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Commit 44b3c8c9 authored by Yi-Yo Chiang's avatar Yi-Yo Chiang Committed by Automerger Merge Worker
Browse files

Merge changes I2581fd7c,I1ed57e6d into main am: 64062f8f am: 112b3505 am:... 

Merge changes I2581fd7c,I1ed57e6d into main am: 64062f8f am: 112b3505 am: 0c813dbf am: 38f0f676

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2671040



Change-Id: I03214fe1f57a7af6c190c63988abf89d94be302e
Signed-off-by: default avatarAutomerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
parents 50fe91fa 38f0f676

fs_mgr/fs_mgr_fstab.cpp

+16 −10
Original line number Diff line number Diff line
@@ -328,8 +328,7 @@ bool ParseFsMgrFlags(const std::string& flags, FstabEntry* entry) { 
    // some recovery fstabs still contain the FDE options since they didn't do

    // anything in recovery mode anyway (except possibly to cause the

    // reservation of a crypto footer) and thus never got removed.

    if (entry->fs_mgr_flags.crypt && !entry->fs_mgr_flags.vold_managed &&

        access("/system/bin/recovery", F_OK) != 0) {

    if (entry->fs_mgr_flags.crypt && !entry->fs_mgr_flags.vold_managed && !InRecovery()) {

        LERROR << "FDE is no longer supported; 'encryptable' can only be used for adoptable "

                  "storage";

        return false;
@@ -520,6 +519,9 @@ std::vector<FstabPtrEntryType*> GetEntriesByPred(FstabPtr fstab, const Pred& pre 
// ramdisk's copy of the fstab had to be located in the root directory, but now

// the system/etc directory is supported too and is the preferred location.

std::string GetFstabPath() {

    if (InRecovery()) {

        return "/etc/recovery.fstab";

    }

    for (const char* prop : {"fstab_suffix", "hardware", "hardware.platform"}) {

        std::string suffix;
@@ -835,15 +837,8 @@ bool ReadDefaultFstab(Fstab* fstab) { 
    fstab->clear();

    ReadFstabFromDt(fstab, false /* verbose */);



    std::string default_fstab_path;

    // Use different fstab paths for normal boot and recovery boot, respectively

    if ((access("/sbin/recovery", F_OK) == 0) || (access("/system/bin/recovery", F_OK) == 0)) {

        default_fstab_path = "/etc/recovery.fstab";

    } else {  // normal boot

        default_fstab_path = GetFstabPath();

    }



    Fstab default_fstab;

    const std::string default_fstab_path = GetFstabPath();

    if (!default_fstab_path.empty() && ReadFstabFromFile(default_fstab_path, &default_fstab)) {

        for (auto&& entry : default_fstab) {

            fstab->emplace_back(std::move(entry));
@@ -936,6 +931,17 @@ std::string GetVerityDeviceName(const FstabEntry& entry) { 
    return base_device + "-verity";

}



bool InRecovery() {

    // Check the existence of recovery binary instead of using the compile time

    // __ANDROID_RECOVERY__ macro.

    // If BOARD_USES_RECOVERY_AS_BOOT is true, both normal and recovery boot

    // mode would use the same init binary, which would mean during normal boot

    // the '/init' binary is actually a symlink pointing to

    // init_second_stage.recovery, which would be compiled with

    // __ANDROID_RECOVERY__ defined.

    return access("/system/bin/recovery", F_OK) == 0 || access("/sbin/recovery", F_OK) == 0;

}



}  // namespace fs_mgr

}  // namespace android

fs_mgr/fs_mgr_overlayfs_control.cpp

+25 −130
Original line number Diff line number Diff line
@@ -18,17 +18,10 @@ 
#include <errno.h>

#include <fcntl.h>

#include <linux/fs.h>

#include <selinux/selinux.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/mount.h>

#include <sys/param.h>

#include <sys/stat.h>

#include <sys/statvfs.h>

#include <sys/types.h>

#include <sys/utsname.h>

#include <sys/vfs.h>

#include <unistd.h>



#include <algorithm>
@@ -38,13 +31,9 @@ 
#include <vector>



#include <android-base/file.h>

#include <android-base/macros.h>

#include <android-base/properties.h>

#include <android-base/strings.h>

#include <android-base/unique_fd.h>

#include <ext4_utils/ext4_utils.h>

#include <fs_mgr.h>

#include <fs_mgr/file_wait.h>

#include <fs_mgr_dm_linear.h>

#include <fs_mgr_overlayfs.h>

#include <fstab/fstab.h>
@@ -71,22 +60,25 @@ namespace { 


constexpr char kDataScratchSizeMbProp[] = "fs_mgr.overlayfs.data_scratch_size_mb";



constexpr char kPhysicalDevice[] = "/dev/block/by-name/";

constexpr char kScratchImageMetadata[] = "/metadata/gsi/remount/lp_metadata";



constexpr char kMkF2fs[] = "/system/bin/make_f2fs";

constexpr char kMkExt4[] = "/system/bin/mke2fs";



