From: Hou Tao <houtao1@huawei.com>
To: Zhong Jinghua <zhongjinghua@huawei.com>, <axboe@kernel.dk>
Cc: <linux-block@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
<yi.zhang@huawei.com>, <yukuai3@huawei.com>,
<yangerkun@huawei.com>
Subject: Re: [PATCH-next v2] loop: loop_set_status_from_info() check before assignment
Date: Mon, 6 Feb 2023 10:55:47 +0800 [thread overview]
Message-ID: <d9486c88-33b1-3dc1-d58c-89de73679e50@huawei.com> (raw)
In-Reply-To: <20230206020716.2036-1-zhongjinghua@huawei.com>
On 2/6/2023 10:07 AM, Zhong Jinghua wrote:
> In loop_set_status_from_info(), lo->lo_offset and lo->lo_sizelimit should
> be checked before reassignment, because if an overflow error occurs, the
> original correct value will be changed to the wrong value, and it will not
> be changed back.
>
> Modifying to the wrong value logic is always not quiet right, we hope to
> optimize this.
>
> Signed-off-by: Zhong Jinghua <zhongjinghua@huawei.com>
LGTM
> ---
> v1->v2: Modify note: overflowing -> overflow
> drivers/block/loop.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/block/loop.c b/drivers/block/loop.c
> index 1518a6423279..1b35cbd029c7 100644
> --- a/drivers/block/loop.c
> +++ b/drivers/block/loop.c
> @@ -977,13 +977,13 @@ loop_set_status_from_info(struct loop_device *lo,
> return -EINVAL;
> }
>
> + /* Avoid assigning overflow values */
> + if (info->lo_offset > LLONG_MAX || info->lo_sizelimit > LLONG_MAX)
> + return -EOVERFLOW;
> +
> lo->lo_offset = info->lo_offset;
> lo->lo_sizelimit = info->lo_sizelimit;
>
> - /* loff_t vars have been assigned __u64 */
> - if (lo->lo_offset < 0 || lo->lo_sizelimit < 0)
> - return -EOVERFLOW;
> -
> memcpy(lo->lo_file_name, info->lo_file_name, LO_NAME_SIZE);
> lo->lo_file_name[LO_NAME_SIZE-1] = 0;
> lo->lo_flags = info->lo_flags;
next prev parent reply other threads:[~2023-02-06 2:55 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-06 2:07 [PATCH-next v2] loop: loop_set_status_from_info() check before assignment Zhong Jinghua
2023-02-06 2:55 ` Hou Tao [this message]
2023-02-06 3:02 ` Hou Tao
2023-02-06 3:19 ` Yu Kuai
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=d9486c88-33b1-3dc1-d58c-89de73679e50@huawei.com \
--to=houtao1@huawei.com \
--cc=axboe@kernel.dk \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=yangerkun@huawei.com \
--cc=yi.zhang@huawei.com \
--cc=yukuai3@huawei.com \
--cc=zhongjinghua@huawei.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.