DDF: add_to_super_ddf: be careful with workspace_lba

Some vendor DDF structures interpret workspace_lba
very differently then us. Make a sanity check on the value
before using it for config_size.

Signed-off-by: Martin Wilck <mwilck@arcor.de>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/super-ddf.c b/super-ddf.c
index 002b2717fc581f2b3c7f305ffe7bbcd5cdc68d05..400088eb3a1fadc7707fd27e1f739b2a99f28fd2 100644 (file)
--- a/super-ddf.c
+++ b/super-ddf.c
@@ -2703,6 +2703,31 @@ static unsigned int find_unused_pde(const struct ddf_super *ddf)
        return DDF_NOTFOUND;
 }
 
+static void _set_config_size(struct phys_disk_entry *pde, const struct dl *dl)
+{
+       __u64 cfs, t;
+       cfs = min(dl->size - 32*1024*2ULL, be64_to_cpu(dl->primary_lba));
+       t = be64_to_cpu(dl->secondary_lba);
+       if (t != ~(__u64)0)
+               cfs = min(cfs, t);
+       /*
+        * Some vendor DDF structures interpret workspace_lba
+        * very differently then us. Make a sanity check on the value.
+        */
+       t = be64_to_cpu(dl->workspace_lba);
+       if (t < cfs) {
+               __u64 wsp = cfs - t;
+               if (wsp > 1024*1024*2ULL && wsp > dl->size / 16) {
+                       pr_err("%s: %x:%x: workspace size 0x%llx too big, ignoring\n",
+                              __func__, dl->major, dl->minor, wsp);
+               } else
+                       cfs = t;
+       }
+       pde->config_size = cpu_to_be64(cfs);
+       dprintf("%s: %x:%x config_size %llx, DDF structure is %llx blocks\n",
+               __func__, dl->major, dl->minor, cfs, dl->size-cfs);
+}
+
 /* add a device to a container, either while creating it or while
  * expanding a pre-existing container
  */
@@ -2825,7 +2850,7 @@ static int add_to_super_ddf(struct supertype *st,
        if (ddf->dlist == NULL ||
            be64_to_cpu(ddf->dlist->secondary_lba) != ~(__u64)0)
                __calc_lba(dd, ddf->dlist, secondary_lba, 32);
-       pde->config_size = dd->workspace_lba;
+       _set_config_size(pde, dd);
 
        sprintf(pde->path, "%17.17s","Information: nil") ;
        memset(pde->pad, 0xff, 6);