Illumos #1661: Fix flaw in sa_find_sizes() calculation

When calculating space needed for SA_BONUS buffers, hdrsize is
always rounded up to next 8-aligned boundary. However, in two places
the round up was done against sum of 'total' plus hdrsize. On the
other hand, hdrsize increments by 4 each time, which means in certain
conditions, we would end up returning with will_spill == 0 and
(total + hdrsize) larger than full_space, leading to a failed
assertion because it's invalid for dmu_set_bonus.

Reviewed by: Matthew Ahrens <matt@delphix.com>
Reviewed by: Dan McDonald <danmcd@nexenta.com>
Approved by: Gordon Ross <gwr@nexenta.com>

References to Illumos issue:
  https://www.illumos.org/issues/1661

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #426
This commit is contained in:
Xin Li 2011-10-21 16:39:53 -07:00 committed by Brian Behlendorf
parent 3cee2262a6
commit c475167627

View File

@ -607,14 +607,14 @@ sa_find_sizes(sa_os_t *sa, sa_bulk_attr_t *attr_desc, int attr_count,
* and spill buffer.
*/
if (buftype == SA_BONUS && *index == -1 &&
P2ROUNDUP(*total + hdrsize, 8) >
(*total + P2ROUNDUP(hdrsize, 8)) >
(full_space - sizeof (blkptr_t))) {
*index = i;
done = B_TRUE;
}
next:
if (P2ROUNDUP(*total + hdrsize, 8) > full_space &&
if ((*total + P2ROUNDUP(hdrsize, 8)) > full_space &&
buftype == SA_BONUS)
*will_spill = B_TRUE;
}