9:14 a.m.
Right now when debug is enabled, we dump the command buffer
indescriminately. This exposes the clear text payload for security DSMs.
Introducing a kernel config to only dump the payload if the config option
is turned on so the production kernels can leave this option off and not
expose the passphrases.
Signed-off-by: Dave Jiang <dave.jiang(a)intel.com>
---
drivers/acpi/nfit/Kconfig | 7 +++++++
drivers/acpi/nfit/core.c | 24 +++++++++++++++++++++---
2 files changed, 28 insertions(+), 3 deletions(-)
diff --git a/drivers/acpi/nfit/Kconfig b/drivers/acpi/nfit/Kconfig
index f7c57e33499e..a0a8eabda2e8 100644
--- a/drivers/acpi/nfit/Kconfig
+++ b/drivers/acpi/nfit/Kconfig
@@ -13,3 +13,10 @@ config ACPI_NFIT
To compile this driver as a module, choose M here:
the module will be called nfit.
+
+config NFIT_SECURITY_DEBUG
+ bool "Turn on debugging for NVDIMM security features"
+ depends on ACPI_NFIT
+ help
+ Turning on debug output for NVDIMM security DSM commands. This
+ should not be turned on on a production kernel.
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 867e6fea3737..baaf5308de35 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -405,6 +405,21 @@ static u8 nfit_dsm_revid(unsigned family, unsigned func)
return id;
}
+static bool is_security_cmd(unsigned int cmd, unsigned int func,
+ unsigned int family)
+{
+ if (cmd != ND_CMD_CALL)
+ return false;
+
+ if (family == NVDIMM_FAMILY_INTEL) {
+ if (func >= NVDIMM_INTEL_GET_SECURITY_STATE &&
+ func <= NVDIMM_INTEL_MASTER_SECURE_ERASE)
+ return true;
+ }
+
+ return false;
+}
+
int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc)
{
@@ -489,9 +504,12 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct
nvdimm *nvdimm,
dev_dbg(dev, "%s cmd: %d: func: %d input length: %d\n",
dimm_name, cmd, func, in_buf.buffer.length);
- print_hex_dump_debug("nvdimm in ", DUMP_PREFIX_OFFSET, 4, 4,
- in_buf.buffer.pointer,
- min_t(u32, 256, in_buf.buffer.length), true);
+ if ((call_pkg && !is_security_cmd(cmd, func, call_pkg->nd_family)) ||
+ IS_ENABLED(CONFIG_NFIT_SECURITY_DEBUG)) {
+ print_hex_dump_debug("nvdimm in ", DUMP_PREFIX_OFFSET, 4, 4,
+ in_buf.buffer.pointer,
+ min_t(u32, 256, in_buf.buffer.length), true);
+ }
/* call the BIOS, prefer the named methods over _DSM if available */
if (nvdimm && cmd == ND_CMD_GET_CONFIG_SIZE