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From: David Laight <david.laight.linux@gmail.com>
To: Dan Carpenter <error27@gmail.com>
Cc: Mohammad Davoudi <mdavoudi2011@gmail.com>,
	johan@kernel.org, elder@kernel.org, gregkh@linuxfoundation.org,
	rmfrfs@gmail.com, greybus-dev@lists.linaro.org,
	linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] staging: greybus: Replace sprintf with sysfs_emit
Date: Thu, 16 Jul 2026 10:47:32 +0100	[thread overview]
Message-ID: <20260716104732.7123b1cd@pumpkin> (raw)
In-Reply-To: <alf8N5msXi95aQfB@stanley.mountain>

On Thu, 16 Jul 2026 00:31:35 +0300
Dan Carpenter <error27@gmail.com> wrote:

> On Wed, Jul 15, 2026 at 05:28:58PM +0000, Mohammad Davoudi wrote:
> > Replace sprintf() with sysfs_emit() in sysfs show functions.
> > The sprintf() function is unaware of the PAGE_SIZE limit of the sysfs
> > buffer, which can potentially lead to buffer overruns. sysfs_emit()
> > is strictly designed for sysfs attributes and inherently protects
> > against buffer boundaries.
> > 
> > Signed-off-by: Mohammad Davoudi <MDavoudi2011@gmail.com>  
> 
> We're not applying this kind of patch in cases where sprintf is fine.
> 
> Really, I never like commit messages which talk about "potential
> buffer overruns".  Is it a buffer overrun or not?  If it's really
> hard to figure out then say that "This code is really hard to figure
> out and I suspect its fine but let's be safe."
> 
> In this case the code is really simple and we can all see the original
> code is fine just from reading the diff...

And you also have to double-check that it is valid to call sysfs_emit()
in that context.
The call sequences aren't all that obvious and are difficult to verify.

	David

> 
> regards,
> dan carpenter
> 
> 


      reply	other threads:[~2026-07-16  9:47 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-15 17:28 [PATCH] staging: greybus: Replace sprintf with sysfs_emit Mohammad Davoudi
2026-07-15 21:31 ` Dan Carpenter
2026-07-16  9:47   ` David Laight [this message]

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