1 files changed, 16 insertions, 11 deletions

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 1525cd01dacd..408e1d0abfd1 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2088,14 +2088,22 @@ static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
 
 /**
  * nand_fill_oob - [Internal] Transfer client buffer to oob
- * @chip: nand chip structure
+ * @mtd: MTD device structure
  * @oob: oob data buffer
  * @len: oob data write length
  * @ops: oob ops structure
  */
-static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob, size_t len,
-                                                struct mtd_oob_ops *ops)
+static uint8_t *nand_fill_oob(struct mtd_info *mtd, uint8_t *oob, size_t len,
+                              struct mtd_oob_ops *ops)
 {
+        struct nand_chip *chip = mtd->priv;
+
+        /*
+         * Initialise to all 0xFF, to avoid the possibility of left over OOB
+         * data from a previous OOB read.
+         */
+        memset(chip->oob_poi, 0xff, mtd->oobsize);
+
         switch (ops->mode) {
 
         case MTD_OOB_PLACE:
@@ -2192,10 +2200,6 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
             (chip->pagebuf << chip->page_shift) < (to + ops->len))
                 chip->pagebuf = -1;
 
-        /* If we're not given explicit OOB data, let it be 0xFF */
-        if (likely(!oob))
-                memset(chip->oob_poi, 0xff, mtd->oobsize);
-
         /* Don't allow multipage oob writes with offset */
         if (oob && ops->ooboffs && (ops->ooboffs + ops->ooblen > oobmaxlen))
                 return -EINVAL;
@@ -2217,8 +2221,11 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
 
                 if (unlikely(oob)) {
                         size_t len = min(oobwritelen, oobmaxlen);
-                        oob = nand_fill_oob(chip, oob, len, ops);
+                        oob = nand_fill_oob(mtd, oob, len, ops);
                         oobwritelen -= len;
+                } else {
+                        /* We still need to erase leftover OOB data */
+                        memset(chip->oob_poi, 0xff, mtd->oobsize);
                 }
 
                 ret = chip->write_page(mtd, chip, wbuf, page, cached,
@@ -2392,10 +2399,8 @@ static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
         if (page == chip->pagebuf)
                 chip->pagebuf = -1;
 
-        memset(chip->oob_poi, 0xff, mtd->oobsize);
-        nand_fill_oob(chip, ops->oobbuf, ops->ooblen, ops);
+        nand_fill_oob(mtd, ops->oobbuf, ops->ooblen, ops);
         status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
-        memset(chip->oob_poi, 0xff, mtd->oobsize);
 
         if (status)
                 return status;