ACPI, APEI, HEST Fix the unsuitable usage of platform_data

platform_data in hest_parse_ghes() is used for saving the address of entry
information of erst_tab. When the device is failed to be added, platform_data
will be freed by platform_device_put(). But the value saved in platform_data
should not be freed here. If it is done, it will make system panic.

So I think platform_data should save the address of allocated memory
which saves entry information of erst_tab.

This patch fixed it and I confirmed it on x86_64 next-tree.

v2:
    Transport the pointer of hest_hdr to platform_data using
    platform_device_add_data()

Signed-off-by: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 8 insertions, 5 deletions

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 385a6059714a..0d505e59214d 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -302,7 +302,7 @@ static int __devinit ghes_probe(struct platform_device *ghes_dev)
         struct ghes *ghes = NULL;
         int rc = -EINVAL;
 
-        generic = ghes_dev->dev.platform_data;
+        generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data;
         if (!generic->enabled)
                 return -ENODEV;
 
diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c
index 343168d18266..1a3508a7fe03 100644
--- a/drivers/acpi/apei/hest.c
+++ b/drivers/acpi/apei/hest.c
@@ -137,20 +137,23 @@ static int hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
 
 static int hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
 {
-        struct acpi_hest_generic *generic;
         struct platform_device *ghes_dev;
         struct ghes_arr *ghes_arr = data;
         int rc;
 
         if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR)
                 return 0;
-        generic = (struct acpi_hest_generic *)hest_hdr;
-        if (!generic->enabled)
+
+        if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
                 return 0;
         ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
         if (!ghes_dev)
                 return -ENOMEM;
-        ghes_dev->dev.platform_data = generic;
+
+        rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
+        if (rc)
+                goto err;
+
         rc = platform_device_add(ghes_dev);
         if (rc)
                 goto err;