aoc: gracefully handle coredump corrupt caseandroid-u-qpr2-beta-2_r0.7android-u-qpr2-beta-2_r0.5android-u-qpr2-beta-2_r0.4android-u-qpr2-beta-2_r0.3android-u-qpr2-beta-2_r0.2android-u-qpr2-beta-2_r0.1

Test: on device
Bug: 307383094
Change-Id: Id474c099fa8392e3379b7a2a8861bf508951352a
Signed-off-by: Alex Iacobucci <alexiacobucci@google.com>

1 files changed, 24 insertions, 66 deletions

diff --git a/aoc.c b/aoc.c
index e9481b7..21e0cf7 100644
--- a/aoc.c
+++ b/aoc.c
@@ -1658,21 +1658,6 @@ void aoc_remove_map_handler(struct aoc_service_dev *dev)
 }
 EXPORT_SYMBOL_GPL(aoc_remove_map_handler);
 
-static struct aoc_section_header *find_ramdump_section(struct aoc_ramdump_header
-						*ramdump_header, int section_type)
-{
-	int i;
-
-	if (ramdump_header->num_sections != RAMDUMP_NUM_SECTIONS)
-		return NULL;
-
-	for (i = 0; i < ramdump_header->num_sections; i++)
-		if (ramdump_header->sections[i].type == section_type)
-			return &ramdump_header->sections[i];
-
-	return NULL;
-}
-
 static void aoc_watchdog(struct work_struct *work)
 {
 	struct aoc_prvdata *prvdata =
@@ -1696,9 +1681,8 @@ static void aoc_watchdog(struct work_struct *work)
 	int sscd_rc;
 	char crash_info[RAMDUMP_SECTION_CRASH_INFO_SIZE];
 	int restart_rc;
-	bool ap_reset = false, invalid_magic;
-	struct aoc_section_header *crash_info_section =
-		find_ramdump_section(ramdump_header, SECTION_TYPE_CRASH_INFO);
+	bool ap_reset = false, valid_magic;
+	struct aoc_section_header *crash_info_section;
 
 	prvdata->total_restarts++;
 
@@ -1747,18 +1731,27 @@ static void aoc_watchdog(struct work_struct *work)
 
 	ramdump_timeout = jiffies + (5 * HZ);
 	while (time_before(jiffies, ramdump_timeout)) {
-		if (ramdump_header->valid)
+		valid_magic = memcmp(ramdump_header, RAMDUMP_MAGIC, sizeof(RAMDUMP_MAGIC)) == 0;
+		if (ramdump_header->valid == 1 && valid_magic)
 			break;
 		msleep(100);
 	}
 
-	if (!ramdump_header->valid) {
-		dev_err(prvdata->dev, "aoc coredump timed out, coredump only contains DRAM\n");
+	crash_info_section = &ramdump_header->sections[RAMDUMP_SECTION_CRASH_INFO_INDEX];
+	if (crash_info_section->type != SECTION_TYPE_CRASH_INFO)
+		crash_info_section = NULL;
+
+	if (!(ramdump_header->valid == 1) || !valid_magic) {
+		if (!(ramdump_header->valid == 1))
+			dev_info(prvdata->dev, "aoc coredump timed out, coredump only contains DRAM\n");
+		if (!valid_magic)
+			dev_info(prvdata->dev, "aoc coredump has invalid magic\n");
+
 		if (crash_info_section) {
 			const char *crash_reason = (const char *)ramdump_header +
 				crash_info_section->offset;
-			bool crash_reason_valid = (strnlen(crash_reason,
-				sizeof(crash_info)) != 0);
+			bool crash_reason_valid = crash_reason < (char *)prvdata->dram_virt +
+				prvdata->dram_size && crash_reason[0] != 0;
 
 			snprintf(crash_info, sizeof(crash_info),
 				"AoC watchdog : %s (incomplete %u:%u)",
@@ -1772,31 +1765,17 @@ static void aoc_watchdog(struct work_struct *work)
 		}
 	}
 
-	invalid_magic = memcmp(ramdump_header, RAMDUMP_MAGIC, sizeof(RAMDUMP_MAGIC));
-	if (ramdump_header->valid && invalid_magic) {
-		dev_err(prvdata->dev,
-			"aoc coredump possibly failed: invalid magic\n");
-		if (crash_info_section) {
+	if (ramdump_header->valid == 1 && valid_magic) {
+		if (crash_info_section && crash_info_section->flags & RAMDUMP_FLAG_VALID) {
 			const char *crash_reason = (const char *)ramdump_header +
 				crash_info_section->offset;
-			/* Check that offset was not corrupted and that we are not reading
-				random bytes */
-			bool crash_reason_valid = crash_reason < (char *)prvdata->dram_virt +
-				prvdata->dram_size && crash_reason[0] != 0;
-
-			if (crash_reason_valid) {
-				snprintf(crash_info, sizeof(crash_info),
-					"AoC watchdog : coredump corrupt [%s]", crash_reason);
-			} else {
-				snprintf(crash_info, sizeof(crash_info),
-					"AoC watchdog : coredump corrupt (incomplete %u:%u)",
-					ramdump_header->breadcrumbs[0],
-					ramdump_header->breadcrumbs[1]);
-			}
+			dev_info(prvdata->dev,
+				"aoc coredump has valid coredump header, crash reason [%s]", crash_reason);
+			strscpy(crash_info, crash_reason, sizeof(crash_info));
 		} else {
-			dev_err(prvdata->dev,
-				"could not find crash info section in aoc coredump header");
-			strscpy(crash_info, "AoC Watchdog : coredump corrupt",
+			dev_info(prvdata->dev,
+				"aoc coredump has valid coredump header, but invalid crash reason");
+			strscpy(crash_info, "AoC Watchdog : invalid crash info",
 				sizeof(crash_info));
 		}
 	}
@@ -1824,27 +1803,6 @@ static void aoc_watchdog(struct work_struct *work)
 		sscd_info.segs[0].addr = prvdata->dram_virt;
 	}
 
-	if (ramdump_header->valid && !invalid_magic) {
-
-		if (crash_info_section && crash_info_section->flags & RAMDUMP_FLAG_VALID) {
-			const char *crash_reason = (const char *)ramdump_header +
-				crash_info_section->offset;
-								bool crash_reason_valid = crash_reason < (char *)prvdata->dram_virt +
-				prvdata->dram_size && crash_reason[0] != 0;
-
-		if (crash_reason_valid)
-			pr_err(">>> valid!!");
-		else
-			pr_err(">>> invalid!!!");
-		dev_info(prvdata->dev, "aoc coredump has valid coredump header, crash reason [%s]",
-				crash_reason);
-			strscpy(crash_info, crash_reason, sizeof(crash_info));
-		} else {
-			dev_info(prvdata->dev, "aoc coredump has valid coredump header, but invalid crash reason");
-			strscpy(crash_info, "AoC Watchdog : invalid crash info",
-				sizeof(crash_info));
-		}
-	}
 
 	if (ap_reset) {
 		/* Prefer the user specified reason */