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From:   Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Date:   Tue, 25 Sep 2018 21:16:04 +0900
To:     He Zhe <zhe.he@windriver.com>
Cc:     Petr Mladek <pmladek@suse.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        sergey.senozhatsky@gmail.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] printk: Fix panic caused by passing log_buf_len
 to command line
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On (09/22/18 23:36), He Zhe wrote:
> I'd like to fix the above issues. But can I have your opinions about how to
> handle the syscall?

Hmm. This part is complex, I need to look at it more.
A signed int is a good buffer size limit for 32-bit user space.
But this also means that syslog might experience some problems
doing SYSLOG_ACTION_READ_ALL on a 32-bit system with a 4G log_buf.
Not to mention SYSLOG_ACTION_READ_ALL on a 64-bit system with a
log_buf=32G. So *maybe* things are alredy a bit broken in this
department. Dunno, need to think more.

	-ss