6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: YonglongLi <liyonglong@xxxxxxxxxxxxxxx>
commit 40eec1795cc27b076d49236649a29507c7ed8c2d upstream.
The creation of new subflows can fail for different reasons. If no
subflow have been created using the received ADD_ADDR, the related
counters should not be updated, otherwise they will never be decremented
for events related to this ID later on.
For the moment, the number of accepted ADD_ADDR is only decremented upon
the reception of a related RM_ADDR, and only if the remote address ID is
currently being used by at least one subflow. In other words, if no
subflow can be created with the received address, the counter will not
be decremented. In this case, it is then important not to increment
pm.add_addr_accepted counter, and not to modify pm.accept_addr bit.
Note that this patch does not modify the behaviour in case of failures
later on, e.g. if the MP Join is dropped or rejected.
The "remove invalid addresses" MP Join subtest has been modified to
validate this case. The broadcast IP address is added before the "valid"
address that will be used to successfully create a subflow, and the
limit is decreased by one: without this patch, it was not possible to
create the last subflow, because:
- the broadcast address would have been accepted even if it was not
usable: the creation of a subflow to this address results in an error,
- the limit of 2 accepted ADD_ADDR would have then been reached.
Fixes: 01cacb00b35c ("mptcp: add netlink-based PM")
Cc: stable@xxxxxxxxxxxxxxx
Co-developed-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
Signed-off-by: YonglongLi <liyonglong@xxxxxxxxxxxxxxx>
Reviewed-by: Mat Martineau <martineau@xxxxxxxxxx>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240607-upstream-net-20240607-misc-fixes-v1-3-1ab9ddfa3d00@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/mptcp/pm_netlink.c | 16 ++++++++++------
tools/testing/selftests/net/mptcp/mptcp_join.sh | 4 ++--
2 files changed, 12 insertions(+), 8 deletions(-)
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -685,6 +685,7 @@ static void mptcp_pm_nl_add_addr_receive
unsigned int add_addr_accept_max;
struct mptcp_addr_info remote;
unsigned int subflows_max;
+ bool sf_created = false;
int i, nr;
add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
@@ -712,15 +713,18 @@ static void mptcp_pm_nl_add_addr_receive
if (nr == 0)
return;
- msk->pm.add_addr_accepted++;
- if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
- msk->pm.subflows >= subflows_max)
- WRITE_ONCE(msk->pm.accept_addr, false);
-
spin_unlock_bh(&msk->pm.lock);
for (i = 0; i < nr; i++)
- __mptcp_subflow_connect(sk, &addrs[i], &remote);
+ if (__mptcp_subflow_connect(sk, &addrs[i], &remote) == 0)
+ sf_created = true;
spin_lock_bh(&msk->pm.lock);
+
+ if (sf_created) {
+ msk->pm.add_addr_accepted++;
+ if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
+ msk->pm.subflows >= subflows_max)
+ WRITE_ONCE(msk->pm.accept_addr, false);
+ }
}
void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -2393,10 +2393,10 @@ remove_tests()
if reset "remove invalid addresses"; then
pm_nl_set_limits $ns1 3 3
pm_nl_add_endpoint $ns1 10.0.12.1 flags signal
- pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
# broadcast IP: no packet for this address will be received on ns1
pm_nl_add_endpoint $ns1 224.0.0.1 flags signal
- pm_nl_set_limits $ns2 3 3
+ pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+ pm_nl_set_limits $ns2 2 2
addr_nr_ns1=-3 speed=10 \
run_tests $ns1 $ns2 10.0.1.1
chk_join_nr 1 1 1
