CVE request: kernel: dio: zero struct dio with kzalloc instead of manually

[Eugene Teo <eteo () redhat com>]

Hi Steve,

Is this assigned with a CVE name already? If not, please allocate one.

This upstream commit addressed a user triggerable DoS:
848c4dd5153c7a0de55470ce99a8e13a63b4703f

Summary:
[PATCH] dio: zero struct dio with kzalloc instead of manually

To avoid exposing ourselves to the risk of finding another field like
.map_bh.b_state where we rely on zeroing but don't enforce it in the
code. The fix uses kzalloc to zero all the struct dio rather than
manually trying to track which fields we rely on being zero.

Reproducer:
http://lkml.org/lkml/2007/7/30/448

References:
http://lkml.org/lkml/2007/7/26/88
https://bugzilla.redhat.com/show_bug.cgi?id=461082

Thanks, Eugene
-- 
Eugene Teo / Red Hat Security Response Team