commit
093019cf1b18dd31b2c3b77acce4e000e2cbc9ce upstream.
Commit
fa8b18ed didn't prevent the integer overflow and possible
memory corruption. "count" can go negative and bypass the check.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>