From: Cong Wang <[email protected]> syzbot is able to setup kTLS on an SMC socket, which coincidentally uses sk_user_data too, later, kTLS treats it as psock so triggers a refcnt warning. The cause is that smc_setsockopt() simply calls TCP setsockopt(). I do not think it makes sense to setup kTLS on top of SMC, so we can just disallow this.
Reported-and-tested-by: [email protected] Cc: John Fastabend <[email protected]> Cc: Karsten Graul <[email protected]> Signed-off-by: Cong Wang <[email protected]> --- net/smc/af_smc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 47340b3b514f..0d4d6d28f20c 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -2162,6 +2162,9 @@ static int smc_setsockopt(struct socket *sock, int level, int optname, struct smc_sock *smc; int val, rc; + if (optname == TCP_ULP) + return -EOPNOTSUPP; + smc = smc_sk(sk); /* generic setsockopts reaching us here always apply to the @@ -2186,7 +2189,6 @@ static int smc_setsockopt(struct socket *sock, int level, int optname, if (rc || smc->use_fallback) goto out; switch (optname) { - case TCP_ULP: case TCP_FASTOPEN: case TCP_FASTOPEN_CONNECT: case TCP_FASTOPEN_KEY: -- 2.25.1
