Messages in this thread | | | Date | Mon, 1 Dec 2014 13:27:39 +0300 | From | Dan Carpenter <> | Subject | Re: [PATCH] random: add and use memzero_explicit() for clearing data |
| |
On Mon, Aug 25, 2014 at 10:01:39PM +0200, Daniel Borkmann wrote: > zatimend has reported that in his environment (3.16/gcc4.8.3/corei7) > memset() calls which clear out sensitive data in extract_{buf,entropy, > entropy_user}() in random driver are being optimized away by gcc. > > Add a helper memzero_explicit() (similarly as explicit_bzero() variants) > that can be used in such cases where a variable with sensitive data is > being cleared out in the end. Other use cases might also be in crypto > code. [ I have put this into lib/string.c though, as it's always built-in > and doesn't need any dependencies then. ] > > Fixes kernel bugzilla: 82041 >
What???
That's not ok. We totally rely on memset to work. Every single memset that I have added was absolutely necessary. This should be fixed so that memset works instead of adding a work around for specific drivers.
regards, dan carpnter
| |