From: Sergey Senozhatsky <senozhatsky@chromium.org>
To: Longlong Xia <xialonglong2025@163.com>,
Andrew Morton <akpm@linux-foundation.org>
Cc: minchan@kernel.org, senozhatsky@chromium.org, axboe@kernel.dk,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
stable@vger.kernel.org, Longlong Xia <xialonglong@kylinos.cn>
Subject: Re: [PATCH 1/1] zram: reject disksizes that exceed slot index range
Date: Wed, 5 Aug 2026 10:28:14 +0900 [thread overview]
Message-ID: <anKRhIPsWUwvCzm_@google.com> (raw)
In-Reply-To: <20260804143832.146129-1-xialonglong2025@163.com>
On (26/08/04 22:38), Longlong Xia wrote:
> zram uses u32 slot indexes, while disksize_store() accepts a u64
> size. On 32-bit systems, a disksize larger than U32_MAX pages is
> truncated when zram_meta_alloc() assigns the page count to size_t.
> array_size() then sees only the truncated count, so a small table can
> be allocated while the original capacity is published. Valid I/O
> within that capacity can subsequently access beyond zram->table.
>
> The same oversized capacity also lets full-device scanners compare a
> u32 index with an upper bound larger than U32_MAX, so the index can
> wrap instead of terminating.
>
> Reject disksizes larger than U32_MAX pages before aligning and
> allocating the table. This keeps the table size, published capacity and
> slot index range consistent.
>
> Fixes: 33863c21e69e ("Staging: zram: Replace ioctls with sysfs interface")
> Cc: <stable@vger.kernel.org>
> Assisted-by: Codex:gpt-5.6-sol
> Signed-off-by: Longlong Xia <xialonglong@kylinos.cn>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
next prev parent reply other threads:[~2026-08-05 1:28 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-04 14:38 [PATCH 1/1] zram: reject disksizes that exceed slot index range Longlong Xia
2026-08-05 1:28 ` Sergey Senozhatsky [this message]
2026-08-05 18:54 ` Andrew Morton
2026-08-06 2:41 ` Sergey Senozhatsky
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=anKRhIPsWUwvCzm_@google.com \
--to=senozhatsky@chromium.org \
--cc=akpm@linux-foundation.org \
--cc=axboe@kernel.dk \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=minchan@kernel.org \
--cc=stable@vger.kernel.org \
--cc=xialonglong2025@163.com \
--cc=xialonglong@kylinos.cn \
/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.