2024-05-14 10:55:52

by Sascha Hauer

Subject: [PATCH] mtd: rawnand: make rawnand_check_data_only_read_support() work

rawnand_check_data_only_read_support() calls nand_read_data_op() with a
NULL pointer as buffer which will immediately return an error. Allow a
NULL buffer pointer when check_only is requested. This should be safe to
do as nand_read_data_op() has no business in touching the buffer in
check_only mode.

Fixes: 9f820fc0651c ("mtd: rawnand: Check the data only read pattern only once")
Signed-off-by: Sascha Hauer <[email protected]>
---
drivers/mtd/nand/raw/nand_base.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index d7dbbd469b892..a5e7d8deafbbe 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -2173,7 +2173,7 @@ EXPORT_SYMBOL_GPL(nand_reset_op);
int nand_read_data_op(struct nand_chip *chip, void *buf, unsigned int len,
bool force_8bit, bool check_only)
{
- if (!len || !buf)
+ if (!len || (!buf && !check_only))
return -EINVAL;

if (nand_has_exec_op(chip)) {
--
2.39.2

2024-05-15 08:12:01

by Alexander Dahl

Subject: Re: [PATCH] mtd: rawnand: make rawnand_check_data_only_read_support() work

Hello Sascha,

Am Tue, May 14, 2024 at 12:33:55PM +0200 schrieb Sascha Hauer:
> rawnand_check_data_only_read_support() calls nand_read_data_op() with a
> NULL pointer as buffer which will immediately return an error. Allow a
> NULL buffer pointer when check_only is requested. This should be safe to
> do as nand_read_data_op() has no business in touching the buffer in
> check_only mode.
>
> Fixes: 9f820fc0651c ("mtd: rawnand: Check the data only read pattern only once")
> Signed-off-by: Sascha Hauer <[email protected]>
> ---
> drivers/mtd/nand/raw/nand_base.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
> index d7dbbd469b892..a5e7d8deafbbe 100644
> --- a/drivers/mtd/nand/raw/nand_base.c
> +++ b/drivers/mtd/nand/raw/nand_base.c
> @@ -2173,7 +2173,7 @@ EXPORT_SYMBOL_GPL(nand_reset_op);
> int nand_read_data_op(struct nand_chip *chip, void *buf, unsigned int len,
> bool force_8bit, bool check_only)
> {
> - if (!len || !buf)
> + if (!len || (!buf && !check_only))
> return -EINVAL;
>
> if (nand_has_exec_op(chip)) {

A very similar patch has been proposed by Miqu?l with
<[email protected]> recently. o.O

Greets
Alex

Link: https://lore.kernel.org/linux-mtd/[email protected]/