avoid potential stack overflow by correctly checking count parameter
Reported-by: NIlja <ilja@netric.org>
Signed-off-by: NHelge Deller <deller@gmx.de>
Acked-by: NKyle McMartin <kyle@mcmartin.ca>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>