// Return true if everything is mounted, but before adb is started.  Right

// after 'trigger load_persist_props_action' is done.

static bool fs_mgr_boot_completed() {

    return android::base::GetBoolProperty("ro.persistent_properties.ready", false);

}



constexpr auto kPhysicalDevice = "/dev/block/by-name/";

constexpr char kScratchImageMetadata[] = "/metadata/gsi/remount/lp_metadata";



// Note: this is meant only for recovery/first-stage init.

static bool ScratchIsOnData() {

    // The scratch partition of DSU is managed by gsid.

    if (fs_mgr_is_dsu_running()) {

        return false;

    }

    return fs_mgr_access(kScratchImageMetadata);

    return access(kScratchImageMetadata, F_OK) == 0;

}



static bool fs_mgr_rm_all(const std::string& path, bool* change = nullptr, int level = 0) {
@@ -131,7 +123,7 @@ static bool fs_mgr_rm_all(const std::string& path, bool* change = nullptr, int l 
}



std::string fs_mgr_overlayfs_setup_dir(const std::string& dir) {

    auto top = dir + kOverlayTopDir;

    auto top = dir + "/" + kOverlayTopDir;



    AutoSetFsCreateCon createcon(kOverlayfsFileContext);

    if (!createcon.Ok()) {
@@ -195,10 +187,6 @@ static uint32_t fs_mgr_overlayfs_slot_number() { 
    return SlotNumberForSlotSuffix(fs_mgr_get_slot_suffix());

}



static std::string fs_mgr_overlayfs_super_device(uint32_t slot_number) {

    return kPhysicalDevice + fs_mgr_get_super_partition_name(slot_number);

}



static bool fs_mgr_overlayfs_has_logical(const Fstab& fstab) {

    for (const auto& entry : fstab) {

        if (entry.fs_mgr_flags.logical) {
@@ -258,8 +246,8 @@ OverlayfsTeardownResult fs_mgr_overlayfs_teardown_scratch(const std::string& ove 
    }



    auto slot_number = fs_mgr_overlayfs_slot_number();

    auto super_device = fs_mgr_overlayfs_super_device(slot_number);

    if (!fs_mgr_rw_access(super_device)) {

    const auto super_device = kPhysicalDevice + fs_mgr_get_super_partition_name();

    if (access(super_device.c_str(), R_OK | W_OK)) {

        return OverlayfsTeardownResult::Ok;

    }
@@ -290,9 +278,9 @@ OverlayfsTeardownResult fs_mgr_overlayfs_teardown_scratch(const std::string& ove 


bool fs_mgr_overlayfs_teardown_one(const std::string& overlay, const std::string& mount_point,

                                   bool* change, bool* should_destroy_scratch = nullptr) {

    const auto top = overlay + kOverlayTopDir;

    const auto top = overlay + "/" + kOverlayTopDir;



    if (!fs_mgr_access(top)) {

    if (access(top.c_str(), F_OK)) {

        if (should_destroy_scratch) *should_destroy_scratch = true;

        return true;

    }
@@ -300,7 +288,7 @@ bool fs_mgr_overlayfs_teardown_one(const std::string& overlay, const std::string 
    auto cleanup_all = mount_point.empty();

    const auto partition_name = android::base::Basename(mount_point);

    const auto oldpath = top + (cleanup_all ? "" : ("/" + partition_name));

    const auto newpath = cleanup_all ? overlay + "/." + (kOverlayTopDir + 1) + ".teardown"

    const auto newpath = cleanup_all ? overlay + "/." + kOverlayTopDir + ".teardown"

                                     : top + "/." + partition_name + ".teardown";

    auto ret = fs_mgr_rm_all(newpath);

    if (!rename(oldpath.c_str(), newpath.c_str())) {
@@ -346,72 +334,6 @@ bool fs_mgr_overlayfs_teardown_one(const std::string& overlay, const std::string 
    return ret;

