linux.git/include/linux/can/dev.h, branch v5.11.8 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git can: drivers: introduce helpers to access Classical CAN DLC values 2020-11-20T11:05:14+00:00 Oliver Hartkopp socketcan@hartkopp.net 2020-11-10T15:49:12+00:00 e8e73562ce0b24d691ad35df3de34b324248458f This patch adds the following helper to functions to access Classical CAN DLC values. can_get_cc_dlc(): get the data length code for Classical CAN raw DLC access can_frame_set_cc_len(): set len and len8_dlc value for Classical CAN raw DLC access Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/r/20201110154913.1404582-2-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
This patch adds the following helper to functions to access Classical CAN DLC
values.

can_get_cc_dlc(): get the data length code for Classical CAN raw DLC access
can_frame_set_cc_len(): set len and len8_dlc value for Classical CAN raw DLC access

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110154913.1404582-2-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: rename CAN FD related can_len2dlc and can_dlc2len helpers 2020-11-20T11:05:14+00:00 Oliver Hartkopp socketcan@hartkopp.net 2020-11-10T10:18:49+00:00 3ab4ce0d6fa8c93d41df4a74ec8d2c9198be2109 The helper functions can_len2dlc and can_dlc2len are only relevant for CAN FD data length code (DLC) conversion. To fit the introduced can_cc_dlc2len for Classical CAN we rename: can_dlc2len -> can_fd_dlc2len to get the payload length from the DLC can_len2dlc -> can_fd_len2dlc to get the DLC from the payload length Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/r/20201110101852.1973-6-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
The helper functions can_len2dlc and can_dlc2len are only relevant for
CAN FD data length code (DLC) conversion.

To fit the introduced can_cc_dlc2len for Classical CAN we rename:

can_dlc2len -> can_fd_dlc2len to get the payload length from the DLC
can_len2dlc -> can_fd_len2dlc to get the DLC from the payload length

Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-6-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: replace can_dlc as variable/element for payload length 2020-11-20T11:04:12+00:00 Oliver Hartkopp socketcan@hartkopp.net 2020-11-20T10:04:44+00:00 c7b74967799b1af52b3045d69d4c26836b2d41de The naming of can_dlc as element of struct can_frame and also as variable name is misleading as it claims to be a 'data length CODE' but in reality it always was a plain data length. With the indroduction of a new 'len' element in struct can_frame we can now remove can_dlc as name and make clear which of the former uses was a plain length (-> 'len') or a data length code (-> 'dlc') value. Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/r/20201120100444.3199-1-socketcan@hartkopp.net [mkl: gs_usb: keep struct gs_host_frame::can_dlc as is] Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
The naming of can_dlc as element of struct can_frame and also as variable
name is misleading as it claims to be a 'data length CODE' but in reality
it always was a plain data length.

With the indroduction of a new 'len' element in struct can_frame we can now
remove can_dlc as name and make clear which of the former uses was a plain
length (-> 'len') or a data length code (-> 'dlc') value.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201120100444.3199-1-socketcan@hartkopp.net
[mkl: gs_usb: keep struct gs_host_frame::can_dlc as is]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: remove obsolete get_canfd_dlc() macro 2020-11-20T08:43:30+00:00 Oliver Hartkopp socketcan@hartkopp.net 2020-11-10T10:18:47+00:00 cd1124e76d740327be5d8f9ce3785ce1119daf4b The macro was always used together with can_dlc2len() which sanitizes the given dlc value on its own. Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/r/20201110101852.1973-4-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
The macro was always used together with can_dlc2len() which sanitizes the
given dlc value on its own.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-4-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: rename get_can_dlc() macro with can_cc_dlc2len() 2020-11-20T08:43:29+00:00 Oliver Hartkopp socketcan@hartkopp.net 2020-11-10T10:18:46+00:00 69d98969a0540039fc04e0f22bbe9f41b0a13d66 The get_can_dlc() macro is used to ensure the payload length information of the Classical CAN frame to be max 8 bytes (the CAN_MAX_DLEN). Rename the macro and use the correct constant in preparation of the len/dlc cleanup for Classical CAN frames. Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/r/20201110101852.1973-3-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
The get_can_dlc() macro is used to ensure the payload length information of
the Classical CAN frame to be max 8 bytes (the CAN_MAX_DLEN).

