[PATCH] staging: vhciq_core: replace snprintf with scnprintf

Dan Carpenter dan.carpenter at oracle.com
Wed Sep 11 14:46:12 UTC 2019

On Wed, Sep 11, 2019 at 07:55:43PM +0530, Rohit Sarkar wrote:
> On Wed, Sep 11, 2019 at 04:17:25PM +0200, Stefan Wahren wrote:
> > Hi Rohit,
> > 
> > On 11.09.19 15:51, Rohit Sarkar wrote:
> > > When the number of bytes to be printed exceeds the limit snprintf
> > > returns the number of bytes that would have been printed (if there was
> > > no truncation). This might cause issues, hence use scnprintf which
> > > returns the actual number of bytes printed to buffer always
> > >
> > > Signed-off-by: Rohit Sarkar <rohitsarkar5398 at gmail.com>
> > thanks for your patch. Did you test your change on the Raspberry Pi?
> Hey Stefan,
> No I haven't done so as I thought this is a generic change?
> Will that be necessary?

No.  It's not required.  The patch is easy to audit and clearly

The question would be does it actually fix a bug?  I looked at it and
some of the strings are definitely a bit long.  The longest one I saw
	"  Slots: %d available (%d data), %d recyclable, %d stalls (%d data)",
	123456789 123456789 123456789 123456789 123456789 123456789 123456789

If you get a lot of stalls, then that looks like it could lead to a
read overflow (an information leak).  Either way this does make the
code a bit easier to audit so it seems like a nice cleanup.  Next time
though, I really would prefer if you put this sort analysis in your
commit message so I can just glance over it.  (I'm lazy).

Reviewed-by: Dan Carpenter <dan.carpenter at oracle.com>

dan carpenter

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