| Message ID | 1443432762-5561-1-git-send-email-lynxis@fe80.eu |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
Acked-by: James Chapman <jchapman@katalix.com> On 28 September 2015 at 10:32, Alexander Couzens <lynxis@fe80.eu> wrote: > There is a small chance that tunnel_free() is called before tunnel->del_work scheduled > resulting in a zero pointer dereference. > > Signed-off-by: Alexander Couzens <lynxis@fe80.eu> > --- > net/l2tp/l2tp_core.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c > index f6b090d..afca2eb 100644 > --- a/net/l2tp/l2tp_core.c > +++ b/net/l2tp/l2tp_core.c > @@ -1319,7 +1319,7 @@ static void l2tp_tunnel_del_work(struct work_struct *work) > tunnel = container_of(work, struct l2tp_tunnel, del_work); > sk = l2tp_tunnel_sock_lookup(tunnel); > if (!sk) > - return; > + goto out; > > sock = sk->sk_socket; > > @@ -1341,6 +1341,8 @@ static void l2tp_tunnel_del_work(struct work_struct *work) > } > > l2tp_tunnel_sock_put(sk); > +out: > + l2tp_tunnel_dec_refcount(tunnel); > } > > /* Create a socket for the tunnel, if one isn't set up by > @@ -1636,8 +1638,13 @@ EXPORT_SYMBOL_GPL(l2tp_tunnel_create); > */ > int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel) > { > + l2tp_tunnel_inc_refcount(tunnel); > l2tp_tunnel_closeall(tunnel); > - return (false == queue_work(l2tp_wq, &tunnel->del_work)); > + if (false == queue_work(l2tp_wq, &tunnel->del_work)) { > + l2tp_tunnel_dec_refcount(tunnel); > + return 1; > + } > + return 0; > } > EXPORT_SYMBOL_GPL(l2tp_tunnel_delete); > > -- > 2.5.3 > > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Alexander Couzens <lynxis@fe80.eu> Date: Mon, 28 Sep 2015 11:32:42 +0200 > There is a small chance that tunnel_free() is called before tunnel->del_work scheduled > resulting in a zero pointer dereference. > > Signed-off-by: Alexander Couzens <lynxis@fe80.eu> Applied and queued up for -stable, thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index f6b090d..afca2eb 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -1319,7 +1319,7 @@ static void l2tp_tunnel_del_work(struct work_struct *work) tunnel = container_of(work, struct l2tp_tunnel, del_work); sk = l2tp_tunnel_sock_lookup(tunnel); if (!sk) - return; + goto out; sock = sk->sk_socket; @@ -1341,6 +1341,8 @@ static void l2tp_tunnel_del_work(struct work_struct *work) } l2tp_tunnel_sock_put(sk); +out: + l2tp_tunnel_dec_refcount(tunnel); } /* Create a socket for the tunnel, if one isn't set up by @@ -1636,8 +1638,13 @@ EXPORT_SYMBOL_GPL(l2tp_tunnel_create); */ int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel) { + l2tp_tunnel_inc_refcount(tunnel); l2tp_tunnel_closeall(tunnel); - return (false == queue_work(l2tp_wq, &tunnel->del_work)); + if (false == queue_work(l2tp_wq, &tunnel->del_work)) { + l2tp_tunnel_dec_refcount(tunnel); + return 1; + } + return 0; } EXPORT_SYMBOL_GPL(l2tp_tunnel_delete);
There is a small chance that tunnel_free() is called before tunnel->del_work scheduled resulting in a zero pointer dereference. Signed-off-by: Alexander Couzens <lynxis@fe80.eu> --- net/l2tp/l2tp_core.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)