socket: fix option SO_TIMESTAMPING_NEW

The comparison of optname with SO_TIMESTAMPING_NEW is wrong way around,
so SOCK_TSTAMP_NEW will first be set and than reset again. Additionally
move it out of the test for SOF_TIMESTAMPING_RX_SOFTWARE as this seems
unrelated.

This problem happens on 32 bit platforms were the libc has already
switched to struct timespec64 (from SO_TIMExxx_OLD to SO_TIMExxx_NEW
socket options). ptp4l complains with "missing timestamp on transmitted
peer delay request" because the wrong format is received (and
discarded).

Fixes: 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW")
Signed-off-by: Christian Eggers <ceggers@arri.de>
Reviewed-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Reviewed-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/core/sock.c b/net/core/sock.c
index 6c5c6b1..dfe5d80 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1007,8 +1007,6 @@ set_sndbuf:
                __sock_set_timestamps(sk, valbool, true, true);
                break;
        case SO_TIMESTAMPING_NEW:
-               sock_set_flag(sk, SOCK_TSTAMP_NEW);
-               fallthrough;
        case SO_TIMESTAMPING_OLD:
                if (val & ~SOF_TIMESTAMPING_MASK) {
                        ret = -EINVAL;
@@ -1037,16 +1035,14 @@ set_sndbuf:
                }
 
                sk->sk_tsflags = val;
+               sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
+
                if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
                        sock_enable_timestamp(sk,
                                              SOCK_TIMESTAMPING_RX_SOFTWARE);
-               else {
-                       if (optname == SO_TIMESTAMPING_NEW)
-                               sock_reset_flag(sk, SOCK_TSTAMP_NEW);
-
+               else
                        sock_disable_timestamp(sk,
                                               (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
-               }
                break;
 
        case SO_RCVLOWAT: