namei: saner calling conventions for filename_create()

a) make it reject ERR_PTR() for name
b) make it putname(name) upon return in all other cases.

seriously simplifies the callers...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 10 insertions, 16 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 593cf3b01e74..628b6eb9415f 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3403,6 +3403,8 @@ static struct dentry *filename_create(int dfd, struct filename *name,
         int error;
         bool is_dir = (lookup_flags & LOOKUP_DIRECTORY);
 
+        if (IS_ERR(name))
+                return ERR_CAST(name);
         /*
          * Note that only LOOKUP_REVAL and LOOKUP_DIRECTORY matter here. Any
          * other flags passed in are ignored!
@@ -3410,8 +3412,10 @@ static struct dentry *filename_create(int dfd, struct filename *name,
         lookup_flags &= LOOKUP_REVAL;
 
         error = filename_parentat(dfd, name, lookup_flags, path, &last, &type);
-        if (error)
+        if (error) {
+                putname(name);
                 return ERR_PTR(error);
+        }
 
         /*
          * Yucky last component or no last component at all?
@@ -3449,6 +3453,7 @@ static struct dentry *filename_create(int dfd, struct filename *name,
                 error = err2;
                 goto fail;
         }
+        putname(name);
         return dentry;
 fail:
         dput(dentry);
@@ -3459,20 +3464,15 @@ unlock:
                 mnt_drop_write(path->mnt);
 out:
         path_put(path);
+        putname(name);
         return dentry;
 }
 
 struct dentry *kern_path_create(int dfd, const char *pathname,
                                 struct path *path, unsigned int lookup_flags)
 {
-        struct filename *filename = getname_kernel(pathname);
-        struct dentry *res;
-
-        if (IS_ERR(filename))
-                return ERR_CAST(filename);
-        res = filename_create(dfd, filename, path, lookup_flags);
-        putname(filename);
-        return res;
+        return filename_create(dfd, getname_kernel(pathname),
+                                path, lookup_flags);
 }
 EXPORT_SYMBOL(kern_path_create);
 
@@ -3488,13 +3488,7 @@ EXPORT_SYMBOL(done_path_create);
 struct dentry *user_path_create(int dfd, const char __user *pathname,
                                 struct path *path, unsigned int lookup_flags)
 {
-        struct filename *tmp = getname(pathname);
-        struct dentry *res;
-        if (IS_ERR(tmp))
-                return ERR_CAST(tmp);
-        res = filename_create(dfd, tmp, path, lookup_flags);
-        putname(tmp);
-        return res;
+        return filename_create(dfd, getname(pathname), path, lookup_flags);
 }
 EXPORT_SYMBOL(user_path_create);