}



// Mount kScratchMountPoint

bool MountScratch(const std::string& device_path, bool readonly = false) {

    if (readonly) {

        if (!fs_mgr_access(device_path)) {

            LOG(ERROR) << "Path does not exist: " << device_path;

            return false;

        }

    } else if (!fs_mgr_rw_access(device_path)) {

        LOG(ERROR) << "Path does not exist or is not readwrite: " << device_path;

        return false;

    }



    std::vector<const char*> filesystem_candidates;

    if (fs_mgr_is_f2fs(device_path)) {

        filesystem_candidates = {"f2fs", "ext4"};

    } else if (fs_mgr_is_ext4(device_path)) {

        filesystem_candidates = {"ext4", "f2fs"};

    } else {

        LOG(ERROR) << "Scratch partition is not f2fs or ext4";

        return false;

    }



    AutoSetFsCreateCon createcon(kOverlayfsFileContext);

    if (!createcon.Ok()) {

        return false;

    }

    if (mkdir(kScratchMountPoint, 0755) && (errno != EEXIST)) {

        PERROR << "create " << kScratchMountPoint;

        return false;

    }



    FstabEntry entry;

    entry.blk_device = device_path;

    entry.mount_point = kScratchMountPoint;

    entry.flags = MS_NOATIME | MS_RDONLY;

    if (!readonly) {

        entry.flags &= ~MS_RDONLY;

        entry.flags |= MS_SYNCHRONOUS;

        entry.fs_options = "nodiscard";

        fs_mgr_set_blk_ro(device_path, false);

    }

    // check_fs requires apex runtime library

    if (fs_mgr_overlayfs_already_mounted("/data", false)) {

        entry.fs_mgr_flags.check = true;

    }

    bool mounted = false;

    for (auto fs_type : filesystem_candidates) {

        entry.fs_type = fs_type;

        if (fs_mgr_do_mount_one(entry) == 0) {

            mounted = true;

            break;

        }

    }

    if (!createcon.Restore()) {

        return false;

    }

    if (!mounted) {

        rmdir(kScratchMountPoint);

        return false;

    }

    return true;

}



const std::string kMkF2fs("/system/bin/make_f2fs");

const std::string kMkExt4("/system/bin/mke2fs");



// Note: The scratch partition of DSU is managed by gsid, and should be initialized during

// first-stage-mount. Just check if the DM device for DSU scratch partition is created or not.

static std::string GetDsuScratchDevice() {
@@ -456,14 +378,14 @@ bool MakeScratchFilesystem(const std::string& scratch_device) { 
    // thus do not rely on fsck to correct problems that could creep in.

    auto fs_type = ""s;

    auto command = ""s;

    if (!access(kMkF2fs.c_str(), X_OK) && fs_mgr_filesystem_available("f2fs")) {

    if (!access(kMkF2fs, X_OK) && fs_mgr_filesystem_available("f2fs")) {

        fs_type = "f2fs";

        command = kMkF2fs + " -w ";

        command = kMkF2fs + " -w "s;

        command += std::to_string(getpagesize());

        command += " -f -d1 -l" + android::base::Basename(kScratchMountPoint);

    } else if (!access(kMkExt4.c_str(), X_OK) && fs_mgr_filesystem_available("ext4")) {

    } else if (!access(kMkExt4, X_OK) && fs_mgr_filesystem_available("ext4")) {

        fs_type = "ext4";

        command = kMkExt4 + " -F -b 4096 -t ext4 -m 0 -O has_journal -M " + kScratchMountPoint;

        command = kMkExt4 + " -F -b 4096 -t ext4 -m 0 -O has_journal -M "s + kScratchMountPoint;

    } else {

        LERROR << "No supported mkfs command or filesystem driver available, supported filesystems "

                  "are: f2fs, ext4";
@@ -506,7 +428,7 @@ static bool CreateDynamicScratch(std::string* scratch_device, bool* partition_ex 


    auto partition_create = !*partition_exists;

    auto slot_number = fs_mgr_overlayfs_slot_number();

    auto super_device = fs_mgr_overlayfs_super_device(slot_number);

    const auto super_device = kPhysicalDevice + fs_mgr_get_super_partition_name();

    auto builder = MetadataBuilder::New(super_device, slot_number);

    if (!builder) {

        LERROR << "open " << super_device << " metadata";
@@ -646,8 +568,8 @@ static bool CreateScratchOnData(std::string* scratch_device, bool* partition_exi 


static bool CanUseSuperPartition(const Fstab& fstab) {

    auto slot_number = fs_mgr_overlayfs_slot_number();

    auto super_device = fs_mgr_overlayfs_super_device(slot_number);

    if (!fs_mgr_rw_access(super_device) || !fs_mgr_overlayfs_has_logical(fstab)) {

    const auto super_device = kPhysicalDevice + fs_mgr_get_super_partition_name();

    if (access(super_device.c_str(), R_OK | W_OK) || !fs_mgr_overlayfs_has_logical(fstab)) {

        return false;

