Re: [PATCH 1/2] module: Correctly truncate sysfs sections output

From: Greg Kroah-Hartman
Date: Fri Aug 07 2020 - 02:47:35 EST

On Thu, Aug 06, 2020 at 11:35:38PM -0700, Kees Cook wrote:
> The only-root-readable /sys/module/$module/sections/$section files
> did not truncate their output to the available buffer size. While most
> paths into the kernfs read handlers end up using PAGE_SIZE buffers,
> it's possible to get there through other paths (e.g. splice, sendfile).
> Actually limit the output to the "count" passed into the read function,
> and report it back correctly. *sigh*

Ugh, never thought about that...

Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>