[dpdk-stable] patch 'bus/pci: fix TOCTOU for sysfs access' has been queued to LTS release 18.11.3

[Kevin Traynor]

Hi,

FYI, your patch has been queued to LTS release 18.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 06/27/19. 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. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/kevintraynor/dpdk-stable-queue

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable-queue/commit/8f54619deab26614e850adbf8a60d33f7c5b4736

Thanks.

Kevin Traynor

---
>From 8f54619deab26614e850adbf8a60d33f7c5b4736 Mon Sep 17 00:00:00 2001
From: Stephen Hemminger <stephen at networkplumber.org>
Date: Tue, 2 Apr 2019 11:51:05 -0700
Subject: [PATCH] bus/pci: fix TOCTOU for sysfs access

[ upstream commit c530aa78e3747cdd273310eeb9c50603da7f9cb6 ]

Using access followed by open causes a static analysis warning
about Time of check versus Time of use. Also, access() and
open() have different UID permission checks.

This is not a serious problem; but easy to fix by using errno instead.

Coverity issue: 300870
Fixes: 4a928ef9f611 ("bus/pci: enable write combining during mapping")

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
Reviewed-by: David Marchand <david.marchand at redhat.com>
---
 drivers/bus/pci/linux/pci_uio.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/bus/pci/linux/pci_uio.c b/drivers/bus/pci/linux/pci_uio.c
index 09ecbb7aa..0d1b9aa34 100644
--- a/drivers/bus/pci/linux/pci_uio.c
+++ b/drivers/bus/pci/linux/pci_uio.c
@@ -315,10 +315,9 @@ pci_uio_map_resource_by_index(struct rte_pci_device *dev, int res_idx,
 			loc->function, res_idx);
 
-		if (access(devname, R_OK|W_OK) != -1) {
-			fd = open(devname, O_RDWR);
-			if (fd < 0)
-				RTE_LOG(INFO, EAL, "%s cannot be mapped. "
-					"Fall-back to non prefetchable mode.\n",
-					devname);
+		fd = open(devname, O_RDWR);
+		if (fd < 0 && errno != ENOENT) {
+			RTE_LOG(INFO, EAL, "%s cannot be mapped. "
+				"Fall-back to non prefetchable mode.\n",
+				devname);
 		}
 	}
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2019-06-24 16:18:57.257645187 +0100
+++ 0042-bus-pci-fix-TOCTOU-for-sysfs-access.patch	2019-06-24 16:18:55.086429925 +0100
@@ -1 +1 @@
-From c530aa78e3747cdd273310eeb9c50603da7f9cb6 Mon Sep 17 00:00:00 2001
+From 8f54619deab26614e850adbf8a60d33f7c5b4736 Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit c530aa78e3747cdd273310eeb9c50603da7f9cb6 ]
+
@@ -14 +15,0 @@
-Cc: stable at dpdk.org
@@ -23 +24 @@
-index 65f4896b9..f240fe4f2 100644
+index 09ecbb7aa..0d1b9aa34 100644
@@ -26 +27 @@
-@@ -316,10 +316,9 @@ pci_uio_map_resource_by_index(struct rte_pci_device *dev, int res_idx,
+@@ -315,10 +315,9 @@ pci_uio_map_resource_by_index(struct rte_pci_device *dev, int res_idx,