netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Johannes Berg <johannes@sipsolutions.net>
To: Colin King <colin.king@canonical.com>,
	"David S . Miller" <davem@davemloft.net>,
	linux-wireless@vger.kernel.org, netdev@vger.kernel.org
Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mac80211: ethtool: avoid 32 bit multiplication overflow
Date: Tue, 08 May 2018 15:01:20 +0200	[thread overview]
Message-ID: <1525784480.14830.12.camel@sipsolutions.net> (raw)
In-Reply-To: <20180508125732.5153-1-colin.king@canonical.com>

On Tue, 2018-05-08 at 13:57 +0100, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> The multiplication of 100000 * cfg80211_calculate_bitrate() is a 32 bit
> operation and can overflow if cfg80211_calculate_bitrate is greater
> than 42949. Although I don't believe this is occurring at present, it
> would be safer to avoid the potential overflow by making the constant
> 100000 an ULL to ensure a 64 multiplication occurs.

Yeah it can't happen since mac80211 doesn't support 60 GHz devices, and
all others are limited to less than than.

Still, applied.

johannes

      reply	other threads:[~2018-05-08 13:01 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-08 12:57 [PATCH] mac80211: ethtool: avoid 32 bit multiplication overflow Colin King
2018-05-08 13:01 ` Johannes Berg [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1525784480.14830.12.camel@sipsolutions.net \
    --to=johannes@sipsolutions.net \
    --cc=colin.king@canonical.com \
    --cc=davem@davemloft.net \
    --cc=kernel-janitors@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-wireless@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).