The J1939 standard requires the transmission of messages of length 0.
For example proprietary messages are specified with a data length of 0
to 1785. The transmission of such messages is not possible. Sending
results in no error being returned but no corresponding can frame
being generated.
Enable the transmission of zero length J1939 messages. In order to
facilitate this two changes are necessary:
1) If the transmission of a new message is requested from user space
the message is segmented in j1939_sk_send_loop(). Let the segmentation
take into account zero length messages, do not terminate immediately,
queue the corresponding skb.
2) j1939_session_skb_get_by_offset() selects the next skb to transmit
for a session. Take into account that there might be zero length skbs
in the queue.
Signed-off-by: Alexander Hölzl <alexander.hoelzl@gmx.net>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/20250205174651.103238-1-alexander.hoelzl@gmx.net
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Cc: stable@vger.kernel.org
[mkl: commit message rephrased]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The Linux socket API currently allows setting SO_PRIORITY at the
socket level, applying a uniform priority to all packets sent through
that socket. The exception to this is IP_TOS, when the priority value
is calculated during the handling of
ancillary data, as implemented in commit f02db315b8 ("ipv4: IP_TOS
and IP_TTL can be specified as ancillary data").
However, this is a computed
value, and there is currently no mechanism to set a custom priority
via control messages prior to this patch.
According to this patch, if SO_PRIORITY is specified as ancillary data,
the packet is sent with the priority value set through
sockc->priority, overriding the socket-level values
set via the traditional setsockopt() method. This is analogous to
the existing support for SO_MARK, as implemented in
commit c6af0c227a ("ip: support SO_MARK cmsg").
If both cmsg SO_PRIORITY and IP_TOS are passed, then the one that
takes precedence is the last one in the cmsg list.
This patch has the side effect that raw_send_hdrinc now interprets cmsg
IP_TOS.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Suggested-by: Ferenc Fejes <fejes@inf.elte.hu>
Signed-off-by: Anna Emese Nyiri <annaemesenyiri@gmail.com>
Link: https://patch.msgid.link/20241213084457.45120-3-annaemesenyiri@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The last type of sockets which supports SOF_TIMESTAMPING_OPT_ID is RAW
sockets. To add new option this patch converts all callers (direct and
indirect) of _sock_tx_timestamp to provide sockcm_cookie instead of
tsflags. And while here fix __sock_tx_timestamp to receive tsflags as
__u32 instead of __u16.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
Link: https://patch.msgid.link/20241001125716.2832769-3-vadfed@meta.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cross-merge networking fixes after downstream PR.
No conflicts.
Adjacent changes:
e3f02f32a0 ("ionic: fix kernel panic due to multi-buffer handling")
d9c0420999 ("ionic: Mark error paths in the data path as unlikely")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch enhances error handling in scenarios with RTS (Request to
Send) messages arriving closely. It replaces the less informative WARN_ON_ONCE
backtraces with a new error handling method. This provides clearer error
messages and allows for the early termination of problematic sessions.
Previously, sessions were only released at the end of j1939_xtp_rx_rts().
Potentially this could be reproduced with something like:
testj1939 -r vcan0:0x80 &
while true; do
# send first RTS
cansend vcan0 18EC8090#1014000303002301;
# send second RTS
cansend vcan0 18EC8090#1014000303002301;
# send abort
cansend vcan0 18EC8090#ff00000000002301;
done
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Reported-by: syzbot+daa36413a5cedf799ae4@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/all/20231117124959.961171-1-o.rempel@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Marc Kleine-Budde says:
====================
pull-request: can-next 2024-02-20
this is a pull request of 9 patches for net-next/master.
The first patch is by Francesco Dolcini and removes a redundant check
for pm_clock_support from the m_can driver.
Martin Hundebøll contributes 3 patches to the m_can/tcan4x5x driver to
allow resume upon RX of a CAN frame.
3 patches by Srinivas Goud add support for ECC statistics to the
xilinx_can driver.
