On Mon, Sep 26, 2016 at 11:37 AM, Christoph Hellwig [off-list ref] wrote:

quoted

+     zones = kzalloc(sizeof(struct blk_zone) * rep.nr_zones,
+                     GFP_KERNEL);
+     if (!zones)
+             return -ENOMEM;

This should use kcalloc to get us underflow checking for the user
controlled allocation size.

Ah. yes. Will fix that.

quoted

+     if (copy_to_user(argp, &rep, sizeof(struct blk_zone_report))) {
+             ret = -EFAULT;
+             goto out;
+     }
+
+     if (rep.nr_zones) {
+             if (copy_to_user(argp + sizeof(struct blk_zone_report), zones,
+                              sizeof(struct blk_zone) * rep.nr_zones))
+                     ret = -EFAULT;
+     }

We could actually do this with a single big copy_to_user.  Not that
it really matters, though..

Except our source locations are disjoint (stack and kcalloc'd).

quoted

-/*
- * Zone type.
- */
-enum blk_zone_type {
-     BLK_ZONE_TYPE_UNKNOWN,
-     BLK_ZONE_TYPE_CONVENTIONAL,
-     BLK_ZONE_TYPE_SEQWRITE_REQ,
-     BLK_ZONE_TYPE_SEQWRITE_PREF,
-};

Please don't move this code around after it was added just two
patches earlier.  I'd say just split adding the new blkzoned.h
uapi header into a patch of it's own and add that before the
core block code.

Sounds good. Will reshuffle the patchset tonight.

Thanks!
-- 
Shaun Tancheff