linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Li Wang <liwang@redhat.com>
To: David Laight <david.laight.linux@gmail.com>
Cc: akpm@linux-foundation.org, linux-kselftest@vger.kernel.org,
	 linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	 David Hildenbrand <david@kernel.org>,
	Mark Brown <broonie@kernel.org>, Shuah Khan <shuah@kernel.org>,
	 Waiman Long <longman@redhat.com>
Subject: Re: [PATCH v3 1/3] selftests/mm/write_to_hugetlbfs: parse -s as size_t
Date: Mon, 22 Dec 2025 09:45:41 +0800	[thread overview]
Message-ID: <CAEemH2f40t+4SsjL3Y=8Gid-CBMtf3eL1egsPKT1J_7LDbdWPQ@mail.gmail.com> (raw)
In-Reply-To: <20251221221052.3b769fc2@pumpkin>

[-- Attachment #1: Type: text/plain, Size: 1025 bytes --]

On Mon, Dec 22, 2025 at 6:11 AM David Laight <david.laight.linux@gmail.com>
wrote:

> On Sun, 21 Dec 2025 20:26:37 +0800
> Li Wang <liwang@redhat.com> wrote:
>
> > write_to_hugetlbfs currently parses the -s size argument with atoi()
> > into an int. This silently accepts malformed input, cannot report
> overflow,
> > and can truncate large sizes.
>
> And sscanf() will just ignore invalid trailing characters.
> Probably much the same as atoi() apart from a leading '-'.
>
> Maybe you could use "%zu%c" and check the count is 1 - but I bet
> some static checker won't like that.
>

Yes, that would be stronger, since it would reject trailing garbage.
But for a selftest this is probably sufficient: switching to size_t and
parsing with "%zu" already avoids the int truncation issue.

@Andrew Morton <akpm@linux-foundation.org>,

Hi Andrew, I noticed you have addedthe patches to your mm-new branch,
Let me know if you prefer the "%zu%c" enhancement in a new version.


-- 
Regards,
Li Wang

[-- Attachment #2: Type: text/html, Size: 2614 bytes --]

  reply	other threads:[~2025-12-22  1:46 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-12-21 12:26 [PATCH v3 0/3] selftests/mm: hugetlb cgroup charging: robustness fixes Li Wang
2025-12-21 12:26 ` [PATCH v3 1/3] selftests/mm/write_to_hugetlbfs: parse -s as size_t Li Wang
2025-12-21 20:23   ` Waiman Long
2025-12-21 22:10   ` David Laight
2025-12-22  1:45     ` Li Wang [this message]
2025-12-22  9:48       ` David Laight
2025-12-22 10:56         ` Li Wang
2025-12-23  2:05           ` Andrew Morton
2025-12-23  2:41             ` Li Wang
2025-12-23  8:40               ` David Laight
2025-12-23  9:29                 ` Li Wang
2025-12-23 12:11                   ` David Laight
2025-12-21 12:26 ` [PATCH v3 2/3] selftests/mm/charge_reserved_hugetlb: drop mount size for hugetlbfs Li Wang
2025-12-21 20:24   ` Waiman Long
2025-12-22 10:01   ` David Hildenbrand (Red Hat)
2025-12-22 19:08     ` Andrew Morton
2025-12-21 12:26 ` [PATCH v3 3/3] selftests/mm/charge_reserved_hugetlb.sh: add waits with timeout helper Li Wang
2025-12-21 20:30   ` Waiman Long
2025-12-22  0:56     ` Li Wang
2025-12-22  3:54       ` Waiman Long
2025-12-22 10:06   ` David Hildenbrand (Red Hat)

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='CAEemH2f40t+4SsjL3Y=8Gid-CBMtf3eL1egsPKT1J_7LDbdWPQ@mail.gmail.com' \
    --to=liwang@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=broonie@kernel.org \
    --cc=david.laight.linux@gmail.com \
    --cc=david@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-kselftest@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=longman@redhat.com \
    --cc=shuah@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