The last 2 patches are by Oliver Hartkopp and me, target the CAN RAW
protocol and fix an error in the getsockopt() for CAN-XL introduced in
the previous pull request to net-next (linux-can-next-for-6.9-20240213).
linux-can-next-for-6.9-20240220
* tag 'linux-can-next-for-6.9-20240220' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next:
can: raw: raw_getsockopt(): reduce scope of err
can: raw: fix getsockopt() for new CAN_RAW_XL_VCID_OPTS
can: xilinx_can: Add ethtool stats interface for ECC errors
can: xilinx_can: Add ECC support
dt-bindings: can: xilinx_can: Add 'xlnx,has-ecc' optional property
can: tcan4x5x: support resuming from rx interrupt signal
can: m_can: allow keeping the transceiver running in suspend
dt-bindings: can: tcan4x5x: Document the wakeup-source flag
can: m_can: remove redundant check for pm_clock_support
====================
Link: https://lore.kernel.org/r/20240220085130.2936533-1-mkl@pengutronix.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The following 3 locks would race against each other, causing the
deadlock situation in the Syzbot bug report:
- j1939_socks_lock
- active_session_list_lock
- sk_session_queue_lock
A reasonable fix is to change j1939_socks_lock to an rwlock, since in
the rare situations where a write lock is required for the linked list
that j1939_socks_lock is protecting, the code does not attempt to
acquire any more locks. This would break the circular lock dependency,
where, for example, the current thread already locks j1939_socks_lock
and attempts to acquire sk_session_queue_lock, and at the same time,
another thread attempts to acquire j1939_socks_lock while holding
sk_session_queue_lock.
NOTE: This patch along does not fix the unregister_netdevice bug
reported by Syzbot; instead, it solves a deadlock situation to prepare
for one or more further patches to actually fix the Syzbot bug, which
appears to be a reference counting problem within the j1939 codebase.
Reported-by: <syzbot+1591462f226d9cbf0564@syzkaller.appspotmail.com>
Signed-off-by: Ziqi Zhao <astrajoan@yahoo.com>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/all/20230721162226.8639-1-astrajoan@yahoo.com
[mkl: remove unrelated newline change]
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
CAN XL data frames contain an 8-bit virtual CAN network identifier (VCID).
A VCID value of zero represents an 'untagged' CAN XL frame.
To receive and send these optional VCIDs via CAN_RAW sockets a new socket
option CAN_RAW_XL_VCID_OPTS is introduced to define/access VCID content:
- tx: set the outgoing VCID value by the kernel (one fixed 8-bit value)
- tx: pass through VCID values from the user space (e.g. for traffic replay)
- rx: apply VCID receive filter (value/mask) to be passed to the user space
With the 'tx pass through' option CAN_RAW_XL_VCID_TX_PASS all valid VCID
values can be sent, e.g. to replay full qualified CAN XL traffic.
The VCID value provided for the CAN_RAW_XL_VCID_TX_SET option will
override the VCID value in the struct canxl_frame.prio defined for
CAN_RAW_XL_VCID_TX_PASS when both flags are set.
With a rx_vcid_mask of zero all possible VCID values (0x00 - 0xFF) are
passed to the user space when the CAN_RAW_XL_VCID_RX_FILTER flag is set.
Without this flag only untagged CAN XL frames (VCID = 0x00) are delivered
to the user space (default).
The 8-bit VCID is stored inside the CAN XL prio element (only in CAN XL
frames!) to not interfere with other CAN content or the CAN filters
provided by the CAN_RAW sockets and kernel infrastruture.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20240212213550.18516-1-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The ISO15765-2 standard supports to take the PDUs communication parameters
blocksize (BS) and Separation Time minimum (STmin) either from the first
received flow control (FC) "static" or from every received FC "dynamic".
Add a new CAN_ISOTP_DYN_FC_PARMS flag to support dynamic FC parameters.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20231208165729.3011-1-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
