2018-03-02 15:08:49

by Romain Izard

Subject: [PATCH RESEND] mtd: ubi: block: Fix error for write access

When opening a device with write access, ubiblock_open returns an error
code. Currently, this error code is -EPERM, but this is not the right
value.

The open function for other block devices returns -EROFS when opening
read-only devices with FMODE_WRITE set. When used with dm-verity, the
veritysetup userspace tool is expecting EROFS, and refuses to use the
ubiblock device.

Use -EROFS for ubiblock as well. As a result, veritysetup accepts the
ubiblock device as valid.

Fixes: 9d54c8a33eec (UBI: R/O block driver on top of UBI volumes)
Signed-off-by: Romain Izard <[email protected]>
---
drivers/mtd/ubi/block.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
index b210fdb31c98..4533423cf2aa 100644
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -242,7 +242,7 @@ static int ubiblock_open(struct block_device *bdev, fmode_t mode)
* in any case.
*/
if (mode & FMODE_WRITE) {
- ret = -EPERM;
+ ret = -EROFS;
goto out_unlock;
}

--
2.14.1

2018-03-02 15:21:08

by Richard Weinberger

Subject: Re: [PATCH RESEND] mtd: ubi: block: Fix error for write access

Am Freitag, 2. M?rz 2018, 12:16:18 CET schrieb Romain Izard:
> When opening a device with write access, ubiblock_open returns an error
> code. Currently, this error code is -EPERM, but this is not the right
> value.
>
> The open function for other block devices returns -EROFS when opening
> read-only devices with FMODE_WRITE set. When used with dm-verity, the
> veritysetup userspace tool is expecting EROFS, and refuses to use the
> ubiblock device.
>
> Use -EROFS for ubiblock as well. As a result, veritysetup accepts the
> ubiblock device as valid.
>
> Fixes: 9d54c8a33eec (UBI: R/O block driver on top of UBI volumes)
> Signed-off-by: Romain Izard <[email protected]>
> ---
> drivers/mtd/ubi/block.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
> index b210fdb31c98..4533423cf2aa 100644
> --- a/drivers/mtd/ubi/block.c
> +++ b/drivers/mtd/ubi/block.c
> @@ -242,7 +242,7 @@ static int ubiblock_open(struct block_device *bdev,
> fmode_t mode) * in any case.
> */
> if (mode & FMODE_WRITE) {
> - ret = -EPERM;
> + ret = -EROFS;

Queued for -next.

Thanks,
//richard