Re: [PATCH] 9pfs: simplify v9fs_walk()

[Christian Schoenebeck]

On Montag, 17. Mai 2021 13:35:09 CEST Greg Kurz wrote:
> On Sun, 16 May 2021 17:55:34 +0200
> 
> Christian Schoenebeck <qemu_oss@crudebyte.com> wrote:
> > There is only one comparison between nwnames and P9_MAXWELEM required.
> > 
> > Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
> > ---
> 
> Nice catch. It's been there for a decade :)
> 
> Reviewed-by: Greg Kurz <groug@kaod.org>

Now that was a quick response! Queued, thanks!

https://github.com/cschoenebeck/qemu/commits/9p.next

> 
> >  hw/9pfs/9p.c | 9 +++++----
> >  1 file changed, 5 insertions(+), 4 deletions(-)
> > 
> > diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
> > index 0fa776af09..89aa07db78 100644
> > --- a/hw/9pfs/9p.c
> > +++ b/hw/9pfs/9p.c
> > @@ -1739,7 +1739,11 @@ static void coroutine_fn v9fs_walk(void *opaque)
> > 
> >      trace_v9fs_walk(pdu->tag, pdu->id, fid, newfid, nwnames);
> > 
> > -    if (nwnames && nwnames <= P9_MAXWELEM) {
> > +    if (nwnames > P9_MAXWELEM) {
> > +        err = -EINVAL;
> > +        goto out_nofid;
> > +    }
> > +    if (nwnames) {
> > 
> >          wnames = g_new0(V9fsString, nwnames);
> >          qids   = g_new0(V9fsQID, nwnames);
> >          for (i = 0; i < nwnames; i++) {
> > 
> > @@ -1753,9 +1757,6 @@ static void coroutine_fn v9fs_walk(void *opaque)
> > 
> >              }
> >              offset += err;
> >          
> >          }
> > 
> > -    } else if (nwnames > P9_MAXWELEM) {
> > -        err = -EINVAL;
> > -        goto out_nofid;
> > 
> >      }
> >      fidp = get_fid(pdu, fid);
> >      if (fidp == NULL) {