[dpdk-stable] patch 'net/virtio: fix PCI config error handling' has been queued to stable release 18.08.1

[Kevin Traynor]

Hi,

FYI, your patch has been queued to stable release 18.08.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/29/18. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the patch applied
to the branch. If the code is different (ie: not only metadata diffs), due for example to
a change in context or macro names, please double check it.

Thanks.

Kevin Traynor

---
>From e0af7542c97f172f44d633389d33920b889e8b22 Mon Sep 17 00:00:00 2001
From: Brian Russell <brussell at brocade.com>
Date: Tue, 28 Aug 2018 11:12:40 +0100
Subject: [PATCH] net/virtio: fix PCI config error handling

[ upstream commit 49bb1f7a0ab760a0f1fb39e27c90a1cb2ad42edd ]

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 <brussell at brocade.com>
Signed-off-by: Luca Boccassi <bluca at debian.org>
Reviewed-by: Tiwei Bie <tiwei.bie at intel.com>
---
 drivers/net/virtio/virtio_pci.c | 65 ++++++++++++++++++++++++---------
 1 file changed, 48 insertions(+), 17 deletions(-)

diff --git a/drivers/net/virtio/virtio_pci.c b/drivers/net/virtio/virtio_pci.c
index 6bd22e54a..b6a3c80b4 100644
--- a/drivers/net/virtio/virtio_pci.c
+++ b/drivers/net/virtio/virtio_pci.c
@@ -568,14 +568,16 @@ 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);
+		ret = rte_pci_read_config(dev, &cap, 2, pos);
+		if (ret != 2) {
+			PMD_INIT_LOG(DEBUG,
+				     "failed to read pci cap at pos: %x ret %d",
+				     pos, ret);
 			break;
 		}
@@ -587,5 +589,14 @@ virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw)
 			 * cap; next two bytes are the flags.
 			 */
-			uint16_t flags = ((uint16_t *)&cap)[1];
+			uint16_t flags;
+
+			ret = rte_pci_read_config(dev, &flags, sizeof(flags),
+					pos + 2);
+			if (ret != sizeof(flags)) {
+				PMD_INIT_LOG(DEBUG,
+					     "failed to read pci cap at pos:"
+					     " %x ret %d", pos + 2, ret);
+				break;
+			}
 
 			if (flags & PCI_MSIX_ENABLE)
@@ -602,4 +613,12 @@ virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw)
 		}
 
+		ret = rte_pci_read_config(dev, &cap, sizeof(cap), pos);
+		if (ret != sizeof(cap)) {
+			PMD_INIT_LOG(DEBUG,
+				     "failed to read pci cap at pos: %x ret %d",
+				     pos, ret);
+			break;
+		}
+
 		PMD_INIT_LOG(DEBUG,
 			"[%2x] cfg type: %u, bar: %u, offset: %04x, len: %u",
@@ -690,23 +709,35 @@ vtpci_msix_detect(struct rte_pci_device *dev)
 {
 	uint8_t pos;
-	struct virtio_pci_cap cap;
 	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);
+		uint8_t cap[2];
+
+		ret = rte_pci_read_config(dev, cap, sizeof(cap), pos);
+		if (ret != sizeof(cap)) {
+			PMD_INIT_LOG(DEBUG,
+				     "failed to read pci cap at pos: %x ret %d",
+				     pos, ret);
 			break;
 		}
 
-		if (cap.cap_vndr == PCI_CAP_ID_MSIX) {
-			uint16_t flags = ((uint16_t *)&cap)[1];
+		if (cap[0] == PCI_CAP_ID_MSIX) {
+			uint16_t flags;
+
+			ret = rte_pci_read_config(dev, &flags, sizeof(flags),
+					pos + sizeof(cap));
+			if (ret != sizeof(flags)) {
+				PMD_INIT_LOG(DEBUG,
+					     "failed to read pci cap at pos:"
+					     " %x ret %d", pos + 2, ret);
+				break;
+			}
 
 			if (flags & PCI_MSIX_ENABLE)
@@ -716,5 +747,5 @@ vtpci_msix_detect(struct rte_pci_device *dev)
 		}
 
-		pos = cap.cap_next;
+		pos = cap[1];
 	}
 
-- 
2.19.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2018-11-23 10:22:54.406494254 +0000
+++ 0006-net-virtio-fix-PCI-config-error-handling.patch	2018-11-23 10:22:54.000000000 +0000
@@ -1,15 +1,16 @@
-From 49bb1f7a0ab760a0f1fb39e27c90a1cb2ad42edd Mon Sep 17 00:00:00 2001
+From e0af7542c97f172f44d633389d33920b889e8b22 Mon Sep 17 00:00:00 2001
 From: Brian Russell <brussell at brocade.com>
 Date: Tue, 28 Aug 2018 11:12:40 +0100
 Subject: [PATCH] net/virtio: fix PCI config error handling
 
+[ upstream commit 49bb1f7a0ab760a0f1fb39e27c90a1cb2ad42edd ]
+
 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")
-Cc: stable at dpdk.org
 
 Signed-off-by: Brian Russell <brussell at brocade.com>
 Signed-off-by: Luca Boccassi <bluca at debian.org>