nfit: fail DSMs that return non-zero status by default

For the DSMs where the kernel knows the format of the output buffer and
originates those DSMs from within the kernel, return -EIO for any
non-zero status.  If the BIOS is indicating a status that we do not know
how to handle, fail the DSM.

Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 28 insertions, 20 deletions

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 80cc7c089a15..e1d5ea6d5e40 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -94,54 +94,50 @@ static struct acpi_device *to_acpi_dev(struct acpi_nfit_desc *acpi_desc)
         return to_acpi_device(acpi_desc->dev);
 }
 
-static int xlat_status(void *buf, unsigned int cmd)
+static int xlat_status(void *buf, unsigned int cmd, u32 status)
 {
         struct nd_cmd_clear_error *clear_err;
         struct nd_cmd_ars_status *ars_status;
-        struct nd_cmd_ars_start *ars_start;
-        struct nd_cmd_ars_cap *ars_cap;
         u16 flags;
 
         switch (cmd) {
         case ND_CMD_ARS_CAP:
-                ars_cap = buf;
-                if ((ars_cap->status & 0xffff) == NFIT_ARS_CAP_NONE)
+                if ((status & 0xffff) == NFIT_ARS_CAP_NONE)
                         return -ENOTTY;
 
                 /* Command failed */
-                if (ars_cap->status & 0xffff)
+                if (status & 0xffff)
                         return -EIO;
 
                 /* No supported scan types for this range */
                 flags = ND_ARS_PERSISTENT | ND_ARS_VOLATILE;
-                if ((ars_cap->status >> 16 & flags) == 0)
+                if ((status >> 16 & flags) == 0)
                         return -ENOTTY;
                 break;
         case ND_CMD_ARS_START:
-                ars_start = buf;
                 /* ARS is in progress */
-                if ((ars_start->status & 0xffff) == NFIT_ARS_START_BUSY)
+                if ((status & 0xffff) == NFIT_ARS_START_BUSY)
                         return -EBUSY;
 
                 /* Command failed */
-                if (ars_start->status & 0xffff)
+                if (status & 0xffff)
                         return -EIO;
                 break;
         case ND_CMD_ARS_STATUS:
                 ars_status = buf;
                 /* Command failed */
-                if (ars_status->status & 0xffff)
+                if (status & 0xffff)
                         return -EIO;
                 /* Check extended status (Upper two bytes) */
-                if (ars_status->status == NFIT_ARS_STATUS_DONE)
+                if (status == NFIT_ARS_STATUS_DONE)
                         return 0;
 
                 /* ARS is in progress */
-                if (ars_status->status == NFIT_ARS_STATUS_BUSY)
+                if (status == NFIT_ARS_STATUS_BUSY)
                         return -EBUSY;
 
                 /* No ARS performed for the current boot */
-                if (ars_status->status == NFIT_ARS_STATUS_NONE)
+                if (status == NFIT_ARS_STATUS_NONE)
                         return -EAGAIN;
 
                 /*
@@ -149,19 +145,19 @@ static int xlat_status(void *buf, unsigned int cmd)
                  * agent wants the scan to stop.  If we didn't overflow
                  * then just continue with the returned results.
                  */
-                if (ars_status->status == NFIT_ARS_STATUS_INTR) {
+                if (status == NFIT_ARS_STATUS_INTR) {
                         if (ars_status->flags & NFIT_ARS_F_OVERFLOW)
                                 return -ENOSPC;
                         return 0;
                 }
 
                 /* Unknown status */
-                if (ars_status->status >> 16)
+                if (status >> 16)
                         return -EIO;
                 break;
         case ND_CMD_CLEAR_ERROR:
                 clear_err = buf;
-                if (clear_err->status & 0xffff)
+                if (status & 0xffff)
                         return -EIO;
                 if (!clear_err->cleared)
                         return -EIO;
@@ -172,6 +168,9 @@ static int xlat_status(void *buf, unsigned int cmd)
                 break;
         }
 
+        /* all other non-zero status results in an error */
+        if (status)
+                return -EIO;
         return 0;
 }
 
@@ -186,10 +185,10 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
         struct nd_cmd_pkg *call_pkg = NULL;
         const char *cmd_name, *dimm_name;
         unsigned long cmd_mask, dsm_mask;
+        u32 offset, fw_status = 0;
         acpi_handle handle;
         unsigned int func;
         const u8 *uuid;
-        u32 offset;
         int rc, i;
 
         func = cmd;
@@ -317,6 +316,15 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
                                 out_obj->buffer.pointer + offset, out_size);
                 offset += out_size;
         }
+
+        /*
+         * Set fw_status for all the commands with a known format to be
+         * later interpreted by xlat_status().
+         */
+        if (i >= 1 && ((cmd >= ND_CMD_ARS_CAP && cmd <= ND_CMD_CLEAR_ERROR)
+                        || (cmd >= ND_CMD_SMART && cmd <= ND_CMD_VENDOR)))
+                fw_status = *(u32 *) out_obj->buffer.pointer;
+
         if (offset + in_buf.buffer.length < buf_len) {
                 if (i >= 1) {
                         /*
@@ -325,7 +333,7 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
                          */
                         rc = buf_len - offset - in_buf.buffer.length;
                         if (cmd_rc)
-                                *cmd_rc = xlat_status(buf, cmd);
+                                *cmd_rc = xlat_status(buf, cmd, fw_status);
                 } else {
                         dev_err(dev, "%s:%s underrun cmd: %s buf_len: %d out_len: %d\n",
                                         __func__, dimm_name, cmd_name, buf_len,
@@ -335,7 +343,7 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
         } else {
                 rc = 0;
                 if (cmd_rc)
-                        *cmd_rc = xlat_status(buf, cmd);
+                        *cmd_rc = xlat_status(buf, cmd, fw_status);
         }
 
  out: