diff --git a/fs_mgr/libfiemap/image_manager.cpp b/fs_mgr/libfiemap/image_manager.cpp index c416f4df4..a5da6e342 100644 --- a/fs_mgr/libfiemap/image_manager.cpp +++ b/fs_mgr/libfiemap/image_manager.cpp @@ -531,11 +531,16 @@ bool ImageManager::MapImageDevice(const std::string& name, // If there is no intermediate device-mapper node, then partitions cannot be // opened writable due to sepolicy and exclusivity of having a mounted // filesystem. This should only happen on devices with no encryption, or - // devices with FBE and no metadata encryption. For these cases it suffices - // to perform normal file writes to /data/gsi (which is unencrypted). + // devices with FBE and no metadata encryption. For these cases we COULD + // perform normal writes to /data/gsi (which is unencrypted), but given that + // metadata encryption has been mandated since Android R, we don't actually + // support or test this. // - // Note: this is not gated on DeviceInfo, because the recovery-specific path - // must only be used in actual recovery. + // So, we validate here that /data is backed by device-mapper. This code + // isn't needed in recovery since there is no /data. + // + // If this logic sticks for a release, we can remove MapWithLoopDevice, as + // well as WrapUserdataIfNeeded in fs_mgr. std::string block_device; bool can_use_devicemapper; if (!FiemapWriter::GetBlockDeviceForFile(image_header, &block_device, &can_use_devicemapper)) { @@ -543,21 +548,16 @@ bool ImageManager::MapImageDevice(const std::string& name, return false; } - if (can_use_devicemapper) { - if (!MapWithDmLinear(*partition_opener_.get(), name, timeout_ms, path)) { - return false; - } - } else if (!MapWithLoopDevice(name, timeout_ms, path)) { - return false; - } -#else - // In recovery, we can *only* use device-mapper, since partitions aren't - // mounted. That also means we cannot call GetBlockDeviceForFile. - if (!MapWithDmLinear(*partition_opener_.get(), name, timeout_ms, path)) { + if (!can_use_devicemapper) { + LOG(ERROR) << "Cannot map image: /data must be mounted on top of device-mapper."; return false; } #endif + if (!MapWithDmLinear(*partition_opener_.get(), name, timeout_ms, path)) { + return false; + } + // Set a property so we remember this is mapped. auto prop_name = GetStatusPropertyName(name); if (!android::base::SetProperty(prop_name, *path)) {