From: Brian Masney <bmasney@redhat.com>
To: david.laight.linux@gmail.com
Cc: Christian Brauner <brauner@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Miklos Szeredi <miklos@szeredi.hu>,
Mark Brown <broonie@kernel.org>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
Alexander Viro <viro@zeniv.linux.org.uk>,
Andreas Dilger <adilger.kernel@dilger.ca>,
Kees Cook <kees@kernel.org>,
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>,
Theodore Ts'o <tytso@mit.edu>
Subject: Re: [PATCH next] fuse: Fix 'min: signedness error' in fuse_wr_pages()
Date: Tue, 13 Jan 2026 15:23:19 -0500 [thread overview]
Message-ID: <aWapt9vh8EEGdFUG@redhat.com> (raw)
In-Reply-To: <20260113192243.73983-1-david.laight.linux@gmail.com>
On Tue, Jan 13, 2026 at 07:22:43PM +0000, david.laight.linux@gmail.com wrote:
> From: David Laight <david.laight.linux@gmail.com>
>
> On 32bit systems 'pos' is s64 and everything else is 32bit so the
> first argument to min() is signed - generating a warning.
> On 64bit systems 'len' is 64bit unsigned forcing everything to unsigned.
>
> Fix by reworking the exprssion to completely avoid 64bit maths on 32bit.
> Use DIV_ROUND_UP() instead of open-coding something equivalent.
>
> Note that the 32bit 'len' cannot overflow because the syscall interface
> limits read/write (etc) to (INT_MAX - PAGE_SIZE) bytes (even on 64bit).
>
> Fixes: 0f5bb0cfb0b4 ("fs: use min() or umin() instead of min_t()")
> Signed-off-by: David Laight <david.laight.linux@gmail.com>
Reported-by: Brian Masney <bmasney@redhat.com>
Reviewed-by: Brian Masney <bmasney@redhat.com>
This fixes the MIPS cross compiler error on arm64 that I reported. I
also tested a native arm64 build.
Brian
next prev parent reply other threads:[~2026-01-13 20:23 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-13 19:22 [PATCH next] fuse: Fix 'min: signedness error' in fuse_wr_pages() david.laight.linux
2026-01-13 20:23 ` Brian Masney [this message]
2026-02-03 1:05 ` Nathan Chancellor
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=aWapt9vh8EEGdFUG@redhat.com \
--to=bmasney@redhat.com \
--cc=adilger.kernel@dilger.ca \
--cc=akpm@linux-foundation.org \
--cc=brauner@kernel.org \
--cc=broonie@kernel.org \
--cc=david.laight.linux@gmail.com \
--cc=hirofumi@mail.parknet.co.jp \
--cc=kees@kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=miklos@szeredi.hu \
--cc=tytso@mit.edu \
--cc=viro@zeniv.linux.org.uk \
/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