tree d3f5f15e9840964657bf40326705d79abe06e9e1
parent 5ccdcecb72692d46d7a9264e62751241c7eca559
author Michal Ostrowski <mostrows@gmail.com> 1256599400 -0700
committer David S. Miller <davem@davemloft.net> 1256599400 -0700

PPPoE: Fix flush/close races.

Be more careful about the state of pointers during tear-down.
The "pppoe_dev" field can only be looked at safely while holding socket locks.
This subsequently allows for the flush_lock to be killed.

We depend on the PPPOX_CONNECTED state to tell us that that those fields are
valid, so whoever clears that state (pppox_unbind_sock()) is responsible for
the dev_put() call.

We also have to ensure that we delete_item() on all sockets before they are
cleaned up.

The need for these changes has been exposed by scenarios wherein namespace
bindings of ethernet devices change while there are ongoing PPPoE sessions,
which resulted in oopses due to unusual socket connection termination paths,
exposing these issues.

Signed-off-by: Michal Ostrowski <mostrows@gmail.com>
Reviewed-by: Cyril Gorcunov <gorcunov@gmail.com>
Reported-by: Denys Fedoryschenko <denys@visp.net.lb>
Tested-by: Denys Fedoryschenko <denys@visp.net.lb>