From: John Ogness <john.ogness@linutronix.de>
To: Sven Schnelle <svens@linux.ibm.com>
Cc: Petr Mladek <pmladek@suse.com>,
Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] printk: fix buffer overflow potential for print_text()
Date: Sun, 24 Jan 2021 09:19:40 +0106 [thread overview]
Message-ID: <87k0s2n45n.fsf@jogness.linutronix.de> (raw)
In-Reply-To: <yt9d8s8je3gc.fsf@linux.ibm.com>
Hi Sven,
Thanks for the outstanding analysis!
On 2021-01-23, Sven Schnelle <svens@linux.ibm.com> wrote:
>> 1401 if (buf_size > 0)
>> 1402 text[len] = 0;
>
> I don't think i have really understood how all the printk magic works,
> but using r->text_buf[len] seems to be the correct place to put the
> zero byte in that case?
Yes, you are correct! @text is pointing to the beginning of the
currently processed line, not the beginning of the buffer.
I will submit a patch to fix our recent fix (unless you would like to do
that).
Thank you for all your help with this!
John Ogness
next prev parent reply other threads:[~2021-01-24 8:14 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-14 17:04 [PATCH] printk: fix buffer overflow potential for print_text() John Ogness
2021-01-15 12:04 ` Petr Mladek
2021-01-15 12:07 ` Petr Mladek
2021-01-19 0:44 ` Sergey Senozhatsky
2021-01-19 8:54 ` John Ogness
2021-01-19 10:29 ` Sergey Senozhatsky
2021-01-19 11:44 ` John Ogness
2021-01-19 12:22 ` Petr Mladek
2021-01-19 11:20 ` Petr Mladek
2021-01-15 14:16 ` John Ogness
2021-01-15 16:04 ` Petr Mladek
2021-01-22 21:21 ` Sven Schnelle
2021-01-22 23:42 ` John Ogness
2021-01-23 21:18 ` Sven Schnelle
2021-01-23 21:41 ` Sven Schnelle
2021-01-24 8:13 ` John Ogness [this message]
2021-01-24 8:59 ` Sven Schnelle
2021-02-26 17:19 ` Alexander Gordeev
2021-02-26 17:39 ` John Ogness
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