Re: [PATCH] fix infoleak in fcntl

[Richard Weinberger]

Am 08.05.2016 um 17:40 schrieb Kangjie Lu:
> 
> 
> On Sun, May 8, 2016 at 8:58 AM, Richard Weinberger <richard.weinberger@xxxxxxxxx <mailto:richard.weinberger@xxxxxxxxx>> wrote:
> 
>     On Tue, May 3, 2016 at 10:34 PM, Kangjie Lu <kangjielu@xxxxxxxxx <mailto:kangjielu@xxxxxxxxx>> wrote:
>     > The stack object âsiâ has a total size of 128 bytes; however, only
>     > 16 bytes are initialized. The remaining uninitialized bytes are
>     > sent to userland via send_signal.
> 
>     How did you find all these leaks?
>     Since you sent more than one patch I guess you used some tool, which one?
> 
> 
> Yes. Since there are *so many* infoleak vulnerabilities in the kernel, we are writing a
> static checker to find them.  We plan to release it once it is done, so people can use
> it to find more bugs in kernel or even other user space programs.

How does your tool work?
I'd guess it tries to find uninitialized structs passed into copy_to_user().

Thanks,
//richard