kernel/linux.git/drivers/net/mctp, branch v5.19

mctp i2c: correct mctp_i2c_header_create result

2022-04-01T11:04:15+00:00

header_ops.create should return the length of the header, instead mctp_i2c_head_create() returned 0. This didn't cause any problem because the MCTP stack accepted 0 as success. Fixes: f5b8abf9fc3d ("mctp i2c: MCTP I2C binding driver") Signed-off-by: Matt Johnston Signed-off-by: David S. Miller

mctp: serial: Use netif_rx().

2022-03-06T11:05:31+00:00

Since commit baebdf48c3600 ("net: dev: Makes sure netif_rx() can be invoked in any context.") the function netif_rx() can be used in preemptible/thread context as well as in interrupt context. Use netif_rx(). Cc: Jeremy Kerr Cc: Matt Johnston Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: David S. Miller

mctp i2c: Fix hard head TX bounds length check

2022-02-26T06:23:33+00:00

We should be testing the length before fitting into the u8 byte_count. This is just a sanity check, the MCTP stack should have limited to MTU which is checked, and we check consistency later in mctp_i2c_xmit(). Found by Smatch mctp_i2c_header_create() warn: impossible condition '(hdr->byte_count > 255) => (0-255 > 255)' Signed-off-by: Matt Johnston Signed-off-by: Jakub Kicinski

mctp i2c: Fix potential use-after-free

2022-02-26T06:23:29+00:00

The skb is handed off to netif_rx() which may free it. Found by Smatch. Reported-by: Dan Carpenter Signed-off-by: Matt Johnston Signed-off-by: Jakub Kicinski

mctp i2c: MCTP I2C binding driver

2022-02-19T16:18:49+00:00

Provides MCTP network transport over an I2C bus, as specified in DMTF DSP0237. All messages between nodes are sent as SMBus Block Writes. Each I2C bus to be used for MCTP is flagged in devicetree by a 'mctp-controller' property on the bus node. Each flagged bus gets a mctpi2cX net device created based on the bus number. A 'mctp-i2c-controller' I2C client needs to be added under the adapter. In an I2C mux situation the mctp-i2c-controller node must be attached only to the root I2C bus. The I2C client will handle incoming I2C slave block write data for subordinate busses as well as its own bus. In configurations without devicetree a driver instance can be attached to a bus using the I2C slave new_device mechanism. The MCTP core will hold/release the MCTP I2C device while responses are pending (a 6 second timeout or once a socket is closed, response received etc). While held the MCTP I2C driver will lock the I2C bus so that the correct I2C mux remains selected while responses are received. (Ideally we would just lock the mux to keep the current bus selected for the response rather than a full I2C bus lock, but that isn't exposed in the I2C mux API) Signed-off-by: Matt Johnston Signed-off-by: Jeremy Kerr Reviewed-by: Wolfram Sang # I2C transport parts Signed-off-by: David S. Miller

mctp: serial: Cancel pending work from ndo_uninit handler

2022-02-11T22:39:54+00:00

We cannot do the cancel_work_sync from after the unregister_netdev, as the dev pointer is no longer valid, causing a uaf on ldisc unregister (or device close). Instead, do the cancel_work_sync from the ndo_uninit op, where the dev still exists, but the queue has stopped. Fixes: 7bd9890f3d74 ("mctp: serial: cancel tx work on ldisc close") Reported-by: Luo Likang Tested-by: Luo Likang Signed-off-by: Jeremy Kerr Link: https://lore.kernel.org/r/20220211011552.1861886-1-jk@codeconstruct.com.au Signed-off-by: Jakub Kicinski

mctp: serial: remove unnecessary ldisc data check

2021-11-26T03:40:39+00:00

Jiri assures me that a ldisc->open with tty->disc_data set should never happen, so this check doesn't do anything. Reported-by: Jiri Slaby Signed-off-by: Jeremy Kerr Signed-off-by: Jakub Kicinski

mctp: serial: enforce fixed MTU

2021-11-26T03:40:39+00:00

The current serial driver requires a maximum MTU of 68, and it doesn't make sense to set a MTU below the MCTP-required baseline (of 68) either. This change sets the min_mtu & max_mtu of the mctp netdev, essentially disallowing changes. By using these instead of a ndo_change_mtu op, we get the netlink extacks reported too. Signed-off-by: Jeremy Kerr Signed-off-by: Jakub Kicinski

mctp: serial: cancel tx work on ldisc close

2021-11-26T03:40:39+00:00

We want to ensure that the tx work has finished before returning from the ldisc close op, so do a synchronous cancel. Reported-by: Jiri Slaby Signed-off-by: Jeremy Kerr Signed-off-by: Jakub Kicinski

mctp: Add MCTP-over-serial transport binding

2021-11-23T11:47:51+00:00

This change adds a MCTP Serial transport binding, as defined by DMTF specificiation DSP0253 - "MCTP Serial Transport Binding". This is implemented as a new serial line discipline, and can be attached to arbitrary tty devices. From the Kconfig description: This driver provides an MCTP-over-serial interface, through a serial line-discipline, as defined by DMTF specification "DSP0253 - MCTP Serial Transport Binding". By attaching the ldisc to a serial device, we get a new net device to transport MCTP packets. This allows communication with external MCTP endpoints which use serial as their transport. It can also be used as an easy way to provide MCTP connectivity between virtual machines, by forwarding data between simple virtual serial devices. Say y here if you need to connect to MCTP endpoints over serial. To compile as a module, use m; the module will be called mctp-serial. Once the N_MCTP line discipline is set [using ioctl(TCIOSETD)], we get a new netdev suitable for MCTP communication. The 'mctp' utility[1] provides a simple wrapper for this ioctl, using 'link serial ': # mctp link serial /dev/ttyS0 & # mctp link dev lo index 1 address 0x00:00:00:00:00:00 net 1 mtu 65536 up dev mctpserial0 index 5 address 0x(no-addr) net 1 mtu 68 down [1]: https://github.com/CodeConstruct/mctp Signed-off-by: Jeremy Kerr Signed-off-by: David S. Miller