Re: [PATCH v2 4/4] nvme: Allow reauth from sysfs

[Hannes Reinecke]

On 11/12/25 00:45, alistair23@xxxxxxxxx wrote:
> From: Alistair Francis <alistair.francis@xxxxxxx>
>
> Allow userspace to trigger a reauth (REPLACETLSPSK) from sysfs.
> This can be done by writing to the sysfs file.
>
> echo 0 > /sys/devices/virtual/nvme-fabrics/ctl/nvme0/tls_configured_key
>
> Signed-off-by: Alistair Francis <alistair.francis@xxxxxxx>
> ---
> v2:
>   - Trigger on any value written to `tls_configured_key`
>
>   drivers/nvme/host/sysfs.c | 23 ++++++++++++++++++++++-
>   1 file changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/nvme/host/sysfs.c b/drivers/nvme/host/sysfs.c
> index 6d10e12136d0..db1c53e00501 100644
> --- a/drivers/nvme/host/sysfs.c
> +++ b/drivers/nvme/host/sysfs.c
> @@ -806,7 +806,28 @@ static ssize_t tls_configured_key_show(struct device *dev,
>   
>   	return sysfs_emit(buf, "%08x\n", key_serial(key));
>   }
> -static DEVICE_ATTR_RO(tls_configured_key);
> +
> +static ssize_t tls_configured_key_store(struct device *dev,
> +					struct device_attribute *attr,
> +					const char *buf, size_t count)
> +{
> +	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
> +	int error;
> +
> +	if (!ctrl->opts || !ctrl->opts->concat)
> +		return -EOPNOTSUPP;
> +
> +	error = nvme_auth_negotiate(ctrl, 0);
> +	if (error < 0)
> +		return error;
> +
> +	error = nvme_auth_wait(ctrl, 0);
> +	if (error < 0)
> +		return error;
> +
> +	return count;
> +}
> +static DEVICE_ATTR_RW(tls_configured_key);
>   
>   static ssize_t tls_keyring_show(struct device *dev,
>   		struct device_attribute *attr, char *buf)

Errm. Why 'configured_key'?

The configured_key sysfs attribute is a representation of the --tls-key
attribute when calling 'nvme connect', which in itself should be used
for debugging purposes only. And as such it really cannot be modified.

Please use the 'tls_key' attribute (which holds the negotiated key,
and is available always).

Cheers,

Hannes
--
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@xxxxxxx                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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