5.4-stable review patch. If anyone has any objections, please let me know.
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From: Jörn-Thorben Hinz jthinz@mailbox.tu-berlin.de
[ 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@mailbox.tu-berli... Link: https://lore.kernel.org/netdev/0d7cddc9-03fa-43db-a579-14f3e822615b@app.fast... Signed-off-by: Jörn-Thorben Hinz jthinz@mailbox.tu-berlin.de Reviewed-by: Willem de Bruijn willemb@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- 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: