On Fri, Jul 18, 2014 at 03:16:18PM +0200, Arnd Bergmann wrote: > On Friday 18 July 2014 08:56:06 Theodore Ts'o wrote: > > > > The change in the v3 version of the commit was to eliminate potential > > short reads and EINTR returns when reading from urandom (once the > > urandom pool is initialized). This was based on comments and requests > > from Theo de Raadt. See the NOTES section in the suggested man page for > > a more in-depth discussion of the issues involved. > > I think there is a problem with the completion... > > However, here you can get called an arbitrary number of times. > It seems entirely possible than an attacker can manage to call > this function 2 billion times. Assuming a latency of 1 microsecond > per syscall, that would take about half an hour. After that, you > never again get any urandom data out of the syscall. > > I think you are better off using a plain wait_event() here. Nice catch, thanks!! I'll rework the patch to use wait_event(). - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
