diff options
| author | Sven Eckelmann <sven@narfation.org> | 2018-12-30 14:46:01 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-20 12:09:09 +0300 |
| commit | 863938b84c4b2c34623c76dd838014e011951ccc (patch) | |
| tree | e70cc47971cff33245dba6c3623be7c1dee0ed48 | |
| parent | 98af4f7e3377fa73a6aaa8872b111d9cf03570bb (diff) | |
| download | linux-863938b84c4b2c34623c76dd838014e011951ccc.tar.xz | |
batman-adv: Avoid WARN on net_device without parent in netns
commit 955d3411a17f590364238bd0d3329b61f20c1cd2 upstream.
It is not allowed to use WARN* helpers on potential incorrect input from
the user or transient problems because systems configured as panic_on_warn
will reboot due to such a problem.
A NULL return value of __dev_get_by_index can be caused by various problems
which can either be related to the system configuration or problems
(incorrectly returned network namespaces) in other (virtual) net_device
drivers. batman-adv should not cause a (harmful) WARN in this situation and
instead only report it via a simple message.
Fixes: b7eddd0b3950 ("batman-adv: prevent using any virtual device created on batman-adv as hard-interface")
Reported-by: syzbot+c764de0fcfadca9a8595@syzkaller.appspotmail.com
Reported-by: Dmitry Vyukov <dvyukov@google.com>
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>
| -rw-r--r-- | net/batman-adv/hard-interface.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index fbda6b54baff..51f060df64ef 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -89,8 +89,10 @@ static bool batadv_is_on_batman_iface(const struct net_device *net_dev) /* recurse over the parent device */ parent_dev = __dev_get_by_index(&init_net, net_dev->iflink); /* if we got a NULL parent_dev there is something broken.. */ - if (WARN(!parent_dev, "Cannot find parent device")) + if (!parent_dev) { + pr_err("Cannot find parent device\n"); return false; + } ret = batadv_is_on_batman_iface(parent_dev); |