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* re: [SCSI] cxgb3i: convert cdev->l2opt to use rcu to prevent NULL dereference (v2)
@ 2011-09-26 13:40 Dan Carpenter
  2011-09-26 14:20 ` Neil Horman
  0 siblings, 1 reply; 4+ messages in thread
From: Dan Carpenter @ 2011-09-26 13:40 UTC (permalink / raw)
  To: nhorman; +Cc: netdev, linux-scsi

Hi Neil,

c98bc57ee65b6 "[SCSI] cxgb3i: convert cdev->l2opt to use rcu to
prevent NULL dereference (v2)" from linux-next introduces a usinging
uninitialized variable bug.

 struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
                             struct net_device *dev)
 {
-       struct l2t_entry *e;
-       struct l2t_data *d = L2DATA(cdev);
+       struct l2t_entry *e = NULL;
+       struct l2t_data *d;
        u32 addr = *(u32 *) neigh->primary_key;
        int ifidx = neigh->dev->ifindex;
        int hash = arp_hash(addr, ifidx, d);
                                         ^
Uninitialized variable.

        struct port_info *p = netdev_priv(dev);
        int smt_idx = p->port_id;
 
+       rcu_read_lock();
+       d = L2DATA(cdev);
+       if (!d)
+               goto done_rcu;
+

regards,
dan carpenter

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [SCSI] cxgb3i: convert cdev->l2opt to use rcu to prevent NULL dereference (v2)
  2011-09-26 13:40 [SCSI] cxgb3i: convert cdev->l2opt to use rcu to prevent NULL dereference (v2) Dan Carpenter
@ 2011-09-26 14:20 ` Neil Horman
  2011-09-26 14:31   ` James Bottomley
  0 siblings, 1 reply; 4+ messages in thread
From: Neil Horman @ 2011-09-26 14:20 UTC (permalink / raw)
  To: Dan Carpenter; +Cc: netdev, linux-scsi

On Mon, Sep 26, 2011 at 04:40:48PM +0300, Dan Carpenter wrote:
> Hi Neil,
> 
> c98bc57ee65b6 "[SCSI] cxgb3i: convert cdev->l2opt to use rcu to
> prevent NULL dereference (v2)" from linux-next introduces a usinging
> uninitialized variable bug.
> 
>  struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
>                              struct net_device *dev)
>  {
> -       struct l2t_entry *e;
> -       struct l2t_data *d = L2DATA(cdev);
> +       struct l2t_entry *e = NULL;
> +       struct l2t_data *d;
>         u32 addr = *(u32 *) neigh->primary_key;
>         int ifidx = neigh->dev->ifindex;
>         int hash = arp_hash(addr, ifidx, d);
>                                          ^
> Uninitialized variable.
> 
>         struct port_info *p = netdev_priv(dev);
>         int smt_idx = p->port_id;
>  
> +       rcu_read_lock();
> +       d = L2DATA(cdev);
> +       if (!d)
> +               goto done_rcu;
> +
> 
> regards,
> dan carpenter
> 

Yup, thanks, you need this to9 fix the uninitalized var.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

 l2t.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)


diff --git a/drivers/net/cxgb3/l2t.c b/drivers/net/cxgb3/l2t.c
index 3808f99..4154097 100644
--- a/drivers/net/cxgb3/l2t.c
+++ b/drivers/net/cxgb3/l2t.c
@@ -302,9 +302,9 @@ struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
 {
 	struct l2t_entry *e = NULL;
 	struct l2t_data *d;
+	int hash;
 	u32 addr = *(u32 *) neigh->primary_key;
 	int ifidx = neigh->dev->ifindex;
-	int hash = arp_hash(addr, ifidx, d);
 	struct port_info *p = netdev_priv(dev);
 	int smt_idx = p->port_id;
 
@@ -313,6 +313,8 @@ struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
 	if (!d)
 		goto done_rcu;
 
+	hash = arp_hash(addr, ifidx, d);
+
 	write_lock_bh(&d->lock);
 	for (e = d->l2tab[hash].first; e; e = e->next)
 		if (e->addr == addr && e->ifindex == ifidx &&

