6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jörn-Thorben Hinz <jthinz@xxxxxxxxxxxxxxxxxxxx> [ Upstream commit 7f6ca95d16b96567ce4cf458a2790ff17fa620c3 ] Commit 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW") added the new socket option SO_TIMESTAMPING_NEW. Setting the option is handled in sk_setsockopt(), querying it was not handled in sk_getsockopt(), though. Following remarks on an earlier submission of this patch, keep the old behavior of getsockopt(SO_TIMESTAMPING_OLD) which returns the active flags even if they actually have been set through SO_TIMESTAMPING_NEW. The new getsockopt(SO_TIMESTAMPING_NEW) is stricter, returning flags only if they have been set through the same option. Fixes: 9718475e6908 ("socket: Add SO_TIMESTAMPING_NEW") Link: https://lore.kernel.org/lkml/20230703175048.151683-1-jthinz@xxxxxxxxxxxxxxxxxxxx/ Link: https://lore.kernel.org/netdev/0d7cddc9-03fa-43db-a579-14f3e822615b@xxxxxxxxxxxxxxxx/ Signed-off-by: Jörn-Thorben Hinz <jthinz@xxxxxxxxxxxxxxxxxxxx> Reviewed-by: Willem de Bruijn <willemb@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/core/sock.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/net/core/sock.c b/net/core/sock.c index 49b7f252ddae4..0d8754ec837dc 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1704,9 +1704,16 @@ int sk_getsockopt(struct sock *sk, int level, int optname, break; case SO_TIMESTAMPING_OLD: + case SO_TIMESTAMPING_NEW: lv = sizeof(v.timestamping); - v.timestamping.flags = READ_ONCE(sk->sk_tsflags); - v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc); + /* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only + * returning the flags when they were set through the same option. + * Don't change the beviour for the old case SO_TIMESTAMPING_OLD. + */ + if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) { + v.timestamping.flags = READ_ONCE(sk->sk_tsflags); + v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc); + } break; case SO_RCVTIMEO_OLD: -- 2.43.0