From: "Martin K. Petersen" <martin.petersen@oracle.com>
To: Christoph Hellwig <hch@lst.de>
Cc: axboe@kernel.dk, martin.petersen@oracle.com, linux-block@vger.kernel.org
Subject: Re: [PATCH] block: initialize integrity buffer to zero before writing it to media
Date: Thu, 06 Jun 2024 10:08:20 -0400 [thread overview]
Message-ID: <yq1msny6ucc.fsf@ca-mkp.ca.oracle.com> (raw)
In-Reply-To: <20240606052754.3462514-1-hch@lst.de> (Christoph Hellwig's message of "Thu, 6 Jun 2024 07:27:45 +0200")
Christoph,
> Metadata added by bio_integrity_prep is using plain kmalloc, which
> leads to random kernel memory being written media. For PI metadata
> this is limited to the app tag that isn't used by kernel generated
> metadata, but for non-PI metadata the entire buffer leaks kernel
> memory.
We do explicitly set the app_tag to 0 for PI so it's only non-PI
metadata that's affected.
> Fix this by adding the __GFP_ZERO flag to allocations for writes.
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
--
Martin K. Petersen Oracle Linux Engineering
next prev parent reply other threads:[~2024-06-06 14:08 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-06-06 5:27 [PATCH] block: initialize integrity buffer to zero before writing it to media Christoph Hellwig
2024-06-06 14:08 ` Martin K. Petersen [this message]
2024-06-06 14:10 ` Christoph Hellwig
2024-06-07 5:40 ` Christoph Hellwig
2024-06-10 10:39 ` Kanchan Joshi
2024-06-10 2:51 ` Chaitanya Kulkarni
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