sev-dev: avoid pointless cred reference count bump

and fix a memory leak while at it. The new creds are created via
prepare_creds() and then reverted via put_cred(revert_creds()). The
additional reference count bump from override_creds() wasn't even taken
into account before.

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Jeff Layton <[email protected]>
Reviewed-by: Jens Axboe <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

Author: brauner

drivers/crypto/ccp/sev-dev.c

@@ -244,7 +244,7 @@ static struct file *open_file_as_root(const char *filename, int flags, umode_t m
 	if (!cred)
 		return ERR_PTR(-ENOMEM);
 	cred->fsuid = GLOBAL_ROOT_UID;
-	old_cred = override_creds(get_new_cred(cred));
+	old_cred = override_creds(cred);
 
 	fp = file_open_root(&root, filename, flags, mode);
 	path_put(&root);