From 71881fffd68b6f9e69786ffa42592e64d490328e Mon Sep 17 00:00:00 2001
From: Bowgo Tsai <bowgotsai@google.com>
Date: Tue, 25 Apr 2017 13:09:47 +0800
Subject: [PATCH] init: fix first stage mount failure when two fstab entries
 have verity_loc

The previous check is incorrect because it compares the basename of
previous verity_loc with the full path of current verity_loc.

Changes it to compare the full device file path instead of just the basename
of verity_loc. This can catch the case of two different verity_loc
values with the same basename, e.g.,

  - verify=/dev/block/platform/SOC.0/by-name/metadata
  - verify=/dev/block/platform/SOC.1/by-name/metadata

Bug: 37413399
Bug: 37619597
Test: first stage mount /system and /vendor with the following fs_mgr_flags on bullhead
        - wait,verify=/dev/block/platform/soc.0/f9824900.sdhci/by-name/metadataa
Test: first stage mount /system and /vendor with different verity_loc values
      on bullhead, checks it bails out
Change-Id: I017c8bd9f0790d45e08e57df9a2878e4f62c5f9c
---
 init/init_first_stage.cpp | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/init/init_first_stage.cpp b/init/init_first_stage.cpp
index 0bacd9ca9..43f1c1504 100644
--- a/init/init_first_stage.cpp
+++ b/init/init_first_stage.cpp
@@ -232,7 +232,7 @@ bool FirstStageMount::MountPartitions() {
 
 bool FirstStageMountVBootV1::GetRequiredDevices(std::set<std::string>* out_devices_partition_names,
                                                 bool* out_need_dm_verity) {
-    std::string meta_partition;
+    std::string verity_loc_device;
     *out_need_dm_verity = false;
 
     for (auto fstab_rec : mount_fstab_recs_) {
@@ -245,29 +245,28 @@ bool FirstStageMountVBootV1::GetRequiredDevices(std::set<std::string>* out_devic
         if (fs_mgr_is_verified(fstab_rec)) {
             *out_need_dm_verity = true;
         }
-        // Checks if verity metadata is on a separate partition and get partition
-        // name from the end of the ->verity_loc path. Verity state is not partition
-        // specific, so there must be only one additional partition that carries
-        // verity state.
+        // Checks if verity metadata is on a separate partition. Note that it is
+        // not partition specific, so there must be only one additional partition
+        // that carries verity state.
         if (fstab_rec->verity_loc) {
-            if (meta_partition.empty()) {
-                meta_partition = basename(fstab_rec->verity_loc);
-            } else if (meta_partition != fstab_rec->verity_loc) {
-                LOG(ERROR) << "More than one meta partition found: " << meta_partition << ", "
-                           << basename(fstab_rec->verity_loc);
+            if (verity_loc_device.empty()) {
+                verity_loc_device = fstab_rec->verity_loc;
+            } else if (verity_loc_device != fstab_rec->verity_loc) {
+                LOG(ERROR) << "More than one verity_loc found: " << verity_loc_device << ", "
+                           << fstab_rec->verity_loc;
                 return false;
             }
         }
     }
 
-    // Includes those fstab partitions and meta_partition (if any).
+    // Includes the partition names of fstab records and verity_loc_device (if any).
     // Notes that fstab_rec->blk_device has A/B suffix updated by fs_mgr when A/B is used.
     for (auto fstab_rec : mount_fstab_recs_) {
         out_devices_partition_names->emplace(basename(fstab_rec->blk_device));
     }
 
-    if (!meta_partition.empty()) {
-        out_devices_partition_names->emplace(std::move(meta_partition));
+    if (!verity_loc_device.empty()) {
+        out_devices_partition_names->emplace(basename(verity_loc_device.c_str()));
     }
 
     return true;