[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20221122133908.422677-1-alexandr.lobakin@intel.com>
Date: Tue, 22 Nov 2022 14:39:08 +0100
From: Alexander Lobakin <alexandr.lobakin@...el.com>
To: Maxim Korotkov <korotkov.maxim.s@...il.com>
Cc: Alexander Lobakin <alexandr.lobakin@...el.com>,
"David S. Miller" <davem@...emloft.net>,
Eric Dumazet <edumazet@...gle.com>,
Jakub Kicinski <kuba@...nel.org>,
Paolo Abeni <pabeni@...hat.com>,
Guangbin Huang <huangguangbin2@...wei.com>,
Andrew Lunn <andrew@...n.ch>,
"Keller, Jacob E" <jacob.e.keller@...el.com>,
Tom Rix <trix@...hat.com>, Marco Bonelli <marco@...eim.net>,
Edward Cree <ecree@...arflare.com>, netdev@...r.kernel.org,
linux-kernel@...r.kernel.org, lvc-project@...uxtesting.org
Subject: Re: [PATCH v3] ethtool: avoiding integer overflow in ethtool_phys_id()
From: Maxim Korotkov <korotkov.maxim.s@...il.com>
Date: Tue, 22 Nov 2022 15:29:01 +0300
> The value of an arithmetic expression "n * id.data" is subject
> to possible overflow due to a failure to cast operands to a larger data
> type before performing arithmetic. Used macro for multiplication instead
> operator for avoiding overflow.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Signed-off-by: Maxim Korotkov <korotkov.maxim.s@...il.com>
Reviewed-by: Alexander Lobakin <alexandr.lobakin@...el.com>
> ---
> net/ethtool/ioctl.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
> index 6a7308de192d..6b59e7a1c906 100644
> --- a/net/ethtool/ioctl.c
> +++ b/net/ethtool/ioctl.c
> @@ -2007,7 +2007,8 @@ static int ethtool_phys_id(struct net_device *dev, void __user *useraddr)
> } else {
> /* Driver expects to be called at twice the frequency in rc */
> int n = rc * 2, interval = HZ / n;
> - u64 count = n * id.data, i = 0;
> + u64 count = mul_u32_u32(n, id.data);
> + u64 i = 0;
>
> do {
> rtnl_lock();
> --
> 2.17.1
Some notes to the process, not the code:
1) I asked to add my Reviewed-by to v3 in the previous thread, it's
mandatory for authors to pick-up all the tags before publishing
a new revision;
2) when sending v2, v3, ... vN, please have a changelog in the
commit message or right below those '---' after your SoB, that
makes it easier to review.
Thanks,
Olek
Powered by blists - more mailing lists