simple-v1-12-a3e156839e7f@kernel.org
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/nfs/nfs4idmap.c b/fs/nfs/nfs4idmap.c
index 00932500fce42e9bf90af743c74e6a15c74fbb33..9e1c48c5c0b8a69cbce0337c692b0557020d7230 100644 (file)
--- a/fs/nfs/nfs4idmap.c
+++ b/fs/nfs/nfs4idmap.c
@@ -306,15 +306,12 @@ static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
                                 const char *type, void *data,
                                 size_t data_size, struct idmap *idmap)
 {
-       const struct cred *saved_cred;
        struct key *rkey;
        const struct user_key_payload *payload;
        ssize_t ret;
 
-       saved_cred = override_creds(id_resolver_cache);
-       rkey = nfs_idmap_request_key(name, namelen, type, idmap);
-       revert_creds(saved_cred);
-
+       scoped_with_creds(id_resolver_cache)
+               rkey = nfs_idmap_request_key(name, namelen, type, idmap);
        if (IS_ERR(rkey)) {
                ret = PTR_ERR(rkey);
                goto out;