kernel/git/stable/linux.git/net/ax25/ax25_subr.c, branch master

net: remove ax25 and amateur radio (hamradio) subsystem

2026-04-23T17:24:02+00:00

Remove the amateur radio (AX.25, NET/ROM, ROSE) protocol implementation and all associated hamradio device drivers from the kernel tree. This set of protocols has long been a huge bug/syzbot magnet, and since nobody stepped up to help us deal with the influx of the AI-generated bug reports we need to move it out of tree to protect our sanity. The code is moved to an out-of-tree repo: https://github.com/linux-netdev/mod-orphan if it's cleaned up and reworked there we can accept it back. Minimal stub headers are kept for include/net/ax25.h (AX25_P_IP, AX25_ADDR_LEN, ax25_address) and include/net/rose.h (ROSE_ADDR_LEN) so that the conditional integration code in arp.c and tun.c continues to compile and work when the out-of-tree modules are loaded. Signed-off-by: Jakub Kicinski Acked-by: Greg Kroah-Hartman Acked-by: Stephen Hemminger Acked-by: Carlos Bilbao Reviewed-by: Simon Horman Reviewed-by: Kuniyuki Iwashima Acked-by: Toke Høiland-Jørgensen Link: https://patch.msgid.link/20260421021824.1293976-1-kuba@kernel.org Signed-off-by: Paolo Abeni

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12+00:00

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar

ax25: Fix ax25 session cleanup problems

2022-06-02T08:37:57+00:00

There are session cleanup problems in ax25_release() and ax25_disconnect(). If we setup a session and then disconnect, the disconnected session is still in "LISTENING" state that is shown below. Active AX.25 sockets Dest Source Device State Vr/Vs Send-Q Recv-Q DL9SAU-4 DL9SAU-3 ??? LISTENING 000/000 0 0 DL9SAU-3 DL9SAU-4 ??? LISTENING 000/000 0 0 The first reason is caused by del_timer_sync() in ax25_release(). The timers of ax25 are used for correct session cleanup. If we use ax25_release() to close ax25 sessions and ax25_dev is not null, the del_timer_sync() functions in ax25_release() will execute. As a result, the sessions could not be cleaned up correctly, because the timers have stopped. In order to solve this problem, this patch adds a device_up flag in ax25_dev in order to judge whether the device is up. If there are sessions to be cleaned up, the del_timer_sync() in ax25_release() will not execute. What's more, we add ax25_cb_del() in ax25_kill_by_device(), because the timers have been stopped and there are no functions that could delete ax25_cb if we do not call ax25_release(). Finally, we reorder the position of ax25_list_lock in ax25_cb_del() in order to synchronize among different functions that call ax25_cb_del(). The second reason is caused by improper check in ax25_disconnect(). The incoming ax25 sessions which ax25->sk is null will close heartbeat timer, because the check "if(!ax25->sk || ..)" is satisfied. As a result, the session could not be cleaned up properly. In order to solve this problem, this patch changes the improper check to "if(ax25->sk && ..)" in ax25_disconnect(). What`s more, the ax25_disconnect() may be called twice, which is not necessary. For example, ax25_kill_by_device() calls ax25_disconnect() and sets ax25->state to AX25_STATE_0, but ax25_release() calls ax25_disconnect() again. In order to solve this problem, this patch add a check in ax25_release(). If the flag of ax25->sk equals to SOCK_DEAD, the ax25_disconnect() in ax25_release() should not be executed. Fixes: 82e31755e55f ("ax25: Fix UAF bugs in ax25 timers") Fixes: 8a367e74c012 ("ax25: Fix segfault after sock connection timeout") Reported-and-tested-by: Thomas Osterried Signed-off-by: Duoming Zhou Link: https://lore.kernel.org/r/20220530152158.108619-1-duoming@zju.edu.cn Signed-off-by: Paolo Abeni

ax25: Fix NULL pointer dereferences in ax25 timers

2022-03-21T10:56:19+00:00

The previous commit 7ec02f5ac8a5 ("ax25: fix NPD bug in ax25_disconnect") move ax25_disconnect into lock_sock() in order to prevent NPD bugs. But there are race conditions that may lead to null pointer dereferences in ax25_heartbeat_expiry(), ax25_t1timer_expiry(), ax25_t2timer_expiry(), ax25_t3timer_expiry() and ax25_idletimer_expiry(), when we use ax25_kill_by_device() to detach the ax25 device. One of the race conditions that cause null pointer dereferences can be shown as below: (Thread 1) | (Thread 2) ax25_connect() | ax25_std_establish_data_link() | ax25_start_t1timer() | mod_timer(&ax25->t1timer,..) | | ax25_kill_by_device() (wait a time) | ... | s->ax25_dev = NULL; //(1) ax25_t1timer_expiry() | ax25->ax25_dev->values[..] //(2)| ... ... | We set null to ax25_cb->ax25_dev in position (1) and dereference the null pointer in position (2). The corresponding fail log is shown below: =============================================================== BUG: kernel NULL pointer dereference, address: 0000000000000050 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.17.0-rc6-00794-g45690b7d0 RIP: 0010:ax25_t1timer_expiry+0x12/0x40 ... Call Trace: call_timer_fn+0x21/0x120 __run_timers.part.0+0x1ca/0x250 run_timer_softirq+0x2c/0x60 __do_softirq+0xef/0x2f3 irq_exit_rcu+0xb6/0x100 sysvec_apic_timer_interrupt+0xa2/0xd0 ... This patch moves ax25_disconnect() before s->ax25_dev = NULL and uses del_timer_sync() to delete timers in ax25_disconnect(). If ax25_disconnect() is called by ax25_kill_by_device() or ax25->ax25_dev is NULL, the reason in ax25_disconnect() will be equal to ENETUNREACH, it will wait all timers to stop before we set null to s->ax25_dev in ax25_kill_by_device(). Fixes: 7ec02f5ac8a5 ("ax25: fix NPD bug in ax25_disconnect") Signed-off-by: Duoming Zhou Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

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 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

ax25: Fix segfault after sock connection timeout

2017-01-16T19:39:58+00:00

The ax.25 socket connection timed out & the sock struct has been previously taken down ie. sock struct is now a NULL pointer. Checking the sock_flag causes the segfault. Check if the socket struct pointer is NULL before checking sock_flag. This segfault is seen in timed out netrom connections. Please submit to -stable. Signed-off-by: Basil Gunn Signed-off-by: David S. Miller

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*' sed -i -e "s!$PATT!#include !" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro Signed-off-by: Linus Torvalds

AX.25: Close socket connection on session completion

2016-06-19T03:55:34+00:00

A socket connection made in ax.25 is not closed when session is completed. The heartbeat timer is stopped prematurely and this is where the socket gets closed. Allow heatbeat timer to run to close socket. Symptom occurs in kernels >= 4.2.0 Originally sent 6/15/2016. Resend with distribution list matching scripts/maintainer.pl output. Signed-off-by: Basil Gunn Signed-off-by: David S. Miller

NET: AX.25: Stop heartbeat timer on disconnect.

2015-07-15T22:59:58+00:00

This may result in a kernel panic. The bug has always existed but somehow we've run out of luck now and it bites. Signed-off-by: Richard Stearn Cc: stable@vger.kernel.org # all branches Signed-off-by: Ralf Baechle Signed-off-by: David S. Miller

Remove all #inclusions of asm/system.h

2012-03-28T17:30:03+00:00

Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*.*\n!!' `grep -Irl '^#\s*include\s*' *` Signed-off-by: David Howells