[PATCH] ip.7: Add not supported by SOCK_STREAM to socket options

From: Oliver Crumrine
Date: Sat Mar 02 2024 - 18:19:56 EST


It was not made clear in several socket options that they were not
supported by SOCK_STREAM; this patch fixes that.

Socket options not supported by SOCK_STREAM are handled in the
ip_cmsg_recv_offset function in net/ipv4/ip_sockglue.c. The function is
called for udp sockets, and indirectly by ping and raw sockets, but not
for TCP sockets, as they don't support these options.

Signed-off-by: Oliver Crumrine <ozlinuxc@xxxxxxxxx>
---
man7/ip.7 | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/man7/ip.7 b/man7/ip.7
index 2b4b06324..104e65feb 100644
--- a/man7/ip.7
+++ b/man7/ip.7
@@ -828,6 +828,9 @@ is not zero, the primary local address of the interface specified by the
index overwrites
.I ipi_spec_dst
for the routing table lookup.
+Not supported for
+.B SOCK_STREAM
+sockets.
.TP
.BR IP_RECVERR " (since Linux 2.2)"
.\" Precisely: since Linux 2.1.15
@@ -989,6 +992,9 @@ in which the kernel returns the original destination address
of the datagram being received.
The ancillary message contains a
.IR "struct sockaddr_in" .
+Not supported for
+.B SOCK_STREAM
+sockets.
.TP
.BR IP_RECVTOS " (since Linux 2.2)"
.\" Precisely: since Linux 2.1.68
@@ -998,6 +1004,9 @@ ancillary message is passed with incoming packets.
It contains a byte which specifies the Type of Service/Precedence
field of the packet header.
Expects a boolean integer flag.
+Not supported for
+.B SOCK_STREAM
+sockets.
.TP
.BR IP_RECVTTL " (since Linux 2.2)"
.\" Precisely: since Linux 2.1.68
--
2.44.0