[PATCH] md: Handle overflow of mdu_array_info_t->size better
mdu_array_info_t->size is 'int', which isn't big enough for the size (in KB of
each component in) some arrays.
So rather than a random overflow, set size to -1 when it cannot be set
correctly.
To update aspect on an array, userspace will sometimes:
get_array_info
change one field
set_array_info
in this case, we don't want the '-1' in 'size' to change to size, or look like
a size change at all. So test for that in update_array_info.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 653d4dcb..8f16174 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2942,6 +2942,8 @@
info.ctime = mddev->ctime;
info.level = mddev->level;
info.size = mddev->size;
+ if (info.size != mddev->size) /* overflow */
+ info.size = -1;
info.nr_disks = nr;
info.raid_disks = mddev->raid_disks;
info.md_minor = mddev->md_minor;
@@ -3523,7 +3525,7 @@
)
return -EINVAL;
/* Check there is only one change */
- if (mddev->size != info->size) cnt++;
+ if (info->size >= 0 && mddev->size != info->size) cnt++;
if (mddev->raid_disks != info->raid_disks) cnt++;
if (mddev->layout != info->layout) cnt++;
if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) cnt++;
@@ -3540,7 +3542,7 @@
else
return mddev->pers->reconfig(mddev, info->layout, -1);
}
- if (mddev->size != info->size)
+ if (info->size >= 0 && mddev->size != info->size)
rv = update_size(mddev, info->size);
if (mddev->raid_disks != info->raid_disks)