kernel/linux.git/drivers/net/netconsole.c, branch v6.1.168

net: netconsole: Disable target before netpoll cleanup

2024-08-03T06:49:30+00:00

commit 97d9fba9a812cada5484667a46e14a4c976ca330 upstream. Currently, netconsole cleans up the netpoll structure before disabling the target. This approach can lead to race conditions, as message senders (write_ext_msg() and write_msg()) check if the target is enabled before using netpoll. The sender can validate that the target is enabled, but, the netpoll might be de-allocated already, causing undesired behaviours. This patch reverses the order of operations: 1. Disable the target 2. Clean up the netpoll structure This change eliminates the potential race condition, ensuring that no messages are sent through a partially cleaned-up netpoll structure. Fixes: 2382b15bcc39 ("netconsole: take care of NETDEV_UNREGISTER event") Cc: stable@vger.kernel.org Signed-off-by: Breno Leitao Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20240712143415.1141039-1-leitao@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: move from strlcpy with unused retval to strscpy

2022-08-31T21:11:07+00:00

Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang Acked-by: Marc Kleine-Budde # for CAN Link: https://lore.kernel.org/r/20220830201457.7984-1-wsa+renesas@sang-engineering.com Signed-off-by: Jakub Kicinski

net: rename reference+tracking helpers

2022-06-10T04:52:55+00:00

Netdev reference helpers have a dev_ prefix for historic reasons. Renaming the old helpers would be too much churn but we can rename the tracking ones which are relatively recent and should be the default for new code. Rename: dev_hold_track() -> netdev_hold() dev_put_track() -> netdev_put() dev_replace_track() -> netdev_ref_replace() Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

netpoll: add net device refcount tracker to struct netpoll

2021-12-07T00:06:02+00:00

Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski

net: netconsole: Add description for 'netconsole_target's extended attribute

2020-11-04T00:40:09+00:00

Fixes the following W=1 kernel build warning(s): drivers/net/netconsole.c:104: warning: Function parameter or member 'extended' not described in 'netconsole_target' Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20201102114512.1062724-29-lee.jones@linaro.org Signed-off-by: Jakub Kicinski

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 675 mass ave cambridge ma 02139 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 77 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Armijn Hemel Reviewed-by: Richard Fontana Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.837555891@linutronix.de Signed-off-by: Greg Kroah-Hartman

netconsole: make config_item_type const

2017-10-19T14:15:20+00:00

Make these structures const as they are either passed to the functions having the argument as const or stored as a reference in the "ci_type" const field of a config_item structure. Done using Coccienlle. Signed-off-by: Bhumika Goyal Signed-off-by: Christoph Hellwig

netconsole: Remove duplicate "netconsole: " logging prefix

2017-06-13T16:57:40+00:00

It's already added by pr_fmt so remove the explicit use. Signed-off-by: Joe Perches Signed-off-by: David S. Miller

netconsole: use per-attribute show and store methods

2015-10-14T05:17:51+00:00

Note that the old code actually used the store_attributes method to do locking, this is moved into the individual methods. Signed-off-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger

netconsole: implement extended console support

2015-06-26T00:00:39+00:00

printk logbuf keeps various metadata and optional key=value dictionary for structured messages, both of which are stripped when messages are handed to regular console drivers. It can be useful to have this metadata and dictionary available to netconsole consumers. This obviously makes logging via netconsole more complete and the sequence number in particular is useful in environments where messages may be lost or reordered in transit - e.g. when netconsole is used to collect messages in a large cluster where packets may have to travel congested hops to reach the aggregator. The lost and reordered messages can easily be identified and handled accordingly using the sequence numbers. printk recently added extended console support which can be selected by setting CON_EXTENDED flag. From console driver side, not much changes. The only difference is that the text passed to the write callback is formatted the same way as /dev/kmsg. This patch implements extended console support for netconsole which can be enabled by either prepending "+" to a netconsole boot param entry or echoing 1 to "extended" file in configfs. When enabled, netconsole transmits extended log messages with headers identical to /dev/kmsg output. There's one complication due to message fragments. netconsole limits the maximum message size to 1k and messages longer than that are split into multiple fragments. As all extended console messages should carry matching headers and be uniquely identifiable, each extended message fragment carries full copy of the metadata and an extra header field to identify the specific fragment. The optional header is of the form "ncfrag=OFF/LEN" where OFF is the byte offset into the message body and LEN is the total length. To avoid unnecessarily making printk format extended messages, Extended netconsole is registered with printk when the first extended netconsole is configured. Signed-off-by: Tejun Heo Cc: David Miller Cc: Kay Sievers Cc: Petr Mladek Cc: Tetsuo Handa Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds