avb: Allow system partition to be absent
On devices with dynamic partitions,'system' partition might not exist.
Therefore, we should not add root=$(ANDROID_SYSTEM_PARTUUID) in kernel
cmdline and resolve it for devices without system partition.
Bug: 119551429
Test: m libavb_host_unittest &&
../../out/host/linux-x86/nativetest64/libavb_host_unittest/libavb_host_unittest
Git-repo: https://source.codeaurora.org/quic/la/platform/external/avb
Git-Commit: 5abd6bc2578968d24406d834471adfd995a0c2e9
Change-Id: I99d56c103a2ca562574db38bfce22a61a0088484
diff --git a/platform/msm_shared/avb/libavb/avb_slot_verify.c b/platform/msm_shared/avb/libavb/avb_slot_verify.c
index e0049e6..8d0db6d 100644
--- a/platform/msm_shared/avb/libavb/avb_slot_verify.c
+++ b/platform/msm_shared/avb/libavb/avb_slot_verify.c
@@ -1276,6 +1276,35 @@
return ret;
}
+static bool has_system_partition(AvbOps* ops, const char* ab_suffix) {
+ char part_name[PART_NAME_MAX_SIZE];
+ char* system_part_name = "system";
+ char guid_buf[37];
+ AvbIOResult io_ret;
+
+ if (!avb_str_concat(part_name,
+ sizeof part_name,
+ system_part_name,
+ avb_strlen(system_part_name),
+ ab_suffix,
+ avb_strlen(ab_suffix))) {
+ avb_error("System partition name and suffix does not fit.\n");
+ return false;
+ }
+
+ io_ret = ops->get_unique_guid_for_partition(
+ ops, part_name, guid_buf, sizeof guid_buf);
+ if (io_ret == AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION) {
+ avb_debug("No system partition.\n");
+ return false;
+ } else if (io_ret != AVB_IO_RESULT_OK) {
+ avb_error("Error getting unique GUID for system partition.\n");
+ return false;
+ }
+
+ return true;
+}
+
AvbSlotVerifyResult avb_slot_verify(AvbOps* ops,
const char* const* requested_partitions,
const char* ab_suffix,
@@ -1377,11 +1406,16 @@
* that the system partition is mounted.
*/
avb_assert(slot_data->cmdline == NULL);
- slot_data->cmdline =
- avb_strdup("root=PARTUUID=$(ANDROID_SYSTEM_PARTUUID)");
- if (slot_data->cmdline == NULL) {
- ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
- goto fail;
+ // Devices with dynamic partitions won't have system partition.
+ // Instead, it has a large super partition to accommodate *.img files.
+ // See b/119551429 for details.
+ if (has_system_partition(ops, ab_suffix)) {
+ slot_data->cmdline =
+ avb_strdup("root=PARTUUID=$(ANDROID_SYSTEM_PARTUUID)");
+ if (slot_data->cmdline == NULL) {
+ ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
+ goto fail;
+ }
}
} else {
/* Add options - any failure in append_options() is either an