libfdisk: don't offer zero length freespace

Reported-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libfdisk/src/table.c b/libfdisk/src/table.c
index 9be57139e2ed7e0b33e5cc360a986ec232577cc5..6d8cbc25aba7f200b6f90dd168865c3513f0890b 100644 (file)
--- a/libfdisk/src/table.c
+++ b/libfdisk/src/table.c
@@ -394,6 +394,8 @@ static int new_freespace(struct fdisk_context *cxt,
                         struct fdisk_partition *parent,
                         struct fdisk_partition **pa)
 {
+       fdisk_sector_t aligned_start, size;
+
        assert(cxt);
        assert(pa);
 
@@ -401,17 +403,26 @@ static int new_freespace(struct fdisk_context *cxt,
 
        if (start == end)
                return 0;
-       *pa = fdisk_new_partition();
-       if (!*pa)
-               return -ENOMEM;
 
        assert(start);
        assert(end);
        assert(end > start);
 
+       aligned_start = fdisk_align_lba_in_range(cxt, start, start, end);
+       size = end - aligned_start + 1ULL;
+
+       if (size == 0) {
+               DBG(TAB, ul_debug("ignore freespace (aligned size is zero)"));
+               return 0;
+       }
+
+       *pa = fdisk_new_partition();
+       if (!*pa)
+               return -ENOMEM;
+
        (*pa)->freespace = 1;
-       (*pa)->start = fdisk_align_lba_in_range(cxt, start, start, end);
-       (*pa)->size = end - (*pa)->start + 1ULL;
+       (*pa)->start = aligned_start;
+       (*pa)->size = size;
 
        if (parent)
                (*pa)->parent_partno = parent->partno;