From: Vlad Buslov <vladbu@mellanox.com>
Date: Mon, 4 Jun 2018 18:32:23 +0300
Subject: net: sched: return error code when tcf proto is not found
Patch-mainline: v4.18-rc1
Git-commit: 0e3990356d2518691e17c1ecbf7868833b6e6704
References: bsc#1109837

If requested tcf proto is not found, get and del filter netlink protocol
handlers output error message to extack, but do not return actual error
code. Add check to return ENOENT when result of tp find function is NULL
pointer.

Fixes: c431f89b18a2 ("net: sched: split tc_ctl_tfilter into three handlers")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/sched/cls_api.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -1274,7 +1274,7 @@ static int tc_del_tfilter(struct sk_buff
 			       prio, false);
 	if (!tp || IS_ERR(tp)) {
 		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
-		err = PTR_ERR(tp);
+		err = tp ? PTR_ERR(tp) : -ENOENT;
 		goto errout;
 	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
 		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
@@ -1374,7 +1374,7 @@ static int tc_get_tfilter(struct sk_buff
 			       prio, false);
 	if (!tp || IS_ERR(tp)) {
 		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
-		err = PTR_ERR(tp);
+		err = tp ? PTR_ERR(tp) : -ENOENT;
 		goto errout;
 	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
 		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");