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Date: Sun, 28 Jun 2026 13:27:10 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Ren Wei <n05ec@lzu.edu.cn>
Cc: linux-kernel@vger.kernel.org, OGAWA Hirofumi
 <hirofumi@mail.parknet.co.jp>, Yuan Tan <yuantan098@gmail.com>, Yifan Wu
 <yifanwucs@gmail.com>, Juefei Pu <tomapufckgml@gmail.com>, Xin Liu
 <bird@lzu.edu.cn>, Yemu Lu <prcups@krgm.moe>,
 linux-fsdevel@vger.kernel.org, Christian Brauner <brauner@kernel.org>
Subject: Re: [PATCH 1/1] fat: restore original value when fat_ent_write
 failed
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On Mon, 25 May 2026 16:56:49 +0800 Ren Wei <n05ec@lzu.edu.cn> wrote:

> From: Yemu Lu <prcups@krgm.moe>
> 
> fat_ent_write() may have committed the new link to the primary FAT
> but then failed on the mirror copy, leaving the chain pointing to
> new_dclus even though the caller will free it. Restore the original
> value to keep the chain consistent.

Thanks.

When fixing bugs, please be careful to describe the userspace-visible
effects of that bug.  Here I'm assuming "dereferences freed pointer,
kernel crashes"?

> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Cc: stable@kernel.org