mtd: nand: cleanup the nand_do_write_ops

nand_do_write_ops was broken in regard to writing several pages, each 
with its own oob.

Although nand_do_write_ops intends to allow such mode, it fails do do so
Probably this was never tested.

Also add missing checks for attempts to write at illegal offsets.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 17 insertions, 7 deletions

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index cada4cffacf8..138674183c1c 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2072,11 +2072,9 @@ static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
  * @oob:        oob data buffer
  * @ops:        oob ops structure
  */
-static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob,
-                                  struct mtd_oob_ops *ops)
+static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob, size_t len,
+                                                struct mtd_oob_ops *ops)
 {
-        size_t len = ops->ooblen;
-
         switch(ops->mode) {
 
         case MTD_OOB_PLACE:
@@ -2131,6 +2129,11 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
         int chipnr, realpage, page, blockmask, column;
         struct nand_chip *chip = mtd->priv;
         uint32_t writelen = ops->len;
+
+        uint32_t oobwritelen = ops->ooblen;
+        uint32_t oobmaxlen = ops->mode == MTD_OOB_AUTO ?
+                                mtd->oobavail : mtd->oobsize;
+
         uint8_t *oob = ops->oobbuf;
         uint8_t *buf = ops->datbuf;
         int ret, subpage;
@@ -2172,6 +2175,10 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
         if (likely(!oob))
                 memset(chip->oob_poi, 0xff, mtd->oobsize);
 
+        /* Don't allow multipage oob writes with offset */
+        if (ops->ooboffs && (ops->ooboffs + ops->ooblen > oobmaxlen))
+                return -EINVAL;
+
         while(1) {
                 int bytes = mtd->writesize;
                 int cached = writelen > bytes && page != blockmask;
@@ -2187,8 +2194,11 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
                         wbuf = chip->buffers->databuf;
                 }
 
-                if (unlikely(oob))
-                        oob = nand_fill_oob(chip, oob, ops);
+                if (unlikely(oob)) {
+                        size_t len = min(oobwritelen, oobmaxlen);
+                        oob = nand_fill_oob(chip, oob, len, ops);
+                        oobwritelen -= len;
+                }
 
                 ret = chip->write_page(mtd, chip, wbuf, page, cached,
                                        (ops->mode == MTD_OOB_RAW));
@@ -2362,7 +2372,7 @@ static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
                 chip->pagebuf = -1;
 
         memset(chip->oob_poi, 0xff, mtd->oobsize);
-        nand_fill_oob(chip, ops->oobbuf, ops);
+        nand_fill_oob(chip, ops->oobbuf, ops->ooblen, ops);
         status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
         memset(chip->oob_poi, 0xff, mtd->oobsize);