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From: Florian Weimer <fweimer@redhat.com>
To: Siddhesh Poyarekar <siddhesh@sourceware.org>
Cc: libc-alpha@sourceware.org,  dj@redhat.com,
	 Eyal Itkin <eyalit@checkpoint.com>
Subject: Re: [PATCH] Harden tcache double-free check
Date: Wed, 07 Jul 2021 19:17:19 +0200	[thread overview]
Message-ID: <87a6my2gdc.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <20210707012919.1298612-1-siddhesh@sourceware.org> (Siddhesh Poyarekar's message of "Wed, 7 Jul 2021 06:59:19 +0530")

* Siddhesh Poyarekar:

> +/* Process-wide key to try and catch a double-free in the same thread.  */
> +static uintptr_t tcache_key;
> +
> +/* The value of tcache_key does not really have to be a cryptographically
> +   secure random number.  It only needs to be arbitrary enough so that it does
> +   not collide with values present in applications, which would be quite rare,
> +   about 1 in 2^wordsize.  */

The comment should say that a collision could result in performance
problems.

Apart from that, the patch looks okay to me.

Thanks,
Florian


  reply	other threads:[~2021-07-07 17:17 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-07  1:29 Siddhesh Poyarekar
2021-07-07 17:17 ` Florian Weimer [this message]
2021-07-07 17:34   ` [PATCH v2] " Siddhesh Poyarekar
2021-07-07 17:35 ` [PATCH] " Adhemerval Zanella
2021-07-07 17:58   ` Siddhesh Poyarekar
2021-07-07 18:09     ` Adhemerval Zanella
2021-07-07 18:12       ` Siddhesh Poyarekar
2021-07-07 18:27         ` Adhemerval Zanella
2021-07-07 18:28           ` Siddhesh Poyarekar

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