    }

    auto metadata = ReadMetadata(super_device, slot_number);
@@ -697,8 +619,8 @@ bool fs_mgr_overlayfs_setup_scratch(const Fstab& fstab) { 
    // If the partition exists, assume first that it can be mounted.

    if (partition_exists) {

        if (MountScratch(scratch_device)) {

            if (fs_mgr_access(std::string(kScratchMountPoint) + kOverlayTopDir) ||

                fs_mgr_filesystem_has_space(kScratchMountPoint)) {

            const auto top = kScratchMountPoint + "/"s + kOverlayTopDir;

            if (access(top.c_str(), F_OK) == 0 || fs_mgr_filesystem_has_space(kScratchMountPoint)) {

                return true;

            }

            // declare it useless, no overrides and no free space
@@ -717,32 +639,6 @@ bool fs_mgr_overlayfs_setup_scratch(const Fstab& fstab) { 
    return MountScratch(scratch_device);

}



// NOTE: OverlayfsSetupAllowed() must be "stricter" than OverlayfsTeardownAllowed().

// Setup is allowed only if teardown is also allowed.

bool OverlayfsSetupAllowed(bool verbose = false) {

    if (!kAllowOverlayfs) {

        if (verbose) {

            LOG(ERROR) << "Overlayfs remounts can only be used in debuggable builds";

        }

        return false;

    }

    // Check mandatory kernel patches.

    if (fs_mgr_overlayfs_valid() == OverlayfsValidResult::kNotSupported) {

        if (verbose) {

            LOG(ERROR) << "Kernel does not support overlayfs";

        }

        return false;

    }

    // in recovery or fastbootd, not allowed!

    if (fs_mgr_in_recovery()) {

        if (verbose) {

            LOG(ERROR) << "Unsupported overlayfs setup from recovery";

        }

        return false;

    }

    return true;

}



constexpr bool OverlayfsTeardownAllowed() {

    // Never allow on non-debuggable build.

    return kAllowOverlayfs;
@@ -844,7 +740,7 @@ static std::optional<MapInfo> EnsureScratchMapped() { 
    if (!info.device.empty()) {

        return {std::move(info)};

    }

    if (!fs_mgr_in_recovery()) {

    if (!InRecovery()) {

        return {};

    }
@@ -867,8 +763,7 @@ static std::optional<MapInfo> EnsureScratchMapped() { 
    }



    // Avoid uart spam by first checking for a scratch partition.

    auto metadata_slot = fs_mgr_overlayfs_slot_number();

    auto super_device = fs_mgr_overlayfs_super_device(metadata_slot);

    const auto super_device = kPhysicalDevice + fs_mgr_get_super_partition_name();

    auto metadata = ReadCurrentMetadata(super_device);

    if (!metadata) {

        return {};
@@ -1030,7 +925,7 @@ void TeardownAllOverlayForMountPoint(const std::string& mount_point) { 
    if (!OverlayfsTeardownAllowed()) {

        return;

    }

    if (!fs_mgr_in_recovery()) {

    if (!InRecovery()) {

        LERROR << __FUNCTION__ << "(): must be called within recovery.";

        return;

    }

fs_mgr/fs_mgr_overlayfs_control.h

+0 −2
Original line number Diff line number Diff line
@@ -14,8 +14,6 @@ 


#pragma once



#include <string>



#include <fstab/fstab.h>



// If "mount_point" is non-null, set up exactly one overlay.

fs_mgr/fs_mgr_overlayfs_mount.cpp

+21 −53
Original line number Diff line number Diff line
@@ -14,16 +14,12 @@ 
 * limitations under the License.

