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	Fri, 02 May 2025 17:13:16 +0000
Date: Fri, 2 May 2025 18:13:16 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Andrey Kriulin <kitotavrik.s@gmail.com>
Cc: Christian Brauner <brauner@kernel.org>,
	Andrey Kriulin <kitotavrik.media@gmail.com>,
	"Matthew Wilcox (Oracle)" <willy@infradead.org>,
	Josef Bacik <josef@toxicpanda.com>, NeilBrown <neilb@suse.de>,
	Jan Kara <jack@suse.cz>, linux-kernel@vger.kernel.org,
	lvc-project@linuxtesting.org, stable@vger.kernel.org
Subject: Re: [PATCH] fs: minix: Fix handling of corrupted directories
Message-ID: <20250502171316.GY2023217@ZenIV>
References: <20250502165059.63012-1-kitotavrik.media@gmail.com>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Fri, May 02, 2025 at 07:50:57PM +0300, Andrey Kriulin wrote:
> If the directory is corrupted and the number of nlinks is less than 2 
> (valid nlinks have at least 2), then when the directory is deleted, the
> minix_rmdir will try to reduce the nlinks(unsigned int) to a negative
> value.
> 
> Make nlinks validity check for directory in minix_lookup.
 
Not sure it's a good mitigation strategy - if nothing else, doing that
on r/o filesystem is clear loss...