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From: "Valdis Klētnieks" <valdis.kletnieks@vt.edu>
To: Richard Sailer <richard_siegfried@systemli.org>
Cc: kernelnewbies <Kernelnewbies@kernelnewbies.org>
Subject: Re: Dubios pointer casting with put_user()
Date: Fri, 17 Jul 2020 18:46:46 -0400
Message-ID: <96764.1595026006@turing-police> (raw)
In-Reply-To: <d8a96eaf-3cbf-a088-5dd5-ad8b64ec9749@systemli.org>

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On Fri, 17 Jul 2020 02:13:34 +0200, Richard Sailer said:

> unsigned long. Is this (correctness and security wise) sane? Because as
> I understand it put_user() determines the amount it copies from the
> pointer type.

> 		rc = put_user(amount, (int __user *)arg);

If that were true, you wouldn't need to pass the 'amount' variable....

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Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-17  0:13 Richard Sailer
2020-07-17  0:19 ` Richard Sailer
2020-07-17 22:46 ` Valdis Klētnieks [this message]
2020-07-19 12:15   ` Richard Sailer
2020-07-19 22:50     ` Valdis Klētnieks

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