[MTD] [NAND] Correctly validate out-of-band offset and length

Add checks to ensure that out-of-band reads and writes are
not attempted with an invalid offset or length.  Specifically,
the offset must be less than the size of oob for a page
and the length must not go beyond the size of the device.
Additionally the checks must adjust for auto-placement
(MTD_OOB_AUTO) of oob data.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
This commit is contained in:
Adrian Hunter 2007-01-31 17:58:29 +02:00 committed by David Woodhouse
parent cfa72397cf
commit 0373615579

View file

@ -1272,10 +1272,25 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
DEBUG(MTD_DEBUG_LEVEL3, "nand_read_oob: from = 0x%08Lx, len = %i\n",
(unsigned long long)from, readlen);
if (ops->mode == MTD_OOB_RAW)
len = mtd->oobsize;
else
if (ops->mode == MTD_OOB_AUTO)
len = chip->ecc.layout->oobavail;
else
len = mtd->oobsize;
if (unlikely(ops->ooboffs >= len)) {
DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
"Attempt to start read outside oob\n");
return -EINVAL;
}
/* Do not allow reads past end of device */
if (unlikely(from >= mtd->size ||
ops->ooboffs + readlen > ((mtd->size >> chip->page_shift) -
(from >> chip->page_shift)) * len)) {
DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
"Attempt read beyond end of device\n");
return -EINVAL;
}
chipnr = (int)(from >> chip->chip_shift);
chip->select_chip(mtd, chipnr);
@ -1742,19 +1757,40 @@ static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops)
{
int chipnr, page, status;
int chipnr, page, status, len;
struct nand_chip *chip = mtd->priv;
DEBUG(MTD_DEBUG_LEVEL3, "nand_write_oob: to = 0x%08x, len = %i\n",
(unsigned int)to, (int)ops->ooblen);
if (ops->mode == MTD_OOB_AUTO)
len = chip->ecc.layout->oobavail;
else
len = mtd->oobsize;
/* Do not allow write past end of page */
if ((ops->ooboffs + ops->ooblen) > mtd->oobsize) {
if ((ops->ooboffs + ops->ooblen) > len) {
DEBUG(MTD_DEBUG_LEVEL0, "nand_write_oob: "
"Attempt to write past end of page\n");
return -EINVAL;
}
if (unlikely(ops->ooboffs >= len)) {
DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
"Attempt to start write outside oob\n");
return -EINVAL;
}
/* Do not allow reads past end of device */
if (unlikely(to >= mtd->size ||
ops->ooboffs + ops->ooblen >
((mtd->size >> chip->page_shift) -
(to >> chip->page_shift)) * len)) {
DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
"Attempt write beyond end of device\n");
return -EINVAL;
}
chipnr = (int)(to >> chip->chip_shift);
chip->select_chip(mtd, chipnr);