From 37833fb7989a9d3c3e26354e6878e682c340d718 Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Thu, 6 Dec 2018 09:14:08 -0800 Subject: acpi/nfit, libnvdimm: Add freeze security support to Intel nvdimm Add support for freeze security on Intel nvdimm. This locks out any changes to security for the DIMM until a hard reset of the DIMM is performed. This is triggered by writing "freeze" to the generic nvdimm/nmemX "security" sysfs attribute. Signed-off-by: Dave Jiang Co-developed-by: Dan Williams Signed-off-by: Dan Williams --- drivers/nvdimm/dimm_devs.c | 66 ++++++++++++++++++++++++++++++++++++++++++++-- drivers/nvdimm/nd-core.h | 1 + 2 files changed, 65 insertions(+), 2 deletions(-) (limited to 'drivers/nvdimm') diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c index 9609b671311b..8e0bd2ce4dd0 100644 --- a/drivers/nvdimm/dimm_devs.c +++ b/drivers/nvdimm/dimm_devs.c @@ -390,7 +390,48 @@ static ssize_t security_show(struct device *dev, return -ENOTTY; } -static DEVICE_ATTR_RO(security); + +static ssize_t __security_store(struct device *dev, const char *buf, size_t len) +{ + struct nvdimm *nvdimm = to_nvdimm(dev); + ssize_t rc; + + if (atomic_read(&nvdimm->busy)) + return -EBUSY; + + if (sysfs_streq(buf, "freeze")) { + dev_dbg(dev, "freeze\n"); + rc = nvdimm_security_freeze(nvdimm); + } else + return -EINVAL; + + if (rc == 0) + rc = len; + return rc; + +} + +static ssize_t security_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) + +{ + ssize_t rc; + + /* + * Require all userspace triggered security management to be + * done while probing is idle and the DIMM is not in active use + * in any region. + */ + device_lock(dev); + nvdimm_bus_lock(dev); + wait_nvdimm_bus_probe_idle(dev); + rc = __security_store(dev, buf, len); + nvdimm_bus_unlock(dev); + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RW(security); static struct attribute *nvdimm_attributes[] = { &dev_attr_state.attr, @@ -410,7 +451,10 @@ static umode_t nvdimm_visible(struct kobject *kobj, struct attribute *a, int n) return a->mode; if (nvdimm->sec.state < 0) return 0; - return a->mode; + /* Are there any state mutation ops? */ + if (nvdimm->sec.ops->freeze) + return a->mode; + return 0444; } struct attribute_group nvdimm_attribute_group = { @@ -462,6 +506,24 @@ struct nvdimm *__nvdimm_create(struct nvdimm_bus *nvdimm_bus, } EXPORT_SYMBOL_GPL(__nvdimm_create); +int nvdimm_security_freeze(struct nvdimm *nvdimm) +{ + int rc; + + WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev)); + + if (!nvdimm->sec.ops || !nvdimm->sec.ops->freeze) + return -EOPNOTSUPP; + + if (nvdimm->sec.state < 0) + return -EIO; + + rc = nvdimm->sec.ops->freeze(nvdimm); + nvdimm->sec.state = nvdimm_security_state(nvdimm); + + return rc; +} + int alias_dpa_busy(struct device *dev, void *data) { resource_size_t map_end, blk_start, new; diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h index 1919f5c0d581..15eff40f55f6 100644 --- a/drivers/nvdimm/nd-core.h +++ b/drivers/nvdimm/nd-core.h @@ -56,6 +56,7 @@ static inline enum nvdimm_security_state nvdimm_security_state( return nvdimm->sec.ops->state(nvdimm); } +int nvdimm_security_freeze(struct nvdimm *nvdimm); /** * struct blk_alloc_info - tracking info for BLK dpa scanning -- cgit