mtd: nand: add check for out of page read

[Linux-MTD Mailing List]

Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=e14feafbe0d5c6d64bb6fe4eba928cb57ac9a4c8
Commit:     e14feafbe0d5c6d64bb6fe4eba928cb57ac9a4c8
Parent:     1534b8b09757190ce6e97fa97f9ad77c49082cd8
Author:     Jason Liu <r64343 at freescale.com>
AuthorDate: Fri Nov 19 16:40:45 2010 +0800
Committer:  David Woodhouse <David.Woodhouse at intel.com>
CommitDate: Fri Dec 3 16:31:44 2010 +0000

    mtd: nand: add check for out of page read
    
    When run mtd_oobtest case, there will be one error for step(4),
    which turned out it need add one check for out of page read in
    nand_do_read_oob just like mtd_do_write_oob did it already.
    This commit also fix one typo error for comments in mtd_do_write_oob
    
    Signed-off-by: Jason Liu <r64343 at freescale.com>
    Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy at nokia.com>
    Signed-off-by: David Woodhouse <David.Woodhouse at intel.com>
---
 drivers/mtd/nand/nand_base.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 1f75a1b..75d199e 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1782,6 +1782,13 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
 	else
 		len = mtd->oobsize;
 
+	/* Do not allow read past end of page */
+	if ((ops->ooboffs + readlen) > len) {
+		DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt to read "
+				"past end of page\n", __func__);
+		return -EINVAL;
+	}
+
 	if (unlikely(ops->ooboffs >= len)) {
 		DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt to start read "
 					"outside oob\n", __func__);
@@ -2377,7 +2384,7 @@ static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
 		return -EINVAL;
 	}
 
-	/* Do not allow reads past end of device */
+	/* Do not allow write past end of device */
 	if (unlikely(to >= mtd->size ||
 		     ops->ooboffs + ops->ooblen >
 			((mtd->size >> chip->page_shift) -