From: David Ahern <dsahern@gmail.com>
Date: Thu, 3 Jan 2019 02:26:13 +0000 (-0800)
Subject: ipv6: Fix dump of specific table with strict checking
X-Git-Tag: v5.4.17~4453^2~1
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=73155879b3c1ac3ace35208a54a3a160ec520bef;p=arm%2Flinux.git

ipv6: Fix dump of specific table with strict checking

Dump of a specific table with strict checking enabled is looping. The
problem is that the end of the table dump is not marked in the cb. When
dumping a specific table, cb args 0 and 1 are not used (they are the hash
index and entry with an hash table index when dumping all tables). Re-use
args[0] to hold a 'done' flag for the specific table dump.

Fixes: 13e38901d46ca ("net/ipv6: Plumb support for filtering route dumps")
Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index ae3786132c23..6613d8dbb0e5 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -627,7 +627,11 @@ static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
 			return -ENOENT;
 		}
 
-		res = fib6_dump_table(tb, skb, cb);
+		if (!cb->args[0]) {
+			res = fib6_dump_table(tb, skb, cb);
+			if (!res)
+				cb->args[0] = 1;
+		}
 		goto out;
 	}