On Thu, Jun 02, 2022 at 11:41:32AM -0700, Andrew Morton wrote:
> On Wed, 1 Jun 2022 17:56:22 -0700 Roman Gushchin <roman.gushchin@xxxxxxxxx> wrote:
>
> > >
> > > > + ssize_t ret;
> > > > +
> > > > + if (copy_from_user(kbuf, buf, read_len))
> > > > + return -EFAULT;
> > > > + kbuf[read_len] = '\0';
> > > > +
> > > > + if (sscanf(kbuf, "%lu %d %lu", &ino, &nid, &nr_to_scan) < 2)
> > >
> > > Was it intentional to permit more than three args?
> >
> > Good catch! No, of course it wasn't intentional.
> >
> > Below is an updated version of this patch.
> >
> > ...
> >
> > + if (sscanf(kbuf, "%lu %d %lu", &ino, &nid, &nr_to_scan) != 2)
> > + return -EINVAL;
>
> s/2/3/methinks?
>
>
My bad, of course. Thanks!
--
diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c
index 12026472daae..e5b40c43221d 100644
--- a/mm/shrinker_debug.c
+++ b/mm/shrinker_debug.c
@@ -124,7 +124,7 @@ static ssize_t shrinker_debugfs_scan_write(struct file *file,
return -EFAULT;
kbuf[read_len] = '\0';
- if (sscanf(kbuf, "%lu %d %lu", &ino, &nid, &nr_to_scan) != 2)
+ if (sscanf(kbuf, "%lu %d %lu", &ino, &nid, &nr_to_scan) != 3)
return -EINVAL;
if (nid < 0 || nid >= nr_node_ids)
