In mptcp_pm_create_subflow_or_signal_addr(), rcu_read_(un)lock() are used as expected to iterate over the list of local addresses, but list_for_each_entry() was used instead of list_for_each_entry_rcu() in __lookup_addr(). It is important to use this variant which adds the required READ_ONCE() (and diagnostic checks if enabled).
Because __lookup_addr() is also used in mptcp_pm_nl_set_flags() where it is called under the pernet->lock and not rcu_read_lock(), an extra condition is then passed to help the diagnostic checks making sure either the associated spin lock or the RCU lock is held.
Fixes: 86e39e04482b ("mptcp: keep track of local endpoint still available for each msk") Cc: stable@vger.kernel.org Reviewed-by: Geliang Tang geliang@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org --- net/mptcp/pm_netlink.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index db586a5b3866f66a24431d7f2cab566f89102885..45a2b5f05d38b0e7f334578f5ee6923a8ff8f7b2 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -524,7 +524,8 @@ __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info) { struct mptcp_pm_addr_entry *entry;
- list_for_each_entry(entry, &pernet->local_addr_list, list) { + list_for_each_entry_rcu(entry, &pernet->local_addr_list, list, + lockdep_is_held(&pernet->lock)) { if (mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) return entry; }