On Wed, Jul 21, 2021 at 2:42 PM Marcelo Ricardo Leitner
[off-list ref] wrote:

On Wed, Jul 21, 2021 at 12:08:25PM -0400, Xin Long wrote:

quoted

Currently, in sctp_packet_config(), sctp_transport_pmtu_check() is
called to update transport pathmtu with dst's mtu when dst's mtu
has been changed by non sctp stack like xfrm.

However, this should only happen when SPP_PMTUD_ENABLE is set, no
matter where dst's mtu changed. This patch is to fix by checking
SPP_PMTUD_ENABLE flag before calling sctp_transport_pmtu_check().

Thanks Jacek for reporting and looking into this issue.

Fixes: 69fec325a643 ('Revert "sctp: remove sctp_transport_pmtu_check"')
Reported-by: Jacek Szafraniec <redacted>
Tested-by: Jacek Szafraniec <redacted>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 net/sctp/output.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/sctp/output.c b/net/sctp/output.c
index 9032ce60d50e..8d5708dd2a1f 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c

@@ -104,8 +104,8 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag,
              if (asoc->param_flags & SPP_PMTUD_ENABLE)
                      sctp_assoc_sync_pmtu(asoc);
      } else if (!sctp_transport_pl_enabled(tp) &&
-                !sctp_transport_pmtu_check(tp)) {
-             if (asoc->param_flags & SPP_PMTUD_ENABLE)
+                asoc->param_flags & SPP_PMTUD_ENABLE)

Lacks a '{' here at the end of the line.

ah, right, sorry, reposted.

Other than that:
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>

(please add it on the v2)

quoted

+             if (!sctp_transport_pmtu_check(tp))
                      sctp_assoc_sync_pmtu(asoc);
      }

--
2.27.0