From 5eb70dbebf32c2fd1f2814c654ae17fc47d6e859 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Tue, 17 Dec 2024 18:25:08 -0800 Subject: [PATCH] netdev-genl: avoid empty messages in queue dump Empty netlink responses from do() are not correct (as opposed to dump() where not dumping anything is perfectly fine). We should return an error if the target object does not exist, in this case if the netdev is down it has no queues. Fixes: 6b6171db7fc8 ("netdev-genl: Add netlink framework functions for queue") Reported-by: syzbot+0a884bc2d304ce4af70f@syzkaller.appspotmail.com Reviewed-by: Eric Dumazet Reviewed-by: Joe Damato Link: https://patch.msgid.link/20241218022508.815344-1-kuba@kernel.org Signed-off-by: Jakub Kicinski --- net/core/netdev-genl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c index 1be8c7c21d19..2d3ae0cd3ad2 100644 --- a/net/core/netdev-genl.c +++ b/net/core/netdev-genl.c @@ -430,10 +430,10 @@ static int netdev_nl_queue_fill(struct sk_buff *rsp, struct net_device *netdev, u32 q_idx, u32 q_type, const struct genl_info *info) { - int err = 0; + int err; if (!(netdev->flags & IFF_UP)) - return err; + return -ENOENT; err = netdev_nl_queue_validate(netdev, q_idx, q_type); if (err) -- 2.25.1