diff options
| author | Eric Dumazet <edumazet@google.com> | 2018-03-05 08:51:03 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-31 18:12:34 +0200 |
| commit | 41462e8f610c3b0056e89fbc2a2d1b37416466aa (patch) | |
| tree | 083405db847139d780f4271fc3fbe4e931c45c97 | |
| parent | bd01dd8b1036a6d55247e0a04a09e376c6d4bd9a (diff) | |
ieee802154: 6lowpan: fix possible NULL deref in lowpan_device_event()
[ Upstream commit ca0edb131bdf1e6beaeb2b8289fd6b374b74147d ]
A tun device type can trivially be set to arbitrary value using
TUNSETLINK ioctl().
Therefore, lowpan_device_event() must really check that ieee802154_ptr
is not NULL.
Fixes: 2c88b5283f60d ("ieee802154: 6lowpan: remove check on null")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Stefan Schmidt <stefan@osg.samsung.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/ieee802154/6lowpan/core.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/net/ieee802154/6lowpan/core.c b/net/ieee802154/6lowpan/core.c index 20c49c724ba0..e8b279443d37 100644 --- a/net/ieee802154/6lowpan/core.c +++ b/net/ieee802154/6lowpan/core.c @@ -206,9 +206,13 @@ static inline void lowpan_netlink_fini(void) static int lowpan_device_event(struct notifier_block *unused, unsigned long event, void *ptr) { - struct net_device *wdev = netdev_notifier_info_to_dev(ptr); + struct net_device *ndev = netdev_notifier_info_to_dev(ptr); + struct wpan_dev *wpan_dev; - if (wdev->type != ARPHRD_IEEE802154) + if (ndev->type != ARPHRD_IEEE802154) + return NOTIFY_DONE; + wpan_dev = ndev->ieee802154_ptr; + if (!wpan_dev) goto out; switch (event) { @@ -217,8 +221,8 @@ static int lowpan_device_event(struct notifier_block *unused, * also delete possible lowpan interfaces which belongs * to the wpan interface. */ - if (wdev->ieee802154_ptr->lowpan_dev) - lowpan_dellink(wdev->ieee802154_ptr->lowpan_dev, NULL); + if (wpan_dev->lowpan_dev) + lowpan_dellink(wpan_dev->lowpan_dev, NULL); break; default: break; |