| Message ID | db472a753375c011d3dc7b810262935473e481aa.1631821658.git.dcaratti@redhat.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | [mptcp-net] mptcp: allow changing the 'backup' bit when no sockets are open | expand |
On Thu, 16 Sep 2021, Davide Caratti wrote: > current Linux refuses to change the 'backup' bit of MPTCP endpoints, i.e. > using MPTCP_PM_CMD_SET_FLAGS, unless it finds (at least) one subflow that > matches the endpoint address. There is no reason for that, so we can make > mptcp_nl_addr_backup() return without error even when 0 MPTCP sockets are > open and no MP_PRIO message is sent out. > > Fixes: 0f9f696a502e ("mptcp: add set_flags command in PM netlink") > Signed-off-by: Davide Caratti <dcaratti@redhat.com> > --- > net/mptcp/pm_netlink.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c > index c4f9a5ce3815..8a7048c5b9b4 100644 > --- a/net/mptcp/pm_netlink.c > +++ b/net/mptcp/pm_netlink.c > @@ -1678,7 +1678,7 @@ static int mptcp_nl_addr_backup(struct net *net, > { > long s_slot = 0, s_num = 0; > struct mptcp_sock *msk; > - int ret = -EINVAL; > + int ret = 0; Hi Davide & Geliang - The ret value in mptcp_nl_addr_backup() can still get set to -EINVAL if mptcp_pm_nl_mp_prio_send_ack() returns that error and it happens to be the last token. So the error is not consistently propagated, and it doesn't seem like it's useful to propagate the -EINVAL to mptcp_nl_cmd_set_flags() anyway. How about making mptcp_nl_cmd_set_flags() ignore the value returned by mptcp_nl_addr_backup()? -- Mat Martineau Intel
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index c4f9a5ce3815..8a7048c5b9b4 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -1678,7 +1678,7 @@ static int mptcp_nl_addr_backup(struct net *net, { long s_slot = 0, s_num = 0; struct mptcp_sock *msk; - int ret = -EINVAL; + int ret = 0; while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { struct sock *sk = (struct sock *)msk;
current Linux refuses to change the 'backup' bit of MPTCP endpoints, i.e. using MPTCP_PM_CMD_SET_FLAGS, unless it finds (at least) one subflow that matches the endpoint address. There is no reason for that, so we can make mptcp_nl_addr_backup() return without error even when 0 MPTCP sockets are open and no MP_PRIO message is sent out. Fixes: 0f9f696a502e ("mptcp: add set_flags command in PM netlink") Signed-off-by: Davide Caratti <dcaratti@redhat.com> --- net/mptcp/pm_netlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)