gigaset: gigaset_isowbuf_getbytes() may return signed unnoticed

ifd->offset is unsigned.  gigaset_isowbuf_getbytes() may return signed
unnoticed.  Revised version of patch originally submitted by Roel Kluin
<12o3l@tiscali.nl>.

Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/isdn/gigaset/bas-gigaset.c b/drivers/isdn/gigaset/bas-gigaset.c
index 5255b5e..3f11910 100644 (file)
--- a/drivers/isdn/gigaset/bas-gigaset.c
+++ b/drivers/isdn/gigaset/bas-gigaset.c
@@ -1050,10 +1050,9 @@ static int submit_iso_write_urb(struct isow_urbctx_t *ucx)
                }
 
                /* retrieve block of data to send */
-               ifd->offset = gigaset_isowbuf_getbytes(ubc->isooutbuf,
-                                                      ifd->length);
-               if (ifd->offset < 0) {
-                       if (ifd->offset == -EBUSY) {
+               rc = gigaset_isowbuf_getbytes(ubc->isooutbuf, ifd->length);
+               if (rc < 0) {
+                       if (rc == -EBUSY) {
                                gig_dbg(DEBUG_ISO,
                                        "%s: buffer busy at frame %d",
                                        __func__, nframe);
@@ -1062,11 +1061,12 @@ static int submit_iso_write_urb(struct isow_urbctx_t *ucx)
                        } else {
                                dev_err(ucx->bcs->cs->dev,
                                        "%s: buffer error %d at frame %d\n",
-                                       __func__, ifd->offset, nframe);
-                               return ifd->offset;
+                                       __func__, rc, nframe);
+                               return rc;
                        }
                        break;
                }
+               ifd->offset = rc;
                ucx->limit = ubc->isooutbuf->nextread;
                ifd->status = 0;
                ifd->actual_length = 0;