[PATCH 6.1 073/197] mptcp: check addrs list in userspace_pm_get_local_id

Greg Kroah-Hartman
2024-02-20T21:03:16Z

From: Geliang Tang <geliang@kernel.org>

commit f012d796a6de662692159c539689e47e662853a8 upstream.

Before adding a new entry in mptcp_userspace_pm_get_local_id(), it's
better to check whether this address is already in userspace pm local
address list. If it's in the list, no need to add a new entry, just
return it's address ID and use this address.

Fixes: 8b20137012d9 ("mptcp: read attributes of addr entries managed by userspace PMs")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/mptcp/pm_userspace.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -132,10 +132,21 @@ int mptcp_userspace_pm_get_flags_and_ifi
int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk,
struct mptcp_addr_info *skc)
{
- struct mptcp_pm_addr_entry new_entry;
+ struct mptcp_pm_addr_entry *entry = NULL, *e, new_entry;
__be16 msk_sport = ((struct inet_sock *)
inet_sk((struct sock *)msk))->inet_sport;

+ spin_lock_bh(&msk->pm.lock);
+ list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) {
+ if (mptcp_addresses_equal(&e->addr, skc, false)) {
+ entry = e;
+ break;
+ }
+ }
+ spin_unlock_bh(&msk->pm.lock);
+ if (entry)
+ return entry->addr.id;
+
memset(&new_entry, 0, sizeof(struct mptcp_pm_addr_entry));
new_entry.addr = *skc;
new_entry.addr.id = 0;