[PATCH net] mctp: Fix incorrect netdev unref for extended addr
From: Matt Johnston <matt@codeconstruct.com.au>
Date: 2022-02-18 05:22:12
Subsystem:
management component transport protocol (mctp), networking [general], the rest · Maintainers:
Jeremy Kerr, Matt Johnston, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
In the extended addressing local route output codepath
dev_get_by_index_rcu() doesn't take a dev_hold() so we shouldn't
dev_put(). Instead we need to hold/put the mctp_dev.
Fixes: 2a98db59117e ("mctp: Implement extended addressing")
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
---
net/mctp/route.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/net/mctp/route.c b/net/mctp/route.c
index e52cef750500..6ef79ab4a076 100644
--- a/net/mctp/route.c
+++ b/net/mctp/route.c@@ -786,9 +786,8 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, { struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk); struct mctp_skb_cb *cb = mctp_cb(skb); - struct mctp_route tmp_rt; + struct mctp_route tmp_rt = {0}; struct mctp_sk_key *key; - struct net_device *dev; struct mctp_hdr *hdr; unsigned long flags; unsigned int mtu;
@@ -801,12 +800,12 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, if (rt) { ext_rt = false; - dev = NULL; - if (WARN_ON(!rt->dev)) goto out_release; } else if (cb->ifindex) { + struct net_device *dev; + ext_rt = true; rt = &tmp_rt;
@@ -816,8 +815,9 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, rcu_read_unlock(); return rc; } - rt->dev = __mctp_dev_get(dev); + if (rt->dev) + mctp_dev_hold(rt->dev); rcu_read_unlock(); if (!rt->dev)
@@ -891,10 +891,10 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, if (!ext_rt) mctp_route_release(rt); - dev_put(dev); + if (tmp_rt.dev) + mctp_dev_put(tmp_rt.dev); return rc; - } /* route management */
--
2.32.0