Re: [PATCH] kernel/sysctl.c: fix out of bounds access in fs.file-max

From: Matteo Croce
Date: Wed Apr 03 2019 - 07:55:36 EST

On Thu, Mar 28, 2019 at 2:03 PM Matteo Croce <mcroce@xxxxxxxxxx> wrote:
> fs.file-max sysctl uses proc_doulongvec_minmax() as proc handler, which
> accesses *extra1 and *extra2 as unsigned long, but commit 32a5ad9c2285
> ("sysctl: handle overflow for file-max") assigns &zero, which is an int,
> to extra1, generating the following KASAN report.
> Fix this by changing 'zero' to long, which does not need to be duplicated
> like 'one' and 'one_ul' for two data types.


Anyone looked at this patch? Does my fix looks sane?

Matteo Croce
per aspera ad upstream