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Subject: Re: [PATCH] Documentation: Document the kernel flag
 bdev_allow_write_mounted
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: linux-doc@vger.kernel.org, corbet@lwn.net, jack@suse.cz,
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References: <20240819225626.2000752-2-gpiccoli@igalia.com>
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From: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
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On 22/08/2024 22:27, Darrick J. Wong wrote:
> [...]
>>
>> + Control the ability of directly writing to mounted block
>> + devices' page cache, i.e., allow / disallow writes that
>> + bypasses the FS. This was implemented as a means to
>> + prevent fuzzers to crash the kernel by breaking the
> 
>                 "...from crashing the kernel by overwriting
> the metadata underneath a mounted filesystem without its awareness."
> 
>> + filesystem without its awareness, through direct block
>> + device writes. Also prevents issues from direct writes
> 
> You can do it with buffered writes to the block device pagecache too.
> 
> "This also prevents destructive formatting of mounted filesystems by
> naïve storage tooling that don't use O_EXCL."
> 
> --D

Thanks! Just sent the V2.