net: systemport: fix index check to avoid an array out of bounds access

net: systemport: fix index check to avoid an array out of bounds access

[ Upstream commit c0368595c1639947839c0db8294ee96aca0b3b86 ]

Currently the bounds check on index is off by one and can lead to
an out of bounds access on array priv->filters_loc when index is
RXCHK_BRCM_TAG_MAX.

Fixes: bb9051a2b230 ("net: systemport: Add support for WAKE_FILTER")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>