Subject: [PATCH iproute2] ip rule: Require at least one argument for add

From: David Ahern <[email-masked]>
Date: Tue, 30 Oct 2018 13:59:05 -0700

From: David Ahern <[email-masked]>

'ip rule add' with no additional arguments just adds another rule
for the main table - which exists by default. Require at least
1 argument similar to delete.

Signed-off-by: David Ahern <[email-masked]>
---
 ip/iprule.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/ip/iprule.c b/ip/iprule.c
index d89d808d8909..b465a80785b1 100644
--- a/ip/iprule.c
+++ b/ip/iprule.c
@@ -691,6 +691,11 @@ static int iprule_modify(int cmd, int argc, char **argv)
 	};
 
 	if (cmd == RTM_NEWRULE) {
+		if (argc == 0) {
+			fprintf(stderr,
+				"\"ip rule add\" requires arguments.\n");
+			return -1;
+		}
 		req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL;
 		req.frh.action = FR_ACT_TO_TBL;
 	}
-- 
2.11.0