mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-06 10:58:48 +09:00
7eb5dd2016
commit ccb7276a6d26d6f8416e315b43b45e15ee7f29e2 upstream.
Reference counting is used to ensure that
batadv_hardif_neigh_node and batadv_hard_iface
are not freed before/during
batadv_v_elp_throughput_metric_update work is
finished.
But there isn't a guarantee that the hard if will
remain associated with a soft interface up until
the work is finished.
This fixes a crash triggered by reboot that looks
like this:
Call trace:
batadv_v_mesh_free+0xd0/0x4dc [batman_adv]
batadv_v_elp_throughput_metric_update+0x1c/0xa4
process_one_work+0x178/0x398
worker_thread+0x2e8/0x4d0
kthread+0xd8/0xdc
ret_from_fork+0x10/0x20
(the batadv_v_mesh_free call is misleading,
and does not actually happen)
I was able to make the issue happen more reliably
by changing hardif_neigh->bat_v.metric_work work
to be delayed work. This allowed me to track down
and confirm the fix.
Cc: stable@vger.kernel.org
Fixes: c833484e5f ("batman-adv: ELP - compute the metric based on the estimated throughput")
Signed-off-by: Andy Strohman <andrew@andrewstrohman.com>
[sven@narfation.org: prevent entering batadv_v_elp_get_throughput without
soft_iface]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.