| From 1f25ea537dcb2c3d42b7c0989b2dc31fa21c87da Mon Sep 17 00:00:00 2001 |
| From: Veaceslav Falico <vfalico@redhat.com> |
| Date: Fri, 29 Nov 2013 09:53:23 +0100 |
| Subject: af_packet: block BH in prb_shutdown_retire_blk_timer() |
| |
| From: Veaceslav Falico <vfalico@redhat.com> |
| |
| [ Upstream commit ec6f809ff6f19fafba3212f6aff0dda71dfac8e8 ] |
| |
| Currently we're using plain spin_lock() in prb_shutdown_retire_blk_timer(), |
| however the timer might fire right in the middle and thus try to re-aquire |
| the same spinlock, leaving us in a endless loop. |
| |
| To fix that, use the spin_lock_bh() to block it. |
| |
| Fixes: f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation.") |
| CC: "David S. Miller" <davem@davemloft.net> |
| CC: Daniel Borkmann <dborkman@redhat.com> |
| CC: Willem de Bruijn <willemb@google.com> |
| CC: Phil Sutter <phil@nwl.cc> |
| CC: Eric Dumazet <edumazet@google.com> |
| Reported-by: Jan Stancek <jstancek@redhat.com> |
| Tested-by: Jan Stancek <jstancek@redhat.com> |
| Signed-off-by: Veaceslav Falico <vfalico@redhat.com> |
| Acked-by: Daniel Borkmann <dborkman@redhat.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/packet/af_packet.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/net/packet/af_packet.c |
| +++ b/net/packet/af_packet.c |
| @@ -439,9 +439,9 @@ static void prb_shutdown_retire_blk_time |
| |
| pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc; |
| |
| - spin_lock(&rb_queue->lock); |
| + spin_lock_bh(&rb_queue->lock); |
| pkc->delete_blk_timer = 1; |
| - spin_unlock(&rb_queue->lock); |
| + spin_unlock_bh(&rb_queue->lock); |
| |
| prb_del_retire_blk_timer(pkc); |
| } |