diff options
| author | Kuniyuki Iwashima <kuniyu@google.com> | 2025-09-17 00:47:25 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-09-18 04:10:22 +0300 |
| commit | 893c49a78d9f85e4b8081b908fb7c407d018106a (patch) | |
| tree | 7be50d092f843bb35adac6f55fe43f58e97388fd /net/mptcp/ctrl.c | |
| parent | 108a86c71c93ff28087994e6107bc99ebe336629 (diff) | |
| download | linux-893c49a78d9f85e4b8081b908fb7c407d018106a.tar.xz | |
mptcp: Use __sk_dst_get() and dst_dev_rcu() in mptcp_active_enable().
mptcp_active_enable() is called from subflow_finish_connect(),
which is icsk->icsk_af_ops->sk_rx_dst_set() and it's not always
under RCU.
Using sk_dst_get(sk)->dev could trigger UAF.
Let's use __sk_dst_get() and dst_dev_rcu().
Fixes: 27069e7cb3d1 ("mptcp: disable active MPTCP in case of blackhole")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250916214758.650211-8-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/mptcp/ctrl.c')
| -rw-r--r-- | net/mptcp/ctrl.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/net/mptcp/ctrl.c b/net/mptcp/ctrl.c index c0e516872b4b..e8ffa62ec183 100644 --- a/net/mptcp/ctrl.c +++ b/net/mptcp/ctrl.c @@ -501,12 +501,15 @@ void mptcp_active_enable(struct sock *sk) struct mptcp_pernet *pernet = mptcp_get_pernet(sock_net(sk)); if (atomic_read(&pernet->active_disable_times)) { - struct dst_entry *dst = sk_dst_get(sk); + struct net_device *dev; + struct dst_entry *dst; - if (dst && dst->dev && (dst->dev->flags & IFF_LOOPBACK)) + rcu_read_lock(); + dst = __sk_dst_get(sk); + dev = dst ? dst_dev_rcu(dst) : NULL; + if (dev && (dev->flags & IFF_LOOPBACK)) atomic_set(&pernet->active_disable_times, 0); - - dst_release(dst); + rcu_read_unlock(); } } |