[patch v2] crypto: ccp - Fix SEV_VERSION_GREATER_OR_EQUAL

From: David Rientjes
Date: Fri Jul 12 2019 - 16:42:05 EST


SEV_VERSION_GREATER_OR_EQUAL() will fail if upgrading from 2.2 to 3.1, for
example, because the minor version is not equal to or greater than the
major.

Fix this and move to a static inline function for appropriate type
checking.

Fixes: edd303ff0e9e ("crypto: ccp - Add DOWNLOAD_FIRMWARE SEV command")
Reported-by: Cfir Cohen <cfir@xxxxxxxxxx>
Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx>
---
v2: no need to check api_major >= maj after checking api_major > maj
per Thomas

drivers/crypto/ccp/psp-dev.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
--- a/drivers/crypto/ccp/psp-dev.c
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -24,10 +24,6 @@
#include "sp-dev.h"
#include "psp-dev.h"

-#define SEV_VERSION_GREATER_OR_EQUAL(_maj, _min) \
- ((psp_master->api_major) >= _maj && \
- (psp_master->api_minor) >= _min)
-
#define DEVICE_NAME "sev"
#define SEV_FW_FILE "amd/sev.fw"
#define SEV_FW_NAME_SIZE 64
@@ -47,6 +43,15 @@ MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during
static bool psp_dead;
static int psp_timeout;

+static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
+{
+ if (psp_master->api_major > maj)
+ return true;
+ if (psp_master->api_major == maj && psp_master->api_minor >= min)
+ return true;
+ return false;
+}
+
static struct psp_device *psp_alloc_struct(struct sp_device *sp)
{
struct device *dev = sp->dev;
@@ -588,7 +593,7 @@ static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
int ret;

/* SEV GET_ID is available from SEV API v0.16 and up */
- if (!SEV_VERSION_GREATER_OR_EQUAL(0, 16))
+ if (!sev_version_greater_or_equal(0, 16))
return -ENOTSUPP;

if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
@@ -651,7 +656,7 @@ static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
int ret;

/* SEV GET_ID available from SEV API v0.16 and up */
- if (!SEV_VERSION_GREATER_OR_EQUAL(0, 16))
+ if (!sev_version_greater_or_equal(0, 16))
return -ENOTSUPP;

/* SEV FW expects the buffer it fills with the ID to be
@@ -1053,7 +1058,7 @@ void psp_pci_init(void)
psp_master->sev_state = SEV_STATE_UNINIT;
}

- if (SEV_VERSION_GREATER_OR_EQUAL(0, 15) &&
+ if (sev_version_greater_or_equal(0, 15) &&
sev_update_firmware(psp_master->dev) == 0)
sev_get_api_version();