Don't trust the TOC coming from the drive so much.

Be better about handling failures of SCSI CD READ TOC command.

diff --git a/sys/scsi/cd.c b/sys/scsi/cd.c
index 6867685..1ce727e 100644 (file)
--- a/sys/scsi/cd.c
+++ b/sys/scsi/cd.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: cd.c,v 1.51 1999/11/12 05:52:58 angelos Exp $ */
+/*     $OpenBSD: cd.c,v 1.52 2000/04/09 07:09:03 csapuntz Exp $        */
 /*     $NetBSD: cd.c,v 1.100 1997/04/02 02:29:30 mycroft Exp $ */
 
 /*
@@ -1173,6 +1173,7 @@ cdgetdisklabel(dev, cd, lp, clp, spoofonly)
        u_int8_t hdr[TOC_HEADER_SZ],  *ent, *toc = NULL;
        u_int32_t lba, nlba;
        int tocidx, i, n, len, is_data, data_track = -1;
+       int toc_valid = 0;
 
        bzero(lp, sizeof(struct disklabel));
        bzero(clp, sizeof(struct cpu_disklabel));
@@ -1221,9 +1222,15 @@ cdgetdisklabel(dev, cd, lp, clp, spoofonly)
         * disklabel read routine.  XXX should we move all data tracks up front
         * before any other tracks?
         */
+       bzero(hdr, sizeof(hdr));
        if (cd_read_toc(cd, 0, 0, hdr, TOC_HEADER_SZ, 0))
-               return;
+               goto done;
+
        n = hdr[TOC_HEADER_ENDING_TRACK] - hdr[TOC_HEADER_STARTING_TRACK] + 1;
+
+       if (n <= 0)
+               goto done;
+
        /* n + 1 because of leadout track */
        len = TOC_HEADER_SZ + (n + 1) * TOC_ENTRY_SZ;
        MALLOC(toc, u_int8_t *, len, M_TEMP, M_WAITOK);
@@ -1231,6 +1238,8 @@ cdgetdisklabel(dev, cd, lp, clp, spoofonly)
                goto done;
 
        /* Create the partition table.  */
+        /* Probably should sanity-check the drive's values */
+       toc_valid = 1;  
        ent = toc + TOC_HEADER_SZ;
        lba = ((cd->sc_link->quirks & ADEV_LITTLETOC) ?
            ent[TOC_ENTRY_MSF_LBA] | ent[TOC_ENTRY_MSF_LBA + 1] << 8 |
@@ -1240,9 +1249,7 @@ cdgetdisklabel(dev, cd, lp, clp, spoofonly)
            ent[TOC_ENTRY_MSF_LBA + 2] << 8 | ent[TOC_ENTRY_MSF_LBA + 3]);
 
        i = 0;
-       for (tocidx = hdr[TOC_HEADER_STARTING_TRACK]; 
-            tocidx <= hdr[TOC_HEADER_ENDING_TRACK]; 
-            tocidx++) {
+       for (tocidx = 1; tocidx <= n; tocidx++) {
                is_data = ent[TOC_ENTRY_CONTROL_ADDR_TYPE] & 4;
                ent += TOC_ENTRY_SZ;
                nlba = ((cd->sc_link->quirks & ADEV_LITTLETOC) ?
@@ -1284,15 +1291,9 @@ done:
                FREE(toc, M_TEMP);
 
        /* We have a data track, look in there for a real disklabel.  */
-       if (data_track != -1) {
-#if 0
-               /* This might not necessarily work */
-               errstring = readdisklabel(MAKECDDEV(major(dev), CDUNIT(dev), 
-                   data_track), cdstrategy, lp, clp, spoofonly);
-#else
+       if (data_track != -1 || !toc_valid) {
                errstring = readdisklabel(CDLABELDEV(dev),
                    cdstrategy, lp, clp, spoofonly);
-#endif
                /*if (errstring)
                        printf("%s: %s\n", cd->sc_dev.dv_xname, errstring);*/
        }
@@ -1508,6 +1509,7 @@ cd_read_toc(cd, mode, start, data, len, control)
        scsi_cmd.from_track = start;
        _lto2b(ntoc, scsi_cmd.data_len);
        scsi_cmd.control = control;
+
        return scsi_scsi_cmd(cd->sc_link, (struct scsi_generic *)&scsi_cmd,
            sizeof(struct scsi_read_toc), (u_char *)data, len, CDRETRIES,
            5000, NULL, SCSI_DATA_IN);