Subject: [PATCH 07/33] net/ipv6: don't return positive numbers when nothing was dumped

From: Jakub Kicinski <[email-masked]>
Date: Tue, 22 Jan 2019 14:47:19 -0800

[ Upstream commit 1518039f6b5ac794313c24c76f85cead0cd60f6c ]

in6_dump_addrs() returns a positive 1 if there was nothing to dump.
This return value can not be passed as return from inet6_dump_addr()
as is, because it will confuse rtnetlink, resulting in NLMSG_DONE
never getting set:

$ ip addr list dev lo
EOF on netlink
Dump terminated

v2: flip condition to avoid a new goto (DaveA)

Fixes: 7c1e8a3817c5 ("netlink: fixup regression in RTM_GETADDR")
Reported-by: Brendan Galloway <[email-masked]>
Signed-off-by: Jakub Kicinski <[email-masked]>
Reviewed-by: David Ahern <[email-masked]>
Tested-by: David Ahern <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 net/ipv6/addrconf.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index e3cb53b0ef67..d2b597674d60 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -5120,6 +5120,8 @@ static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
 			if (idev) {
 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
 						     &fillargs);
+				if (err > 0)
+					err = 0;
 			}
 			goto put_tgt_net;
 		}
-- 
2.20.1