[dpdk-stable] patch 'net/failsafe: fix parameters parsing' has been queued to stable release 17.08.1

[Yuanhan Liu]

Hi,

FYI, your patch has been queued to stable release 17.08.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/24/17. So please
shout if anyone has objections.

Thanks.

	--yliu

---
>From 3d2115da7360fc0cae912a745c266b2d0d691dbb Mon Sep 17 00:00:00 2001
From: Matan Azrad <matan at mellanox.com>
Date: Sun, 27 Aug 2017 10:23:14 +0300
Subject: [PATCH] net/failsafe: fix parameters parsing

[ upstream commit 852be6520b0384a47bbf4f45fe62df01e165cf53 ]

The corrupted code used wrongly snprintf return value as the
number of characters actually copied, in spite of the meaning
is the number of characters which would be generated for the
given input.

It caused to remain zerod bytes between the failsafe command line
non sub device parameters indicates end of string.

Hence, when rte_kvargs_parse tried to parse all parameters, it
got end of string after the first one and the others weren't parsed.

So, if the mac parameters was the first in command line it was
taken while hotplug_poll was left default, and vice versa.

The fix updates the buffer index by dedicated variable contains
the copy size, by the way validates the comma separation.

Fixes: a46f8d584eb8 ("net/failsafe: add fail-safe PMD")

Signed-off-by: Matan Azrad <matan at mellanox.com>
Acked-by: Gaetan Rivet <gaetan.rivet at 6wind.com>
---
 drivers/net/failsafe/failsafe_args.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/net/failsafe/failsafe_args.c b/drivers/net/failsafe/failsafe_args.c
index 1f22416..ae857b0 100644
--- a/drivers/net/failsafe/failsafe_args.c
+++ b/drivers/net/failsafe/failsafe_args.c
@@ -286,10 +286,17 @@ fs_remove_sub_devices_definition(char params[DEVARGS_MAXLEN])
 			ERROR("Invalid parameter");
 			return -EINVAL;
 		}
-		if (params[b] == ',' || params[b] == '\0')
-			i += snprintf(&buffer[i], b - a + 1, "%s", &params[a]);
-		if (params[b] == '(') {
+		if (params[b] == ',' || params[b] == '\0') {
+			size_t len = b - a;
+
+			if (i > 0)
+				len += 1;
+			snprintf(&buffer[i], len + 1, "%s%s",
+					i ? "," : "", &params[a]);
+			i += len;
+		} else if (params[b] == '(') {
 			size_t start = b;
+
 			b += closing_paren(&params[b]);
 			if (b == start)
 				return -EINVAL;
@@ -393,6 +400,7 @@ failsafe_args_parse(struct rte_eth_dev *dev, const char *params)
 					&dev->data->mac_addrs[0]);
 			if (ret < 0)
 				goto free_kvlist;
+
 			mac_from_arg = 1;
 		}
 	}
-- 
2.7.4