^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [SCSI] cxgb3i: convert cdev->l2opt to use rcu to prevent NULL dereference (v2)
  2011-09-26 14:20 ` Neil Horman
@ 2011-09-26 14:31   ` James Bottomley
  2011-09-26 15:02     ` Neil Horman
  0 siblings, 1 reply; 4+ messages in thread
From: James Bottomley @ 2011-09-26 14:31 UTC (permalink / raw)
  To: Neil Horman; +Cc: Dan Carpenter, netdev, linux-scsi

On Mon, 2011-09-26 at 10:20 -0400, Neil Horman wrote:
> On Mon, Sep 26, 2011 at 04:40:48PM +0300, Dan Carpenter wrote:
> > Hi Neil,
> > 
> > c98bc57ee65b6 "[SCSI] cxgb3i: convert cdev->l2opt to use rcu to
> > prevent NULL dereference (v2)" from linux-next introduces a usinging
> > uninitialized variable bug.
> > 
> >  struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
> >                              struct net_device *dev)
> >  {
> > -       struct l2t_entry *e;
> > -       struct l2t_data *d = L2DATA(cdev);
> > +       struct l2t_entry *e = NULL;
> > +       struct l2t_data *d;
> >         u32 addr = *(u32 *) neigh->primary_key;
> >         int ifidx = neigh->dev->ifindex;
> >         int hash = arp_hash(addr, ifidx, d);
> >                                          ^
> > Uninitialized variable.
> > 
> >         struct port_info *p = netdev_priv(dev);
> >         int smt_idx = p->port_id;
> >  
> > +       rcu_read_lock();
> > +       d = L2DATA(cdev);
> > +       if (!d)
> > +               goto done_rcu;
> > +
> > 
> > regards,
> > dan carpenter
> > 
> 
> Yup, thanks, you need this to9 fix the uninitalized var.

I rolled this into the original.

James



^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [SCSI] cxgb3i: convert cdev->l2opt to use rcu to prevent NULL dereference (v2)
  2011-09-26 14:31   ` James Bottomley
@ 2011-09-26 15:02     ` Neil Horman
  0 siblings, 0 replies; 4+ messages in thread
From: Neil Horman @ 2011-09-26 15:02 UTC (permalink / raw)
  To: James Bottomley; +Cc: Dan Carpenter, netdev, linux-scsi

On Mon, Sep 26, 2011 at 09:31:15AM -0500, James Bottomley wrote:
> On Mon, 2011-09-26 at 10:20 -0400, Neil Horman wrote:
> > On Mon, Sep 26, 2011 at 04:40:48PM +0300, Dan Carpenter wrote:
> > > Hi Neil,
> > > 
> > > c98bc57ee65b6 "[SCSI] cxgb3i: convert cdev->l2opt to use rcu to
> > > prevent NULL dereference (v2)" from linux-next introduces a usinging
> > > uninitialized variable bug.
> > > 
> > >  struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
> > >                              struct net_device *dev)
> > >  {
> > > -       struct l2t_entry *e;
> > > -       struct l2t_data *d = L2DATA(cdev);
> > > +       struct l2t_entry *e = NULL;
> > > +       struct l2t_data *d;
> > >         u32 addr = *(u32 *) neigh->primary_key;
> > >         int ifidx = neigh->dev->ifindex;
> > >         int hash = arp_hash(addr, ifidx, d);
> > >                                          ^
> > > Uninitialized variable.
> > > 
> > >         struct port_info *p = netdev_priv(dev);
> > >         int smt_idx = p->port_id;
> > >  
> > > +       rcu_read_lock();
> > > +       d = L2DATA(cdev);
> > > +       if (!d)
> > > +               goto done_rcu;
> > > +
> > > 
> > > regards,
> > > dan carpenter
> > > 
> > 
> > Yup, thanks, you need this to9 fix the uninitalized var.
> 
> I rolled this into the original.
> 
Thank you!
Neil

> James
> 
> 
> 

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2011-09-26 15:02 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-09-26 13:40 [SCSI] cxgb3i: convert cdev->l2opt to use rcu to prevent NULL dereference (v2) Dan Carpenter
2011-09-26 14:20 ` Neil Horman
2011-09-26 14:31   ` James Bottomley
2011-09-26 15:02     ` Neil Horman

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