commit 7082f6880890af965c55217e19bfe787e07e8c9c
author David Anderson <dvander@google.com> Mon Mar 18 19:17:11 2019 -0700
committer David Anderson <dvander@google.com> Fri Mar 22 13:47:27 2019 -0700
tree c3ed43c6271140793145191ee6e284a75f42f889
parent ee725f610f23503aa41c0b7f2615c836f7640fc7

Fix device mapper name clashes on non-A/B devices.

Bug: 123666267
Test: sysfs reports -verity suffix for verity node names
Change-Id: I07fe428ce86209825e39a0ebf7b4d622b93cc81b

fs_mgr/fs_mgr.cpp

diff --git a/fs_mgr/fs_mgr.cpp b/fs_mgr/fs_mgr.cpp
index ba6b9eb..045bb48 100644
--- a/fs_mgr/fs_mgr.cpp
+++ b/fs_mgr/fs_mgr.cpp
@@ -1602,14 +1602,6 @@
     return true;
 }
 
-std::string fs_mgr_get_verity_device_name(const FstabEntry& entry) {
-    if (entry.mount_point == "/") {
-        // In AVB, the dm device name is vroot instead of system.
-        return entry.fs_mgr_flags.avb ? "vroot" : "system";
-    }
-    return Basename(entry.mount_point);
-}
-
 bool fs_mgr_is_verity_enabled(const FstabEntry& entry) {
     if (!entry.fs_mgr_flags.verify && !entry.fs_mgr_flags.avb) {
         return false;
@@ -1617,7 +1609,7 @@
 
     DeviceMapper& dm = DeviceMapper::Instance();
 
-    std::string mount_point = fs_mgr_get_verity_device_name(entry);
+    std::string mount_point = GetVerityDeviceName(entry);
     if (dm.GetState(mount_point) == DmDeviceState::INVALID) {
         return false;
     }
@@ -1646,7 +1638,7 @@
     }
 
     DeviceMapper& dm = DeviceMapper::Instance();
-    std::string device = fs_mgr_get_verity_device_name(entry);
+    std::string device = GetVerityDeviceName(entry);
 
     std::vector<DeviceMapper::TargetInfo> table;
     if (dm.GetState(device) == DmDeviceState::INVALID || !dm.GetTableInfo(device, &table)) {

fs_mgr/fs_mgr_fstab.cpp

diff --git a/fs_mgr/fs_mgr_fstab.cpp b/fs_mgr/fs_mgr_fstab.cpp
index 2f1e41f..f6f6f50 100644
--- a/fs_mgr/fs_mgr_fstab.cpp
+++ b/fs_mgr/fs_mgr_fstab.cpp
@@ -768,6 +768,17 @@
     return system;
 }
 
+std::string GetVerityDeviceName(const FstabEntry& entry) {
+    std::string base_device;
+    if (entry.mount_point == "/") {
+        // In AVB, the dm device name is vroot instead of system.
+        base_device = entry.fs_mgr_flags.avb ? "vroot" : "system";
+    } else {
+        base_device = android::base::Basename(entry.mount_point);
+    }
+    return base_device + "-verity";
+}
+
 }  // namespace fs_mgr
 }  // namespace android
 

fs_mgr/include_fstab/fstab/fstab.h

diff --git a/fs_mgr/include_fstab/fstab/fstab.h b/fs_mgr/include_fstab/fstab/fstab.h
index e811447..88da41d 100644
--- a/fs_mgr/include_fstab/fstab/fstab.h
+++ b/fs_mgr/include_fstab/fstab/fstab.h
@@ -107,5 +107,10 @@
 
 std::set<std::string> GetBootDevices();
 
+// Return the name of the dm-verity device for the given fstab entry. This does
+// not check whether the device is valid or exists; it merely returns the
+// expected name.
+std::string GetVerityDeviceName(const FstabEntry& entry);
+
 }  // namespace fs_mgr
 }  // namespace android

fs_mgr/libfs_avb/avb_util.cpp

diff --git a/fs_mgr/libfs_avb/avb_util.cpp b/fs_mgr/libfs_avb/avb_util.cpp
index f4e4d4e..d9650f3 100644
--- a/fs_mgr/libfs_avb/avb_util.cpp
+++ b/fs_mgr/libfs_avb/avb_util.cpp
@@ -105,14 +105,15 @@
     table.set_readonly(true);
 
     const std::string mount_point(Basename(fstab_entry->mount_point));
+    const std::string device_name(GetVerityDeviceName(*fstab_entry));
     android::dm::DeviceMapper& dm = android::dm::DeviceMapper::Instance();
-    if (!dm.CreateDevice(mount_point, table)) {
+    if (!dm.CreateDevice(device_name, table)) {
         LERROR << "Couldn't create verity device!";
         return false;
     }
 
     std::string dev_path;
-    if (!dm.GetDmDevicePathByName(mount_point, &dev_path)) {
+    if (!dm.GetDmDevicePathByName(device_name, &dev_path)) {
         LERROR << "Couldn't get verity device path!";
         return false;
     }