From: Colin Ian King <colin.king@canonical.com>
To: Andrea Mayer <andrea.mayer@uniroma2.it>
Cc: "David S . Miller" <davem@davemloft.net>,
Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
Jakub Kicinski <kuba@kernel.org>,
netdev@vger.kernel.org, kernel-janitors@vger.kernel.org,
linux-kernel@vger.kernel.org,
Stefano Salsano <stefano.salsano@uniroma2.it>,
Paolo Lungaroni <paolo.lungaroni@cnit.it>,
Ahmed Abdelsalam <ahabdels.dev@gmail.com>
Subject: Re: [PATCH][next] seg6: fix unintentional integer overflow on left shift
Date: Mon, 7 Dec 2020 20:44:09 +0000 [thread overview]
Message-ID: <b969c10e-d5eb-6056-ddcd-9ae70846eb4a@canonical.com> (raw)
In-Reply-To: <20201207205926.6222eca38744c43632248a41@uniroma2.it>
On 07/12/2020 19:59, Andrea Mayer wrote:
> On Mon, 7 Dec 2020 14:45:03 +0000
> Colin King <colin.king@canonical.com> wrote:
>
>> From: Colin Ian King <colin.king@canonical.com>
>>
>> Shifting the integer value 1 is evaluated using 32-bit arithmetic
>> and then used in an expression that expects a unsigned long value
>> leads to a potential integer overflow. Fix this by using the BIT
>> macro to perform the shift to avoid the overflow.
>>
>> Addresses-Coverity: ("Uninitentional integer overflow")
>> Fixes: 964adce526a4 ("seg6: improve management of behavior attributes")
>> Signed-off-by: Colin Ian King <colin.king@canonical.com>
>> ---
>> net/ipv6/seg6_local.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c
>> index b07f7c1c82a4..d68de8cd1207 100644
>> --- a/net/ipv6/seg6_local.c
>> +++ b/net/ipv6/seg6_local.c
>> @@ -1366,7 +1366,7 @@ static void __destroy_attrs(unsigned long parsed_attrs, int max_parsed,
>> * attribute; otherwise, we call the destroy() callback.
>> */
>> for (i = 0; i < max_parsed; ++i) {
>> - if (!(parsed_attrs & (1 << i)))
>> + if (!(parsed_attrs & BIT(i)))
>> continue;
>>
>> param = &seg6_action_params[i];
>> --
>> 2.29.2
>>
>
> Hi Colin,
> thanks for the fix. I've just given a look a the whole seg6_local.c code and I
> found that such issues is present in other parts of the code.
>
> If we agree, I can make a fix which explicitly eliminates the several (1 << i)
> in favor of BIT(i).
Sounds good to me.
Colin
>
> Andrea
>
prev parent reply other threads:[~2020-12-07 20:45 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-07 14:45 [PATCH][next] seg6: fix unintentional integer overflow on left shift Colin King
2020-12-07 19:59 ` Andrea Mayer
2020-12-07 20:44 ` Colin Ian King [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=b969c10e-d5eb-6056-ddcd-9ae70846eb4a@canonical.com \
--to=colin.king@canonical.com \
--cc=ahabdels.dev@gmail.com \
--cc=andrea.mayer@uniroma2.it \
--cc=davem@davemloft.net \
--cc=kernel-janitors@vger.kernel.org \
--cc=kuba@kernel.org \
--cc=kuznet@ms2.inr.ac.ru \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=paolo.lungaroni@cnit.it \
--cc=stefano.salsano@uniroma2.it \
--cc=yoshfuji@linux-ipv6.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).