commit 09355f7abb9fbfc1a240be029837921ea417bf4f upstream.
When reacting upon the reception of an ADD_ADDR, the in-kernel PM first
looks for fullmesh endpoints. If there are some, it will pick them,
using their entry ID.
It should set the ID 0 when using the endpoint corresponding to the
initial subflow, it is a special case imposed by the MPTCP specs.
Note that msk->mpc_endpoint_id might not be set when receiving the first
ADD_ADDR from the server. So better to compare the addresses.
Fixes: 1a0d6136c5f0 ("mptcp: local addresses fullmesh")
Cc: stable@xxxxxxxxxxxxxxx
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-v1-12-38035d40de5b@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
[ Conflicts in pm_netlink.c, because the new 'mpc_addr' variable is
added where the 'local' one was, before commit b9d69db87fb7 ("mptcp:
let the in-kernel PM use mixed IPv4 and IPv6 addresses"), that is not
a candidate for the backports. This 'local' variable has been moved to
the new place to reduce the scope, and help with possible future
backports. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
---
net/mptcp/pm_netlink.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 9e16ae1b23fc..a152a3474d2c 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -648,7 +648,7 @@ static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
{
struct sock *sk = (struct sock *)msk;
struct mptcp_pm_addr_entry *entry;
- struct mptcp_addr_info local;
+ struct mptcp_addr_info mpc_addr;
struct pm_nl_pernet *pernet;
unsigned int subflows_max;
int i = 0;
@@ -656,6 +656,8 @@ static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
pernet = pm_nl_get_pernet_from_msk(msk);
subflows_max = mptcp_pm_get_subflows_max(msk);
+ mptcp_local_address((struct sock_common *)msk, &mpc_addr);
+
rcu_read_lock();
list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH))
@@ -673,7 +675,13 @@ static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
if (msk->pm.subflows < subflows_max) {
msk->pm.subflows++;
- addrs[i++] = entry->addr;
+ addrs[i] = entry->addr;
+
+ /* Special case for ID0: set the correct ID */
+ if (mptcp_addresses_equal(&entry->addr, &mpc_addr, entry->addr.port))
+ addrs[i].id = 0;
+
+ i++;
}
}
rcu_read_unlock();
@@ -682,6 +690,8 @@ static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
* 'IPADDRANY' local address
*/
if (!i) {
+ struct mptcp_addr_info local;
+
memset(&local, 0, sizeof(local));
local.family = msk->pm.remote.family;
--
2.45.2
