From: Paolo Abeni <pabeni@xxxxxxxxxx>
commit 2c02d41d71f90a5168391b6a5f2954112ba2307c upstream.
When an ULP-enabled socket enters the LISTEN status, the listener ULP data
pointer is copied inside the child/accepted sockets by sk_clone_lock().
The relevant ULP can take care of de-duplicating the context pointer via
the clone() operation, but only MPTCP and SMC implement such op.
Other ULPs may end-up with a double-free at socket disposal time.
We can't simply clear the ULP data at clone time, as TLS replaces the
socket ops with custom ones assuming a valid TLS ULP context is
available.
Instead completely prevent clone-less ULP sockets from entering the
LISTEN status.
Fixes: 734942cc4ea6 ("tcp: ULP infrastructure")
Reported-by: slipper <slipper.alive@xxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Link: https://lore.kernel.org/r/4b80c3d1dbe3d0ab072f80450c202d9bc88b4b03.1672740602.git.pabeni@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/inet_connection_sock.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -902,11 +902,25 @@ void inet_csk_prepare_forced_close(struc
}
EXPORT_SYMBOL(inet_csk_prepare_forced_close);
+static int inet_ulp_can_listen(const struct sock *sk)
+{
+ const struct inet_connection_sock *icsk = inet_csk(sk);
+
+ if (icsk->icsk_ulp_ops)
+ return -EINVAL;
+
+ return 0;
+}
+
int inet_csk_listen_start(struct sock *sk, int backlog)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct inet_sock *inet = inet_sk(sk);
- int err = -EADDRINUSE;
+ int err;
+
+ err = inet_ulp_can_listen(sk);
+ if (unlikely(err))
+ return err;
reqsk_queue_alloc(&icsk->icsk_accept_queue);
