linux-kernel - [PATCH v2] f2fs: add overflow/underflow checks to update_sit

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Message-ID: <CACpam_YTgPkbgh_hHohOmRebJP-J+c8_GKFv6shChddTNk_iDQ@mail.gmail.com>
Date: Thu, 4 Dec 2025 15:05:14 +0800
From: yao xiao <xiangyaof4free@...il.com>
To: Jaegeuk Kim <jaegeuk@...nel.org>, Chao Yu <chao@...nel.org>
Cc: linux-f2fs-devel@...ts.sourceforge.net, linux-fsdevel@...r.kernel.org, 
	linux-kernel@...r.kernel.org
Subject: [PATCH v2] f2fs: add overflow/underflow checks to update_sit_entry— please ignore

Hi,

After re-examining the update_sit_entry() logic and its callers,
I realized that my assumption in the v2 patch was incorrect.

The value of del is strictly bounded in all valid call paths
(either ±1 or -blocks_per_seg), and valid_blocks is already limited
by f2fs_usable_blks_in_seg().
Therefore the arithmetic cannot overflow before the existing
f2fs_bug_on() range check is executed.

As a result, the overflow/underflow checks introduced in my patch are
unnecessary.
Please ignore this patch.

Sorry for the noise, and thank you for your time.

Best regards,
Yao Xiao