From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:33592 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729517AbfLENd0 (ORCPT ); Thu, 5 Dec 2019 08:33:26 -0500 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xB5DN7JV028748 for ; Thu, 5 Dec 2019 08:33:25 -0500 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0a-001b2d01.pphosted.com with ESMTP id 2wq1ky3v4b-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 05 Dec 2019 08:33:25 -0500 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 5 Dec 2019 13:33:23 -0000 From: Julian Wiedmann Subject: [PATCH net 1/3] s390/qeth: guard against runt packets Date: Thu, 5 Dec 2019 14:33:02 +0100 In-Reply-To: <20191205133304.58895-1-jwi@linux.ibm.com> References: <20191205133304.58895-1-jwi@linux.ibm.com> Message-Id: <20191205133304.58895-2-jwi@linux.ibm.com> Sender: linux-s390-owner@vger.kernel.org List-ID: To: David Miller Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, Heiko Carstens , Stefan Raspl , Ursula Braun , Julian Wiedmann Depending on a packet's type, the RX path needs to access fields in the packet headers and thus requires a minimum packet length. Enforce this length when building the skb. On the other hand a single runt packet is no reason to drop the whole RX buffer. So just skip it, and continue processing on the next packet. Fixes: 4a71df50047f ("qeth: new qeth device driver") Signed-off-by: Julian Wiedmann --- drivers/s390/net/qeth_core.h | 1 + drivers/s390/net/qeth_core_main.c | 27 +++++++++++++++++++++------ drivers/s390/net/qeth_ethtool.c | 1 + 3 files changed, 23 insertions(+), 6 deletions(-) diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index 293dd99b7fef..7cdebd2e329f 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -480,6 +480,7 @@ struct qeth_card_stats { u64 rx_dropped_nomem; u64 rx_dropped_notsupp; + u64 rx_dropped_runt; /* rtnl_link_stats64 */ u64 rx_packets; diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index efcbe60220d1..7285484212de 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -5063,9 +5063,9 @@ struct sk_buff *qeth_core_get_next_skb(struct qeth_card *card, { struct qdio_buffer_element *element = *__element; struct qdio_buffer *buffer = qethbuffer->buffer; + unsigned int headroom, linear_len; int offset = *__offset; bool use_rx_sg = false; - unsigned int headroom; struct sk_buff *skb; int skb_len = 0; void *data_ptr; @@ -5082,29 +5082,41 @@ struct sk_buff *qeth_core_get_next_skb(struct qeth_card *card, *hdr = element->addr + offset; offset += sizeof(struct qeth_hdr); + skb = NULL; + switch ((*hdr)->hdr.l2.id) { case QETH_HEADER_TYPE_LAYER2: skb_len = (*hdr)->hdr.l2.pkt_length; + linear_len = ETH_HLEN; headroom = 0; break; case QETH_HEADER_TYPE_LAYER3: skb_len = (*hdr)->hdr.l3.length; if (!IS_LAYER3(card)) { QETH_CARD_STAT_INC(card, rx_dropped_notsupp); - skb = NULL; goto walk_packet; } + if ((*hdr)->hdr.l3.flags & QETH_HDR_PASSTHRU) { + linear_len = ETH_HLEN; + headroom = 0; + break; + } + + if ((*hdr)->hdr.l3.flags & QETH_HDR_IPV6) + linear_len = sizeof(struct ipv6hdr); + else + linear_len = sizeof(struct iphdr); headroom = ETH_HLEN; break; case QETH_HEADER_TYPE_OSN: skb_len = (*hdr)->hdr.osn.pdu_length; if (!IS_OSN(card)) { QETH_CARD_STAT_INC(card, rx_dropped_notsupp); - skb = NULL; goto walk_packet; } + linear_len = skb_len; headroom = sizeof(struct qeth_hdr); break; default: @@ -5117,8 +5129,10 @@ struct sk_buff *qeth_core_get_next_skb(struct qeth_card *card, return NULL; } - if (!skb_len) - return NULL; + if (skb_len < linear_len) { + QETH_CARD_STAT_INC(card, rx_dropped_runt); + goto walk_packet; + } use_rx_sg = (card->options.cq == QETH_CQ_ENABLED) || ((skb_len >= card->options.rx_sg_cb) && @@ -6268,7 +6282,8 @@ void qeth_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) card->stats.rx_frame_errors + card->stats.rx_fifo_errors; stats->rx_dropped = card->stats.rx_dropped_nomem + - card->stats.rx_dropped_notsupp; + card->stats.rx_dropped_notsupp + + card->stats.rx_dropped_runt; stats->multicast = card->stats.rx_multicast; stats->rx_length_errors = card->stats.rx_length_errors; stats->rx_frame_errors = card->stats.rx_frame_errors; diff --git a/drivers/s390/net/qeth_ethtool.c b/drivers/s390/net/qeth_ethtool.c index f7485c6dea25..ab59bc975719 100644 --- a/drivers/s390/net/qeth_ethtool.c +++ b/drivers/s390/net/qeth_ethtool.c @@ -51,6 +51,7 @@ static const struct qeth_stats card_stats[] = { QETH_CARD_STAT("rx0 SG page allocs", rx_sg_alloc_page), QETH_CARD_STAT("rx0 dropped, no memory", rx_dropped_nomem), QETH_CARD_STAT("rx0 dropped, bad format", rx_dropped_notsupp), + QETH_CARD_STAT("rx0 dropped, runt", rx_dropped_runt), }; #define TXQ_STATS_LEN ARRAY_SIZE(txq_stats) -- 2.17.1