Drivers are supposed to set correct ecc->{size,strength,bytes} before
calling nand_scan_tail(), but it does not complain about ecc->total
bigger than oobsize.
In this case, chip->scan_bbt() crashes due to memory corruption, but
it is hard to debug. It would be kind to fail it earlier with a clear
message.
Signed-off-by: Masahiro Yamada <yamada.masah...@socionext.com>
---
I was actually hit by this case.
I wasted half a day until I figured out my coding mistake in my
Denali driver. It will be helpful to check this in NAND core.
drivers/mtd/nand/nand_base.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index f4d686192717..14d6a5aa3ee8 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -4970,6 +4970,11 @@ int nand_scan_tail(struct mtd_info *mtd)
goto err_free;
}
ecc->total = ecc->steps * ecc->bytes;
+ if (ecc->total > mtd->oobsize) {
+ WARN(1, "Total number of ECC bytes exceeded oobsize\n");
+ ret = -EINVAL;
+ goto err_free;
+ }
/*
* The number of bytes available for a client to place data into
--
2.7.4
