mtd: docg3 fix inbound calculations

The last erase block was not accessible, as the out of bound
check was incorrectly rejecting the last block.
The read/write/erase offset checks were forbidding the usage of the
last block, because of the calculation which was considering the
byte after the last instead of the last byte.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
index f5930ca..62e0111 100644 (file)
--- a/drivers/mtd/devices/docg3.c
+++ b/drivers/mtd/devices/docg3.c
@@ -872,11 +872,8 @@ static int doc_read_oob(struct mtd_info *mtd, loff_t from,
        if (ooblen % DOC_LAYOUT_OOB_SIZE)
                return -EINVAL;
 
-       ret = -EINVAL;
-       calc_block_sector(from + len, &block0, &block1, &page, &ofs,
-                         docg3->reliable);
-       if (block1 > docg3->max_block)
-               goto err;
+       if (from + len > mtd->size)
+               return -EINVAL;
 
        ops->oobretlen = 0;
        ops->retlen = 0;
@@ -1207,7 +1204,7 @@ static int doc_erase(struct mtd_info *mtd, struct erase_info *info)
        calc_block_sector(info->addr + info->len, &block0, &block1, &page,
                          &ofs, docg3->reliable);
        ret = -EINVAL;
-       if (block1 > docg3->max_block || page || ofs)
+       if (info->addr + info->len > mtd->size || page || ofs)
                goto reset_err;
 
        ret = 0;
@@ -1443,12 +1440,8 @@ static int doc_write_oob(struct mtd_info *mtd, loff_t ofs,
        if (len && ooblen &&
            (len / DOC_LAYOUT_PAGE_SIZE) != (ooblen / oobdelta))
                return -EINVAL;
-
-       ret = -EINVAL;
-       calc_block_sector(ofs + len, &block0, &block1, &page, &pofs,
-                         docg3->reliable);
-       if (block1 > docg3->max_block)
-               goto err;
+       if (ofs + len > mtd->size)
+               return -EINVAL;
 
        ops->oobretlen = 0;
        ops->retlen = 0;