6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
commit ca6e55a703ca2894611bb5c5bca8bfd2290fd91e upstream.
The ID 0 is specific per MPTCP connections. The per netns entries cannot
have this special ID 0 then.
But that's different for the userspace PM where the entries are per
connection, they can then use this special ID 0.
Fixes: f40be0db0b76 ("mptcp: unify pm get_flags_and_ifindex_by_id")
Cc: stable@xxxxxxxxxxxxxxx
Acked-by: Geliang Tang <geliang@xxxxxxxxxx>
Reviewed-by: Mat Martineau <martineau@xxxxxxxxxx>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
Link: https://patch.msgid.link/20240819-net-mptcp-pm-reusing-id-v1-11-38035d40de5b@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/mptcp/pm.c | 3 ---
net/mptcp/pm_netlink.c | 4 ++++
2 files changed, 4 insertions(+), 3 deletions(-)
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -435,9 +435,6 @@ int mptcp_pm_get_flags_and_ifindex_by_id
*flags = 0;
*ifindex = 0;
- if (!id)
- return 0;
-
if (mptcp_pm_is_userspace(msk))
return mptcp_userspace_pm_get_flags_and_ifindex_by_id(msk, id, flags, ifindex);
return mptcp_pm_nl_get_flags_and_ifindex_by_id(msk, id, flags, ifindex);
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -1426,6 +1426,10 @@ int mptcp_pm_nl_get_flags_and_ifindex_by
struct sock *sk = (struct sock *)msk;
struct net *net = sock_net(sk);
+ /* No entries with ID 0 */
+ if (id == 0)
+ return 0;
+
rcu_read_lock();
entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id);
if (entry) {
