core/pel: Validate 'system-id' DT property before using

Platforms like mambo doesn't populate 'system-id' DT property. Validate
these properties before using.

Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
[stewart@linux.vnet.ibm.com, memset(0) for not found dt props, fix unit test]
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

2 files changed, 33 insertions, 9 deletions

diff --git a/core/pel.c b/core/pel.c
index 5df3e91..d8c4b98 100644
--- a/core/pel.c
+++ b/core/pel.c
@@ -9,6 +9,8 @@
 static void create_mtms_section(struct errorlog *elog_data,
 					char *pel_buffer, int *pel_offset)
 {
+	const struct dt_property *p;
+
 	struct opal_mtms_section *mtms = (struct opal_mtms_section *)
 				(pel_buffer + *pel_offset);
 
@@ -20,10 +22,14 @@ static void create_mtms_section(struct errorlog *elog_data,
 
 	memset(mtms->model, 0x00, sizeof(mtms->model));
 	memcpy(mtms->model, dt_prop_get(dt_root, "model"), OPAL_SYS_MODEL_LEN);
+
 	memset(mtms->serial_no, 0x00, sizeof(mtms->serial_no));
+	p = dt_find_property(dt_root, "system-id");
+	if (p)
+		memcpy(mtms->serial_no, p->prop, OPAL_SYS_SERIAL_LEN);
+	else
+		memset(mtms->serial_no, 0, OPAL_SYS_SERIAL_LEN);
 
-	memcpy(mtms->serial_no, dt_prop_get(dt_root, "system-id"),
-						 OPAL_SYS_SERIAL_LEN);
 	*pel_offset += MTMS_SECTION_SIZE;
 }
 
@@ -32,6 +38,7 @@ static void create_extended_header_section(struct errorlog *elog_data,
 					char *pel_buffer, int *pel_offset)
 {
 	const char  *opalmodel = NULL;
+	const struct dt_property *p;
 	uint64_t extd_time;
 
 	struct opal_extended_header_section *extdhdr =
@@ -49,8 +56,11 @@ static void create_extended_header_section(struct errorlog *elog_data,
 	memcpy(extdhdr->model, opalmodel, OPAL_SYS_MODEL_LEN);
 
 	memset(extdhdr->serial_no, 0x00, sizeof(extdhdr->serial_no));
-	memcpy(extdhdr->serial_no, dt_prop_get(dt_root, "system-id"),
-							OPAL_SYS_SERIAL_LEN);
+	p = dt_find_property(dt_root, "system-id");
+	if (p)
+		memcpy(extdhdr->serial_no, p->prop, OPAL_SYS_SERIAL_LEN);
+	else
+		memset(extdhdr->serial_no, 0, OPAL_SYS_SERIAL_LEN);
 
 	memset(extdhdr->opal_release_version, 0x00,
 				sizeof(extdhdr->opal_release_version));
diff --git a/core/test/run-pel.c b/core/test/run-pel.c
index ab1fa05..433842b 100644
--- a/core/test/run-pel.c
+++ b/core/test/run-pel.c
@@ -25,6 +25,7 @@
 #include <assert.h>
 #include <pel.h>
 #include <errorlog.h>
+#include <device.h>
 
 #define TEST_ERROR 0x1234
 #define TEST_SUBSYS 0x5678
@@ -33,14 +34,24 @@ DEFINE_LOG_ENTRY(TEST_ERROR, OPAL_PLATFORM_ERR_EVT, TEST_SUBSYS,
 			OPAL_PLATFORM_FIRMWARE, OPAL_INFO,
 			OPAL_NA);
 
+/* Override this for testing. */
+#define is_rodata(p) fake_is_rodata(p)
+
+char __rodata_start[16];
+#define __rodata_end (__rodata_start + sizeof(__rodata_start))
+
+static inline bool fake_is_rodata(const void *p)
+{
+	return ((char *)p >= __rodata_start && (char *)p < __rodata_end);
+}
+
+#define zalloc(bytes) calloc((bytes), 1)
+
+#include "../device.c"
 #include "../pel.c"
 
 struct dt_node *dt_root = NULL;
 char dt_prop[] = "DUMMY DT PROP";
-const void *dt_prop_get(const struct dt_node *node __unused, const char *prop __unused)
-{
-	return dt_prop;
-}
 
 int rtc_cache_get_datetime(uint32_t *year_month_day,
 			   uint64_t *hour_minute_second_millisecond)
@@ -60,6 +71,9 @@ int main(void)
 	char *buffer;
 	struct elog_user_data_section *tmp;
 
+	dt_root = dt_new_root("");
+	dt_add_property_string(dt_root, "model", "run-pel-unittest");
+
 	elog = malloc(sizeof(struct errorlog));
 	pel_buf = malloc(PEL_MIN_SIZE + 4);
 	assert(elog);
@@ -96,7 +110,7 @@ int main(void)
 	size = pel_size(elog);
 	pel_buf = realloc(pel_buf, size);
 	assert(pel_buf);
-	
+
 	buffer = elog->user_data_dump + elog->user_section_size;
 	tmp = (struct elog_user_data_section *)buffer;
 	tmp->tag = 0x44455343;  /* ASCII of DESC */