From patchwork Tue Aug 2 14:41:21 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sagi Grimberg X-Patchwork-Id: 15101 X-Patchwork-Delegate: bruce.richardson@intel.com Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [IPv6:::1]) by dpdk.org (Postfix) with ESMTP id 545443977; Tue, 2 Aug 2016 16:41:26 +0200 (CEST) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by dpdk.org (Postfix) with ESMTP id 14E5E3772 for ; Tue, 2 Aug 2016 16:41:25 +0200 (CEST) Received: from bzq-82-81-101-184.red.bezeqint.net ([82.81.101.184] helo=bombadil.infradead.org) by merlin.infradead.org with esmtpsa (Exim 4.85_2 #1 (Red Hat Linux)) id 1bUasm-0008OR-24; Tue, 02 Aug 2016 14:41:24 +0000 From: Sagi Grimberg To: dev@dpdk.org Cc: Adrien Mazarguil Date: Tue, 2 Aug 2016 17:41:21 +0300 Message-Id: <1470148881-24115-1-git-send-email-sagi@grimberg.me> X-Mailer: git-send-email 1.9.1 Subject: [dpdk-dev] [PATCH v3] net/mlx5: fix possible NULL deref in Rx path X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" The user is allowed to call ->rx_pkt_burst() even without free mbufs in the pool. In this scenario we'll fail allocating a rep mbuf on the first iteration (where pkt is still NULL). This would cause us to deref a NULL pkt (reset refcount and free). Fix this by checking the pkt before freeing it. Fixes: a1bdb71a32da ("net/mlx5: fix crash in Rx") Signed-off-by: Sagi Grimberg Acked-by: Adrien Mazarguil --- Changes from v2: - fix check-git-log.sh complaints - collected acked-by tag Changes from v1: - check pkt only once in case we failed to allocate a buffer drivers/net/mlx5/mlx5_rxtx.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c index fce3381ae87a..37573668e43e 100644 --- a/drivers/net/mlx5/mlx5_rxtx.c +++ b/drivers/net/mlx5/mlx5_rxtx.c @@ -1572,6 +1572,14 @@ mlx5_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n) rte_prefetch0(wqe); rep = rte_mbuf_raw_alloc(rxq->mp); if (unlikely(rep == NULL)) { + ++rxq->stats.rx_nombuf; + if (!pkt) { + /* + * no buffers before we even started, + * bail out silently. + */ + break; + } while (pkt != seg) { assert(pkt != (*rxq->elts)[idx]); seg = NEXT(pkt); @@ -1579,7 +1587,6 @@ mlx5_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n) __rte_mbuf_raw_free(pkt); pkt = seg; } - ++rxq->stats.rx_nombuf; break; } if (!pkt) {