From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Jan Stancek" , "Veaceslav Falico" , "Eric Dumazet" , "Daniel Borkmann" , "Phil Sutter" , "David S. Miller" , "Willem de Bruijn" Date: Sun, 29 Dec 2013 03:08:44 +0100 Message-ID: Subject: [PATCH 3.2 168/185] af_packet: block BH in prb_shutdown_retire_blk_timer() In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.2.54-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Veaceslav Falico [ 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" CC: Daniel Borkmann CC: Willem de Bruijn CC: Phil Sutter CC: Eric Dumazet Reported-by: Jan Stancek Tested-by: Jan Stancek Signed-off-by: Veaceslav Falico Acked-by: Daniel Borkmann Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/packet/af_packet.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 7616c58..4f19bf2 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -505,9 +505,9 @@ static void prb_shutdown_retire_blk_timer(struct packet_sock *po, 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); }