Rename the macro and use the correct constant in preparation of the len/dlc
cleanup for Classical CAN frames.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-3-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: dev: add a helper function to calculate the duration of one bit 2020-10-07T21:17:45+00:00 Vincent Mailhol mailhol.vincent@wanadoo.fr 2020-10-02T15:41:49+00:00 1c47fa6b31c2683f03bc2f9174902bb7dcd35d83 Rename macro CAN_CALC_SYNC_SEG to CAN_SYNC_SEG and make it available through include/linux/can/dev.h Add an helper function can_bit_time() which returns the duration (in time quanta) of one CAN bit. Rationale for this patch: the sync segment and the bit time are two concepts which are defined in the CAN ISO standard. Device drivers for CAN might need those. Please refer to ISO 11898-1:2015, section 11.3.1.1 "Bit time" for additional information. Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20201002154219.4887-6-mailhol.vincent@wanadoo.fr [mkl: Let can_bit_time() return an unsinged int, make argument const] Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
Rename macro CAN_CALC_SYNC_SEG to CAN_SYNC_SEG and make it available
through include/linux/can/dev.h

Add an helper function can_bit_time() which returns the duration (in
time quanta) of one CAN bit.

Rationale for this patch: the sync segment and the bit time are two
concepts which are defined in the CAN ISO standard. Device drivers for
CAN might need those.

Please refer to ISO 11898-1:2015, section 11.3.1.1 "Bit time" for
additional information.

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20201002154219.4887-6-mailhol.vincent@wanadoo.fr
[mkl: Let can_bit_time() return an unsinged int, make argument const]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: dev: fix type of get_can_dlc() and get_canfd_dlc() macros 2020-10-06T20:44:27+00:00 Vincent Mailhol mailhol.vincent@wanadoo.fr 2020-10-02T15:41:46+00:00 f55a52bb2cdbc5a92ca209d0ada90a490a188f58 The macros get_can_dlc() and get_canfd_dlc() are not visible in userland. As such, type u8 should be preferred over type __u8. Reference: https://lkml.org/lkml/2020/10/1/708 Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20201002154219.4887-3-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
The macros get_can_dlc() and get_canfd_dlc() are not visible in
userland. As such, type u8 should be preferred over type __u8.

Reference: https://lkml.org/lkml/2020/10/1/708
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20201002154219.4887-3-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: dev: can_put_echo_skb(): propagate error in case of errors 2020-09-21T08:13:16+00:00 Marc Kleine-Budde mkl@pengutronix.de 2020-09-15T22:35:01+00:00 80a71815d8cd1be6481ad16fad3167f095045a06 The function can_put_echo_skb() can fail for several reasons. It may fail due to OOM, but when it fails it's usually due to locking problems in the driver. In order to help developing and debugging of new drivers propagate error value in case of errors. Link: https://lore.kernel.org/r/20200915223527.1417033-12-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
The function can_put_echo_skb() can fail for several reasons. It may
fail due to OOM, but when it fails it's usually due to locking problems
in the driver.

In order to help developing and debugging of new drivers propagate error
value in case of errors.

Link: https://lore.kernel.org/r/20200915223527.1417033-12-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: include: fix spelling mistakes 2020-09-21T08:13:15+00:00 Marc Kleine-Budde mkl@pengutronix.de 2020-09-15T22:34:53+00:00 49347755a84052fd1317c3897c7cea954c8f89fe This patch fixes spelling erros found by "codespell" in the include/linux/can subtree. Link: https://lore.kernel.org/r/20200915223527.1417033-4-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
This patch fixes spelling erros found by "codespell" in the
include/linux/can subtree.

Link: https://lore.kernel.org/r/20200915223527.1417033-4-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: can_dropped_invalid_skb(): ensure an initialized headroom in outgoing CAN sk_buffs 2020-01-02T14:34:27+00:00 Oliver Hartkopp socketcan@hartkopp.net 2019-12-07T18:34:18+00:00 e7153bf70c3496bac00e7e4f395bb8d8394ac0ea KMSAN sysbot detected a read access to an untinitialized value in the headroom of an outgoing CAN related sk_buff. When using CAN sockets this area is filled appropriately - but when using a packet socket this initialization is missing. The problematic read access occurs in the CAN receive path which can only be triggered when the sk_buff is sent through a (virtual) CAN interface. So we check in the sending path whether we need to perform the missing initializations. Fixes: d3b58c47d330d ("can: replace timestamp as unique skb attribute") Reported-by: syzbot+b02ff0707a97e4e79ebb@syzkaller.appspotmail.com Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Tested-by: Oliver Hartkopp <socketcan@hartkopp.net> Cc: linux-stable <stable@vger.kernel.org> # >= v4.1 Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> 
KMSAN sysbot detected a read access to an untinitialized value in the
headroom of an outgoing CAN related sk_buff. When using CAN sockets this
area is filled appropriately - but when using a packet socket this
initialization is missing.

The problematic read access occurs in the CAN receive path which can
only be triggered when the sk_buff is sent through a (virtual) CAN
interface. So we check in the sending path whether we need to perform
the missing initializations.

Fixes: d3b58c47d330d ("can: replace timestamp as unique skb attribute")
Reported-by: syzbot+b02ff0707a97e4e79ebb@syzkaller.appspotmail.com
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org> # >= v4.1
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>