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Date:   Fri, 7 Aug 2020 08:47:29 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     linux-kernel@vger.kernel.org, kernel test robot <lkp@intel.com>,
        stable@vger.kernel.org, Jessica Yu <jeyu@kernel.org>,
        Shuah Khan <shuah@kernel.org>,
        Masahiro Yamada <masahiroy@kernel.org>,
        linux-kselftest@vger.kernel.org
Subject: Re: [PATCH 1/2] module: Correctly truncate sysfs sections output
Message-ID: <20200807064729.GA981993@kroah.com>
References: <20200807063539.2620154-1-keescook@chromium.org>
 <20200807063539.2620154-2-keescook@chromium.org>
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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@linuxfoundation.org>