[PATCH] libfc: update mfs boundry checking

[Robert Love <robert.w.love@intel.com>]

From: Vasu Dev <vasu.dev@intel.com>

A previous commit changed the mfs checking to ensure the new
mfs is less or equal to the mfs supported by the FCF. This
doesn't work for BRDCM cards as they set an mfs of 2048 regardless
of whether the switch returns a larger mfs.

This patch validates the new mfs against the upper and lower spec
defined boundries for a FCoE mfs.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
---
 drivers/scsi/libfc/fc_lport.c |   12 +++++++-----
 1 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/libfc/fc_lport.c b/drivers/scsi/libfc/fc_lport.c
index ef9560d..cc83b66 100644
--- a/drivers/scsi/libfc/fc_lport.c
+++ b/drivers/scsi/libfc/fc_lport.c
@@ -1742,17 +1742,19 @@ void fc_lport_flogi_resp(struct fc_seq *sp, struct fc_frame *fp,
 
 	mfs = ntohs(flp->fl_csp.sp_bb_data) &
 		FC_SP_BB_DATA_MASK;
-	if (mfs >= FC_SP_MIN_MAX_PAYLOAD &&
-	    mfs <= lport->mfs) {
-		lport->mfs = mfs;
-		fc_host_maxframe_size(lport->host) = mfs;
-	} else {
+
+	if (mfs < FC_SP_MIN_MAX_PAYLOAD || mfs > FC_SP_MAX_MAX_PAYLOAD) {
 		FC_LPORT_DBG(lport, "FLOGI bad mfs:%hu response, "
 			     "lport->mfs:%hu\n", mfs, lport->mfs);
 		fc_lport_error(lport, fp);
 		goto err;
 	}
 
+	if (mfs <= lport->mfs) {
+		lport->mfs = mfs;
+		fc_host_maxframe_size(lport->host) = mfs;
+	}
+
 	csp_flags = ntohs(flp->fl_csp.sp_features);
 	r_a_tov = ntohl(flp->fl_csp.sp_r_a_tov);
 	e_d_tov = ntohl(flp->fl_csp.sp_e_d_tov);