From: "Jason A. Donenfeld" <ja...@zx2c4.com> Date: Mon, 9 Oct 2017 14:14:51 +0200
> It turns out that multiple places can call netlink_dump(), which means > it's still possible to dereference partially initialized values in > dump() that were the result of a faulty returned start(). > > This fixes the issue by calling start() _before_ setting cb_running to > true, so that there's no chance at all of hitting the dump() function > through any indirect paths. > > It also moves the call to start() to be when the mutex is held. This has > the nice side effect of serializing invocations to start(), which is > likely desirable anyway. It also prevents any possible other races that > might come out of this logic. > > In testing this with several different pieces of tricky code to trigger > these issues, this commit fixes all avenues that I'm aware of. > > Signed-off-by: Jason A. Donenfeld <ja...@zx2c4.com> Applied and queued up for -stable.
