From 15466c4fe44344aad9086acef31a295e93a9917d Mon Sep 17 00:00:00 2001
From: Gal Pressman <galp@mellanox.com>
Date: Tue, 16 Jan 2018 15:41:59 +0200
Subject: [PATCH] ipaddress: Make sure VF min/max rate API is supported before
 using it

When using the new minimum rate API and providing only one parameter
(minimum rate/maximum rate), we query the VF min and max rate regardless
of kernel support.
This resulted in segmentation fault in ipaddr_loop_each_vf, which tries
to access NULL pointer.

This patch identifies such cases by testing the VF table for NULL
pointer in IFLA_VF_RATE, and aborts the operation.
Aborting on the first VF is valid since if the kernel does not support
the new API for the first VF, it will not support it for the other VFs
as well.

Fixes: f89a2a05ffa9 ("Add support to configure SR-IOV VF minimum and maximum Tx rate through ip tool")
Cc: Sucheta Chakraborty <sucheta.chakraborty@qlogic.com>
Signed-off-by: Gal Pressman <galp@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
(cherry picked from commit 39315157ab16205846ed34996cf4c8c0f58113c0)
Signed-off-by: Phil Sutter <psutter@redhat.com>
---
 ip/ipaddress.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/ip/ipaddress.c b/ip/ipaddress.c
index 9e9a7e0a6477f..bf27c15b4f718 100644
--- a/ip/ipaddress.c
+++ b/ip/ipaddress.c
@@ -2251,6 +2251,12 @@ ipaddr_loop_each_vf(struct rtattr *tb[], int vfnum, int *min, int *max)
 
 	for (i = RTA_DATA(vflist); RTA_OK(i, rem); i = RTA_NEXT(i, rem)) {
 		parse_rtattr_nested(vf, IFLA_VF_MAX, i);
+
+		if (!vf[IFLA_VF_RATE]) {
+			fprintf(stderr, "VF min/max rate API not supported\n");
+			exit(1);
+		}
+
 		vf_rate = RTA_DATA(vf[IFLA_VF_RATE]);
 		if (vf_rate->vf == vfnum) {
 			*min = vf_rate->min_tx_rate;
-- 
2.15.1