5.15-stable review patch. If anyone has any objections, please let me know.
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From: Matt Johnston matt@codeconstruct.com.au
[ Upstream commit 52024cd6ec71a6ca934d0cc12452bd8d49850679 ]
Bind lookup runs under RCU, so ensure that a socket doesn't go away in the middle of a lookup.
Fixes: 833ef3b91de6 ("mctp: Populate socket implementation") Signed-off-by: Matt Johnston matt@codeconstruct.com.au Link: https://patch.msgid.link/20250410-mctp-rcu-sock-v1-1-872de9fdc877@codeconstr... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/mctp/af_mctp.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c index 0ca031866ce1a..53b3a294b0424 100644 --- a/net/mctp/af_mctp.c +++ b/net/mctp/af_mctp.c @@ -253,6 +253,9 @@ static int mctp_sk_hash(struct sock *sk) { struct net *net = sock_net(sk);
+ /* Bind lookup runs under RCU, remain live during that. */ + sock_set_flag(sk, SOCK_RCU_FREE); + mutex_lock(&net->mctp.bind_lock); sk_add_node_rcu(sk, &net->mctp.binds); mutex_unlock(&net->mctp.bind_lock);