6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Geliang Tang <geliang.tang@xxxxxxxx> commit 84c531f54ad9a124a924c9505d74e33d16965146 upstream. This patch adds the ability to send RM_ADDR for local ID 0. Check whether id 0 address is removed, if not, put id 0 into a removing list, pass it to mptcp_pm_remove_addr() to remove id 0 address. There is no reason not to allow the userspace to remove the initial address (ID 0). This special case was not taken into account not letting the userspace to delete all addresses as announced. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/379 Reviewed-by: Matthieu Baerts <matttbe@xxxxxxxxxx> Signed-off-by: Geliang Tang <geliang.tang@xxxxxxxx> Signed-off-by: Mat Martineau <martineau@xxxxxxxxxx> Link: https://lore.kernel.org/r/20231025-send-net-next-20231025-v1-3-db8f25f798eb@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Fixes: d9a4594edabf ("mptcp: netlink: Add MPTCP_PM_CMD_REMOVE") Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/mptcp/pm_userspace.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) --- a/net/mptcp/pm_userspace.c +++ b/net/mptcp/pm_userspace.c @@ -220,6 +220,40 @@ int mptcp_nl_cmd_announce(struct sk_buff return err; } +static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk, + struct genl_info *info) +{ + struct mptcp_rm_list list = { .nr = 0 }; + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + bool has_id_0 = false; + int err = -EINVAL; + + lock_sock(sk); + mptcp_for_each_subflow(msk, subflow) { + if (subflow->local_id == 0) { + has_id_0 = true; + break; + } + } + if (!has_id_0) { + GENL_SET_ERR_MSG(info, "address with id 0 not found"); + goto remove_err; + } + + list.ids[list.nr++] = 0; + + spin_lock_bh(&msk->pm.lock); + mptcp_pm_remove_addr(msk, &list); + spin_unlock_bh(&msk->pm.lock); + + err = 0; + +remove_err: + release_sock(sk); + return err; +} + int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info) { struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; @@ -251,6 +285,11 @@ int mptcp_nl_cmd_remove(struct sk_buff * goto remove_err; } + if (id_val == 0) { + err = mptcp_userspace_pm_remove_id_zero_address(msk, info); + goto remove_err; + } + lock_sock((struct sock *)msk); list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
