From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luca Boccassi Subject: [PATCH 2/2] virtio: fix PCI config err handling Date: Thu, 16 Aug 2018 19:47:50 +0100 Message-ID: <20180816184750.30843-2-bluca@debian.org> References: <20180814143035.19640-1-bluca@debian.org> <20180816184750.30843-1-bluca@debian.org> Cc: maxime.coquelin@redhat.com, zhihong.wang@intel.com, tiwei.bie@intel.com, bruce.richardson@intel.com, Brian Russell , Luca Boccassi To: dev@dpdk.org Return-path: Received: from mail-wm0-f65.google.com (mail-wm0-f65.google.com [74.125.82.65]) by dpdk.org (Postfix) with ESMTP id 0AB834C8E for ; Thu, 16 Aug 2018 20:47:59 +0200 (CEST) Received: by mail-wm0-f65.google.com with SMTP id l2-v6so16302452wme.1 for ; Thu, 16 Aug 2018 11:47:59 -0700 (PDT) In-Reply-To: <20180816184750.30843-1-bluca@debian.org> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" From: Brian Russell In virtio_read_caps and vtpci_msix_detect, rte_pci_read_config returns the number of bytes read from PCI config or < 0 on error. If less than the expected number of bytes are read then log the failure and return rather than carrying on with garbage. Fixes: 6ba1f63b5ab0 ("virtio: support specification 1.0") Signed-off-by: Brian Russell Signed-off-by: Luca Boccassi --- v2: handle additional rte_pci_read_config incomplete reads drivers/net/virtio/virtio_pci.c | 35 +++++++++++++++++++++------------ 1 file changed, 22 insertions(+), 13 deletions(-) diff --git a/drivers/net/virtio/virtio_pci.c b/drivers/net/virtio/virtio_pci.c index 6bd22e54a6..ff6f96f361 100644 --- a/drivers/net/virtio/virtio_pci.c +++ b/drivers/net/virtio/virtio_pci.c @@ -560,6 +560,7 @@ virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw) uint8_t pos; struct virtio_pci_cap cap; int ret; + uint32_t multiplier; if (rte_pci_map_device(dev)) { PMD_INIT_LOG(DEBUG, "failed to map pci device!"); @@ -567,16 +568,18 @@ virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw) } ret = rte_pci_read_config(dev, &pos, 1, PCI_CAPABILITY_LIST); - if (ret < 0) { - PMD_INIT_LOG(DEBUG, "failed to read pci capability list"); + if (ret != 1) { + PMD_INIT_LOG(DEBUG, + "failed to read pci capability list, ret %d", ret); return -1; } while (pos) { ret = rte_pci_read_config(dev, &cap, sizeof(cap), pos); - if (ret < 0) { - PMD_INIT_LOG(ERR, - "failed to read pci cap at pos: %x", pos); + if (ret != sizeof(cap)) { + PMD_INIT_LOG(DEBUG, + "failed to read pci cap at pos: %x ret %d", + pos, ret); break; } @@ -610,9 +613,13 @@ virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw) hw->common_cfg = get_cfg_addr(dev, &cap); break; case VIRTIO_PCI_CAP_NOTIFY_CFG: - rte_pci_read_config(dev, &hw->notify_off_multiplier, - 4, pos + sizeof(cap)); - hw->notify_base = get_cfg_addr(dev, &cap); + /* Avoid half-reads into hw */ + ret = rte_pci_read_config(dev, &multiplier, 4, + pos + sizeof(cap)); + if (ret == 4) { + hw->notify_off_multiplier = multiplier; + hw->notify_base = get_cfg_addr(dev, &cap); + } break; case VIRTIO_PCI_CAP_DEVICE_CFG: hw->dev_cfg = get_cfg_addr(dev, &cap); @@ -693,16 +700,18 @@ vtpci_msix_detect(struct rte_pci_device *dev) int ret; ret = rte_pci_read_config(dev, &pos, 1, PCI_CAPABILITY_LIST); - if (ret < 0) { - PMD_INIT_LOG(DEBUG, "failed to read pci capability list"); + if (ret != 1) { + PMD_INIT_LOG(DEBUG, + "failed to read pci capability list, ret %d", ret); return VIRTIO_MSIX_NONE; } while (pos) { ret = rte_pci_read_config(dev, &cap, sizeof(cap), pos); - if (ret < 0) { - PMD_INIT_LOG(ERR, - "failed to read pci cap at pos: %x", pos); + if (ret != sizeof(cap)) { + PMD_INIT_LOG(DEBUG, + "failed to read pci cap at pos: %x ret %d", + pos, ret); break; } -- 2.18.0