diff options
| author | Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi> | 2020-06-21 13:43:26 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-06-22 16:34:31 -0700 |
| commit | b835a71ef64a61383c414d6bf2896d2c0161deca (patch) | |
| tree | 47baa98d5f2391248c50c4eef2f30ef6e30d79f5 | |
| parent | f3fe412b0a634286a6a3753c3f9ff201e6bec716 (diff) | |
usbnet: smsc95xx: Fix use-after-free after removal
Syzbot reports an use-after-free in workqueue context:
BUG: KASAN: use-after-free in mutex_unlock+0x19/0x40 kernel/locking/mutex.c:737
mutex_unlock+0x19/0x40 kernel/locking/mutex.c:737
__smsc95xx_mdio_read drivers/net/usb/smsc95xx.c:217 [inline]
smsc95xx_mdio_read+0x583/0x870 drivers/net/usb/smsc95xx.c:278
check_carrier+0xd1/0x2e0 drivers/net/usb/smsc95xx.c:644
process_one_work+0x777/0xf90 kernel/workqueue.c:2274
worker_thread+0xa8f/0x1430 kernel/workqueue.c:2420
kthread+0x2df/0x300 kernel/kthread.c:255
It looks like that smsc95xx_unbind() is freeing the structures that are
still in use by the concurrently running workqueue callback. Thus switch
to using cancel_delayed_work_sync() to ensure the work callback really
is no longer active.
Reported-by: syzbot+29dc7d4ae19b703ff947@syzkaller.appspotmail.com
Signed-off-by: Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/usb/smsc95xx.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index 355be77f4241..3cf4dc3433f9 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -1324,7 +1324,7 @@ static void smsc95xx_unbind(struct usbnet *dev, struct usb_interface *intf) struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]); if (pdata) { - cancel_delayed_work(&pdata->carrier_check); + cancel_delayed_work_sync(&pdata->carrier_check); netif_dbg(dev, ifdown, dev->net, "free pdata\n"); kfree(pdata); pdata = NULL; |