vfs: turn do_path_lookup into wrapper around struct filename variant
...and make the user_path callers use that variant instead.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index 5dbc3f83..8c14353 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1988,18 +1988,28 @@
return err;
}
+static int filename_lookup(int dfd, struct filename *name,
+ unsigned int flags, struct nameidata *nd)
+{
+ int retval = path_lookupat(dfd, name->name, flags | LOOKUP_RCU, nd);
+ if (unlikely(retval == -ECHILD))
+ retval = path_lookupat(dfd, name->name, flags, nd);
+ if (unlikely(retval == -ESTALE))
+ retval = path_lookupat(dfd, name->name,
+ flags | LOOKUP_REVAL, nd);
+
+ if (likely(!retval))
+ audit_inode(name->name, nd->path.dentry,
+ flags & LOOKUP_PARENT);
+ return retval;
+}
+
static int do_path_lookup(int dfd, const char *name,
unsigned int flags, struct nameidata *nd)
{
- int retval = path_lookupat(dfd, name, flags | LOOKUP_RCU, nd);
- if (unlikely(retval == -ECHILD))
- retval = path_lookupat(dfd, name, flags, nd);
- if (unlikely(retval == -ESTALE))
- retval = path_lookupat(dfd, name, flags | LOOKUP_REVAL, nd);
+ struct filename filename = { .name = name };
- if (likely(!retval))
- audit_inode(name, nd->path.dentry, flags & LOOKUP_PARENT);
- return retval;
+ return filename_lookup(dfd, &filename, flags, nd);
}
/* does lookup, returns the object with parent locked */
@@ -2125,7 +2135,7 @@
BUG_ON(flags & LOOKUP_PARENT);
- err = do_path_lookup(dfd, tmp->name, flags, &nd);
+ err = filename_lookup(dfd, tmp, flags, &nd);
putname(tmp);
if (!err)
*path = nd.path;
@@ -2139,6 +2149,12 @@
return user_path_at_empty(dfd, name, flags, path, NULL);
}
+/*
+ * NB: most callers don't do anything directly with the reference to the
+ * to struct filename, but the nd->last pointer points into the name string
+ * allocated by getname. So we must hold the reference to it until all
+ * path-walking is complete.
+ */
static struct filename *
user_path_parent(int dfd, const char __user *path, struct nameidata *nd)
{
@@ -2148,7 +2164,7 @@
if (IS_ERR(s))
return s;
- error = do_path_lookup(dfd, s->name, LOOKUP_PARENT, nd);
+ error = filename_lookup(dfd, s, LOOKUP_PARENT, nd);
if (error) {
putname(s);
return ERR_PTR(error);