From: Steven Rostedt <rostedt@goodmis.org>
To: Timur Tabi <timur@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
Matthew Wilcox <willy@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
Petr Mladek <pmladek@suse.com>,
roman.fietze@magna.com, keescook@chromium.org,
John Ogness <john.ogness@linutronix.de>,
linux-mm@kvack.org, Akinobu Mita <akinobu.mita@gmail.com>
Subject: Re: [PATCH 0/2] introduce DUMP_PREFIX_UNHASHED for hex dumps
Date: Tue, 26 Jan 2021 12:14:04 -0500 [thread overview]
Message-ID: <20210126121404.016117fd@gandalf.local.home> (raw)
In-Reply-To: <cd9e7a31-e4f6-69d3-0648-c6228108b592@kernel.org>
On Tue, 26 Jan 2021 10:59:12 -0600
Timur Tabi <timur@kernel.org> wrote:
> The only drawback to this idea is: what happens if distros start
> enabling CONFIG_PRINTK_NEVER_HASH by default, just because it makes
> debugging easier?
I do believe distros should be more concerned about security than using
this for making debugging easier.
Perhaps we should add the same banner print if that config is set as
trace_printk() has if it is detected in the kernel or a module:
**********************************************************
** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **
** **
** trace_printk() being used. Allocating extra memory. **
** **
** This means that this is a DEBUG kernel and it is **
** unsafe for production use. **
** **
** If you see this message and you are not debugging **
** the kernel, report this immediately to your vendor! **
** **
** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **
**********************************************************
But have:
**********************************************************
** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **
** **
** CONFIG_PRINTK_NEVER_HASH enabled **
** **
** This means that this is a DEBUG kernel and it is **
** unsafe for production use. **
** **
** If you see this message and you are not debugging **
** the kernel, report this immediately to your vendor! **
** **
** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **
**********************************************************
The above appears to keep people from using trace_printk(), I don't see why
it wouldn't work for this config ;-)
-- Steve
next prev parent reply other threads:[~2021-01-27 0:28 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-16 22:09 [PATCH 0/2] introduce DUMP_PREFIX_UNHASHED for hex dumps Timur Tabi
2021-01-16 22:09 ` [PATCH 1/2] [v2] lib/hexdump: introduce DUMP_PREFIX_UNHASHED for unhashed addresses Timur Tabi
2021-01-18 10:03 ` Andy Shevchenko
2021-01-18 15:57 ` Timur Tabi
2021-01-18 17:14 ` Andy Shevchenko
2021-01-18 17:53 ` Timur Tabi
2021-01-16 22:09 ` [PATCH 2/2] mm/page_poison: use unhashed address in hexdump for check_poison_mem() Timur Tabi
2021-01-18 18:26 ` [PATCH 0/2] introduce DUMP_PREFIX_UNHASHED for hex dumps Matthew Wilcox
2021-01-18 19:03 ` Timur Tabi
2021-01-19 0:53 ` Sergey Senozhatsky
2021-01-19 1:47 ` Matthew Wilcox
2021-01-19 10:38 ` Sergey Senozhatsky
2021-01-19 19:45 ` Kees Cook
2021-01-26 16:47 ` Vlastimil Babka
2021-01-26 16:59 ` Timur Tabi
2021-01-26 17:14 ` Steven Rostedt [this message]
2021-01-26 17:14 ` Vlastimil Babka
2021-01-26 17:30 ` Timur Tabi
2021-01-26 17:39 ` Steven Rostedt
2021-01-26 17:40 ` Steven Rostedt
2021-01-26 19:23 ` John Ogness
2021-01-27 2:11 ` Sergey Senozhatsky
2021-01-27 3:22 ` Timur Tabi
2021-01-27 10:11 ` Petr Mladek
2021-01-27 10:38 ` Vlastimil Babka
2021-01-19 19:45 ` Kees Cook
2021-01-19 19:55 ` Timur Tabi
2021-01-19 20:10 ` Steven Rostedt
2021-01-19 20:49 ` Timur Tabi
2021-01-19 21:15 ` Steven Rostedt
2021-01-19 21:25 ` Timur Tabi
2021-01-20 9:19 ` Petr Mladek
2021-01-20 12:17 ` Matthew Wilcox
2021-01-20 19:39 ` Linus Torvalds
2021-01-19 20:18 ` Randy Dunlap
2021-01-20 20:28 ` Kees Cook
2021-01-19 2:30 ` Timur Tabi
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