5.4-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 2c3c5df139345..a3ca522434a6e 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1309,9 +1309,16 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
break;
case SO_LINGER:
+ case SO_TIMESTAMPING_NEW:
lv = sizeof(v.ling);
- v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
- v.ling.l_linger = sk->sk_lingertime / HZ;
+ /* 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.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
+ v.ling.l_linger = sk->sk_lingertime / HZ;
+ }
break;
case SO_BSDCOMPAT:
--
2.43.0
