Tighten validation tests on an obscure corner case of

trying to align partitions to size <= 0 or past the
end of the disk. Emit error message in this case as
in other align errors.

Looks good to otto@.

diff --git a/sbin/disklabel/editor.c b/sbin/disklabel/editor.c
index 060d80d..b669a1d 100644 (file)
--- a/sbin/disklabel/editor.c
+++ b/sbin/disklabel/editor.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: editor.c,v 1.348 2018/08/30 13:07:19 krw Exp $        */
+/*     $OpenBSD: editor.c,v 1.349 2018/09/11 09:13:19 krw Exp $        */
 
 /*
  * Copyright (c) 1997-2000 Todd C. Miller <Todd.Miller@courtesan.com>
@@ -2505,25 +2505,34 @@ alignpartition(struct disklabel *lp, int partno, u_int64_t startalign,
                        break;
        }
        if (chunks[i].stop == 0) {
-               fprintf(stderr, "offset %llu is outside the OpenBSD bounds "
-                   "or inside another partition\n", start);
+               fprintf(stderr, "'%c' aligned offset %llu lies outside "
+                   "the OpenBSD bounds or inside another partition\n",
+                   'a' + partno, start);
                return (1);
        }
-       maxstop = (chunks[i].stop / stopalign) * stopalign;
 
        /* Calculate the new 'stop' sector, the sector after the partition. */
+       if ((flags & ROUND_SIZE_OVERLAP) == 0)
+               maxstop = (chunks[i].stop / stopalign) * stopalign;
+       else
+               maxstop = (ending_sector / stopalign) * stopalign;
+
        stop = DL_GETPOFFSET(pp) + DL_GETPSIZE(pp);
        if ((flags & ROUND_SIZE_UP) == ROUND_SIZE_UP)
                stop = ((stop + stopalign - 1) / stopalign) * stopalign;
        else if ((flags & ROUND_SIZE_DOWN) == ROUND_SIZE_DOWN)
                stop = (stop / stopalign) * stopalign;
-
-       if (((flags & ROUND_SIZE_OVERLAP) == 0) && stop  > maxstop)
+       if (stop > maxstop)
                stop = maxstop;
 
+       if (stop <= start) {
+               fprintf(stderr, "'%c' aligned size <= 0\n", 'a' + partno);
+               return (1);
+       }
+
        if (start != DL_GETPOFFSET(pp))
                DL_SETPOFFSET(pp, start);
-       if (stop > start && stop != DL_GETPOFFSET(pp) + DL_GETPSIZE(pp))
+       if (stop != DL_GETPOFFSET(pp) + DL_GETPSIZE(pp))
                DL_SETPSIZE(pp, stop - start);
 
        return (0);