Re: [PATCH v2 2/2] soc: qcom: rmtfs-mem: Make sysfs attributes world-readable

From: Bjorn Andersson
Date: Fri Dec 21 2018 - 17:06:46 EST


On Fri 21 Dec 12:10 PST 2018, Evan Green wrote:

> In order to run an rmtfs daemon as an unprivileged user, that user would
> need access to the phys_addr and size sysfs attributes. Sharing these
> attributes with unprivileged users doesn't really leak anything
> sensitive, since if you have access to physical memory, the jig is
> up anyway.
>
> Make those attributes readable by all.
>
> Signed-off-by: Evan Green <evgreen@xxxxxxxxxxxx>
> Reviewed-by: Brian Norris <briannorris@xxxxxxxxxxxx>

Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

Regards,
Bjorn

> ---
>
> Changes in v2: None
>
> drivers/soc/qcom/rmtfs_mem.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/soc/qcom/rmtfs_mem.c b/drivers/soc/qcom/rmtfs_mem.c
> index 99a1363ece254..815c11aeceb93 100644
> --- a/drivers/soc/qcom/rmtfs_mem.c
> +++ b/drivers/soc/qcom/rmtfs_mem.c
> @@ -45,9 +45,9 @@ static ssize_t qcom_rmtfs_mem_show(struct device *dev,
> struct device_attribute *attr,
> char *buf);
>
> -static DEVICE_ATTR(phys_addr, 0400, qcom_rmtfs_mem_show, NULL);
> -static DEVICE_ATTR(size, 0400, qcom_rmtfs_mem_show, NULL);
> -static DEVICE_ATTR(client_id, 0400, qcom_rmtfs_mem_show, NULL);
> +static DEVICE_ATTR(phys_addr, 0444, qcom_rmtfs_mem_show, NULL);
> +static DEVICE_ATTR(size, 0444, qcom_rmtfs_mem_show, NULL);
> +static DEVICE_ATTR(client_id, 0444, qcom_rmtfs_mem_show, NULL);
>
> static ssize_t qcom_rmtfs_mem_show(struct device *dev,
> struct device_attribute *attr,
> --
> 2.18.1
>