[SCSI] libfc: fix symbolic name registrations smashing skb data

The strncpy for RSPN_ID and RSNN_NN requests was padding
past the allocated frame size.

Get the string length before filling in the ct header.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 9 insertions, 8 deletions

diff --git a/include/scsi/fc_encode.h b/include/scsi/fc_encode.h
index c8968d31c610..ab2260cb149c 100644
--- a/include/scsi/fc_encode.h
+++ b/include/scsi/fc_encode.h
@@ -111,6 +111,7 @@ static inline int fc_ct_fill(struct fc_lport *lport,
                       enum fc_fh_type *fh_type)
 {
         struct fc_ct_req *ct;
+        size_t len;
 
         switch (op) {
         case FC_NS_GPN_FT:
@@ -138,22 +139,22 @@ static inline int fc_ct_fill(struct fc_lport *lport,
                 break;
 
         case FC_NS_RSPN_ID:
-                ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rspn));
+                len = strnlen(fc_host_symbolic_name(lport->host), 255);
+                ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rspn) + len);
                 hton24(ct->payload.spn.fr_fid.fp_fid,
                        fc_host_port_id(lport->host));
                 strncpy(ct->payload.spn.fr_name,
-                        fc_host_symbolic_name(lport->host), 255);
-                ct->payload.spn.fr_name_len =
-                        strnlen(ct->payload.spn.fr_name, 255);
+                        fc_host_symbolic_name(lport->host), len);
+                ct->payload.spn.fr_name_len = len;
                 break;
 
         case FC_NS_RSNN_NN:
-                ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rsnn));
+                len = strnlen(fc_host_symbolic_name(lport->host), 255);
+                ct = fc_ct_hdr_fill(fp, op, sizeof(struct fc_ns_rsnn) + len);
                 put_unaligned_be64(lport->wwnn, &ct->payload.snn.fr_wwn);
                 strncpy(ct->payload.snn.fr_name,
-                        fc_host_symbolic_name(lport->host), 255);
-                ct->payload.snn.fr_name_len =
-                        strnlen(ct->payload.snn.fr_name, 255);
+                        fc_host_symbolic_name(lport->host), len);
+                ct->payload.snn.fr_name_len = len;
                 break;
 
         default: