Commit 924e464f authored Apr 20, 2021 by Erik Flodin Committed by Marc Kleine-Budde Apr 24, 2021

can: add a note that RECV_OWN_MSGS frames are subject to filtering

Some parts of the documentation may lead the reader to think that the
socket's own frames are always received when CAN_RAW_RECV_OWN_MSGS is
enabled, but all frames are subject to filtering.

As explained by Marc Kleine-Budde:

On TX complete of a CAN frame it's pushed into the RX path of the
networking stack, along with the information of the originating socket.

Then the CAN frame is delivered into AF_CAN, where it is passed on to
all registered receivers depending on filters. One receiver is the
sending socket in CAN_RAW. Then in CAN_RAW the it is checked if the
sending socket has RECV_OWN_MSGS enabled.

Link: https://lore.kernel.org/r/20210420191212.42753-1-erik@flodin.me


Signed-off-by: Erik Flodin <erik@flodin.me>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

parent 1c9690dd

Documentation/networking/can.rst

+2 −0

Original line number	Diff line number	Diff line
		@@ -608,6 +608,8 @@ demand:
		setsockopt(s, SOL_CAN_RAW, CAN_RAW_RECV_OWN_MSGS,
		&recv_own_msgs, sizeof(recv_own_msgs));

		Note that reception of a socket's own CAN frames are subject to the same
		filtering as other CAN frames (see :ref:`socketcan-rawfilter`).

		.. _socketcan-rawfd: