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From: Greg KH <gregkh@linuxfoundation.org>
To: Sasha Levin <levinsasha928@gmail.com>
Cc: arnd@arndb.de, viro@zeniv.linux.org.uk, davej@redhat.com,
	tglx@linutronix.de, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] kmsg: Use vmalloc instead of kmalloc when writing
Date: Fri, 30 Mar 2012 08:30:13 -0700	[thread overview]
Message-ID: <20120330153013.GC18488@kroah.com> (raw)
In-Reply-To: <1333127067-2043-1-git-send-email-levinsasha928@gmail.com>

On Fri, Mar 30, 2012 at 01:04:27PM -0400, Sasha Levin wrote:
> There are no size checks in kmsg_write(), and we try allocating enough
> memory to store everything userspace gave us, which may be too much for
> kmalloc to allocate.

Really?  Have you seen this fail?  As only root can do this, is this
really a problem?

> One option would be to limit it to something, but we can't come up with
> a number that would make sense.
> 
> Instead, just use vmalloc so that nothing would break with large amounts
> of data.

Are you sure this will work properly?  Have you tested it with large
amounts of data?

thanks,

greg k-h

  reply	other threads:[~2012-03-30 15:30 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-03-30 17:04 [PATCH] kmsg: Use vmalloc instead of kmalloc when writing Sasha Levin
2012-03-30 15:30 ` Greg KH [this message]
2012-03-30 16:37   ` Sasha Levin
2012-03-30 16:49     ` Greg KH
2012-03-30 17:15       ` Sasha Levin
2012-03-30 20:35       ` Thomas Gleixner
2012-03-30 20:42         ` Greg KH
2012-03-30 20:49           ` Thomas Gleixner
2012-03-30 21:05             ` Arnd Bergmann
2012-03-30 21:17               ` Greg KH
2012-03-30 22:02                 ` Sasha Levin
2012-03-30 23:43                   ` Greg KH
2012-03-31  0:02                     ` Kay Sievers
2012-03-31  8:57                       ` Sasha Levin
2012-04-23  9:54                     ` Sasha Levin
2012-03-30 21:18               ` Thomas Gleixner
2012-03-31  1:43               ` Joe Perches

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