From 3773d65ae5154ed7df404b050fd7387a36ab5ef3 Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Tue, 20 Feb 2024 16:10:53 +0800 Subject: net: mctp: take ownership of skb in mctp_local_output Currently, mctp_local_output only takes ownership of skb on success, and we may leak an skb if mctp_local_output fails in specific states; the skb ownership isn't transferred until the actual output routing occurs. Instead, make mctp_local_output free the skb on all error paths up to the route action, so it always consumes the passed skb. Fixes: 833ef3b91de6 ("mctp: Populate socket implementation") Signed-off-by: Jeremy Kerr Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20240220081053.1439104-1-jk@codeconstruct.com.au Signed-off-by: Jakub Kicinski --- net/mctp/route.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'net/mctp') diff --git a/net/mctp/route.c b/net/mctp/route.c index 6218dcd07e18..ceee44ea09d9 100644 --- a/net/mctp/route.c +++ b/net/mctp/route.c @@ -888,7 +888,7 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, dev = dev_get_by_index_rcu(sock_net(sk), cb->ifindex); if (!dev) { rcu_read_unlock(); - return rc; + goto out_free; } rt->dev = __mctp_dev_get(dev); rcu_read_unlock(); @@ -903,7 +903,8 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, rt->mtu = 0; } else { - return -EINVAL; + rc = -EINVAL; + goto out_free; } spin_lock_irqsave(&rt->dev->addrs_lock, flags); @@ -966,12 +967,17 @@ int mctp_local_output(struct sock *sk, struct mctp_route *rt, rc = mctp_do_fragment_route(rt, skb, mtu, tag); } + /* route output functions consume the skb, even on error */ + skb = NULL; + out_release: if (!ext_rt) mctp_route_release(rt); mctp_dev_put(tmp_rt.dev); +out_free: + kfree_skb(skb); return rc; } -- cgit v1.2.3