diff options
| author | Andy Strohman <andrew@andrewstrohman.com> | 2025-01-09 02:27:56 +0000 |
|---|---|---|
| committer | Simon Wunderlich <sw@simonwunderlich.de> | 2025-01-19 22:10:20 +0100 |
| commit | ccb7276a6d26d6f8416e315b43b45e15ee7f29e2 (patch) | |
| tree | 89e71f5264c68e92d684935d413a7bf03595b129 | |
| parent | fff8f17c1a6fc802ca23bbd3a276abfde8cc58e6 (diff) | |
batman-adv: fix panic during interface removal
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: c833484e5f38 ("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>
| -rw-r--r-- | net/batman-adv/bat_v_elp.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c index 1d704574e6bf..fbf499bcc671 100644 --- a/net/batman-adv/bat_v_elp.c +++ b/net/batman-adv/bat_v_elp.c @@ -66,12 +66,19 @@ static void batadv_v_elp_start_timer(struct batadv_hard_iface *hard_iface) static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh) { struct batadv_hard_iface *hard_iface = neigh->if_incoming; + struct net_device *soft_iface = hard_iface->soft_iface; struct ethtool_link_ksettings link_settings; struct net_device *real_netdev; struct station_info sinfo; u32 throughput; int ret; + /* don't query throughput when no longer associated with any + * batman-adv interface + */ + if (!soft_iface) + return BATADV_THROUGHPUT_DEFAULT_VALUE; + /* if the user specified a customised value for this interface, then * return it directly */ @@ -141,7 +148,7 @@ static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh) default_throughput: if (!(hard_iface->bat_v.flags & BATADV_WARNING_DEFAULT)) { - batadv_info(hard_iface->soft_iface, + batadv_info(soft_iface, "WiFi driver or ethtool info does not provide information about link speeds on interface %s, therefore defaulting to hardcoded throughput values of %u.%1u Mbps. Consider overriding the throughput manually or checking your driver.\n", hard_iface->net_dev->name, BATADV_THROUGHPUT_DEFAULT_VALUE / 10, |