5.15-stable review patch. If anyone has any objections, please let me know.
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From: "Matthieu Baerts (NGI0)" matttbe@kernel.org
commit 6834097fc38c5416701c793da94558cea49c0a1f upstream.
There was a support for signal endpoints, but only when the endpoint's flag was changed during a connection. If an endpoint with the signal and backup was already present, the MP_JOIN reply was not containing the backup flag as expected.
That's confusing to have this inconsistent behaviour. On the other hand, the infrastructure to set the backup flag in the SYN + ACK + MP_JOIN was already there, it was just never set before. Now when requesting the local ID from the path-manager, the backup status is also requested.
Note that when the userspace PM is used, the backup flag can be set if the local address was already used before with a backup flag, e.g. if the address was announced with the 'backup' flag, or a subflow was created with the 'backup' flag.
Fixes: 4596a2c1b7f5 ("mptcp: allow creating non-backup subflows") Cc: stable@vger.kernel.org Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/507 Reviewed-by: Mat Martineau martineau@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Signed-off-by: Paolo Abeni pabeni@redhat.com [ Conflicts in pm_userspace.c because the context has changed in commit 1e07938e29c5 ("net: mptcp: rename netlink handlers to mptcp_pm_nl_<blah>_{doit,dumpit}") which is not in this version. This commit is unrelated to this modification. Conflicts in protocol.h because the context has changed in commit 9ae7846c4b6b ("mptcp: dump addrs in userspace pm list") which is not in this version. This commit is unrelated to this modification. Conflicts in pm.c because the context has changed in commit f40be0db0b76 ("mptcp: unify pm get_flags_and_ifindex_by_id") which is not in this version. This commit is unrelated to this modification. Conflicts in subflow.c, because the commit 4cf86ae84c71 ("mptcp: strict local address ID selection") is not in this version. It is then not needed to modify the subflow_chk_local_id() helper, which is not in this version. Also, in this version, there is no pm_userspace.c, because this PM has been added in v5.19, which also causes conflicts in protocol.h, and pm_netlink.c. Plus the code in pm.c can be simplified, as there is no userspace PM. And the code in pm_netlink.c needs to use addresses_equal() instead of mptcp_addresses_equal(), see commit 4638de5aefe5 ("mptcp: handle local addrs announced by userspace PMs"). The code in pm_netlink.c also needs to be adapted because the pm_nl_get_pernet_from_msk() helper is not in this version, introduced later in commit c682bf536cf4 ("mptcp: add pm_nl_pernet helpers"). ] Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org
Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mptcp/pm.c | 9 +++++++++ net/mptcp/pm_netlink.c | 20 ++++++++++++++++++++ net/mptcp/protocol.h | 2 ++ net/mptcp/subflow.c | 1 + 4 files changed, 32 insertions(+)
--- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -341,6 +341,15 @@ int mptcp_pm_get_local_id(struct mptcp_s return mptcp_pm_nl_get_local_id(msk, skc); }
+bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc) +{ + struct mptcp_addr_info skc_local; + + mptcp_local_address((struct sock_common *)skc, &skc_local); + + return mptcp_pm_nl_is_backup(msk, &skc_local); +} + void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -1014,6 +1014,26 @@ int mptcp_pm_nl_get_local_id(struct mptc return ret; }
+bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc) +{ + struct mptcp_pm_addr_entry *entry; + struct pm_nl_pernet *pernet; + bool backup = false; + + pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); + + rcu_read_lock(); + list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { + if (addresses_equal(&entry->addr, skc, entry->addr.port)) { + backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); + break; + } + } + rcu_read_unlock(); + + return backup; +} + void mptcp_pm_nl_data_init(struct mptcp_sock *msk) { struct mptcp_pm_data *pm = &msk->pm; --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -821,6 +821,7 @@ bool mptcp_pm_add_addr_signal(struct mpt bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, struct mptcp_rm_list *rm_list); int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); +bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc);
void __init mptcp_pm_nl_init(void); void mptcp_pm_nl_data_init(struct mptcp_sock *msk); @@ -828,6 +829,7 @@ void mptcp_pm_nl_work(struct mptcp_sock void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); +bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk); unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk); unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk); --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -97,6 +97,7 @@ static struct mptcp_sock *subflow_token_ return NULL; } subflow_req->local_id = local_id; + subflow_req->request_bkup = mptcp_pm_is_backup(msk, (struct sock_common *)req);
return msk; }