 */



#include <dirent.h>

#include <errno.h>

#include <fcntl.h>

#include <linux/fs.h>

#include <selinux/selinux.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/mount.h>

#include <sys/param.h>

#include <sys/stat.h>

#include <sys/statvfs.h>

#include <sys/types.h>
@@ -33,7 +29,6 @@ 


#include <algorithm>

#include <memory>

#include <optional>

#include <string>

#include <vector>
@@ -45,7 +40,6 @@ 
#include <ext4_utils/ext4_utils.h>

#include <fs_mgr.h>

#include <fs_mgr/file_wait.h>

#include <fs_mgr_dm_linear.h>

#include <fs_mgr_overlayfs.h>

#include <fstab/fstab.h>

#include <libdm/dm.h>
@@ -62,39 +56,21 @@ using namespace android::storage_literals; 


constexpr char kPreferCacheBackingStorageProp[] = "fs_mgr.overlayfs.prefer_cache_backing_storage";



bool fs_mgr_access(const std::string& path) {

    return access(path.c_str(), F_OK) == 0;

}



const auto kLowerdirOption = "lowerdir=";

const auto kUpperdirOption = "upperdir=";

constexpr char kCacheMountPoint[] = "/cache";

constexpr char kPhysicalDevice[] = "/dev/block/by-name/";



bool fs_mgr_in_recovery() {

    // Check the existence of recovery binary instead of using the compile time

    // __ANDROID_RECOVERY__ macro.

    // If BOARD_USES_RECOVERY_AS_BOOT is true, both normal and recovery boot

    // mode would use the same init binary, which would mean during normal boot

    // the '/init' binary is actually a symlink pointing to

    // init_second_stage.recovery, which would be compiled with

    // __ANDROID_RECOVERY__ defined.

    return fs_mgr_access("/system/bin/recovery");

}

constexpr char kLowerdirOption[] = "lowerdir=";

constexpr char kUpperdirOption[] = "upperdir=";



bool fs_mgr_is_dsu_running() {

    // Since android::gsi::CanBootIntoGsi() or android::gsi::MarkSystemAsGsi() is

    // never called in recovery, the return value of android::gsi::IsGsiRunning()

    // is not well-defined. In this case, just return false as being in recovery

    // implies not running a DSU system.

    if (fs_mgr_in_recovery()) return false;

    if (InRecovery()) return false;

    return android::gsi::IsGsiRunning();

}



const auto kCacheMountPoint = "/cache";



static bool IsABDevice() {

    return !android::base::GetProperty("ro.boot.slot_suffix", "").empty();

}



std::vector<const std::string> OverlayMountPoints() {

    // Never fallback to legacy cache mount point if within a DSU system,

    // because running a DSU system implies the device supports dynamic
@@ -105,7 +81,8 @@ std::vector<const std::string> OverlayMountPoints() { 


    // For non-A/B devices prefer cache backing storage if

    // kPreferCacheBackingStorageProp property set.

    if (!IsABDevice() && android::base::GetBoolProperty(kPreferCacheBackingStorageProp, false) &&

    if (fs_mgr_get_slot_suffix().empty() &&

        android::base::GetBoolProperty(kPreferCacheBackingStorageProp, false) &&

        android::base::GetIntProperty("ro.vendor.api_level", -1) < __ANDROID_API_T__) {

        return {kCacheMountPoint, kScratchMountPoint};

    }
@@ -118,11 +95,6 @@ static bool fs_mgr_is_dir(const std::string& path) { 
    return !stat(path.c_str(), &st) && S_ISDIR(st.st_mode);

}



bool fs_mgr_rw_access(const std::string& path) {

    if (path.empty()) return false;

    return access(path.c_str(), R_OK | W_OK) == 0;

}



// At less than 1% or 8MB of free space return value of false,

// means we will try to wrap with overlayfs.

bool fs_mgr_filesystem_has_space(const std::string& mount_point) {
@@ -141,13 +113,11 @@ bool fs_mgr_filesystem_has_space(const std::string& mount_point) { 
           (static_cast<uint64_t>(vst.f_bfree) * vst.f_frsize) >= kSizeThreshold;

}



const auto kPhysicalDevice = "/dev/block/by-name/";



static bool fs_mgr_update_blk_device(FstabEntry* entry) {

    if (entry->fs_mgr_flags.logical) {

        fs_mgr_update_logical_partition(entry);

    }

    if (fs_mgr_access(entry->blk_device)) {

    if (access(entry->blk_device.c_str(), F_OK) == 0) {

        return true;

    }

    if (entry->blk_device != "/dev/root") {
@@ -155,10 +125,10 @@ static bool fs_mgr_update_blk_device(FstabEntry* entry) { 
    }



    // special case for system-as-root (taimen and others)

    auto blk_device = std::string(kPhysicalDevice) + "system";

    if (!fs_mgr_access(blk_device)) {

    auto blk_device = kPhysicalDevice + "system"s;

    if (access(blk_device.c_str(), F_OK)) {

        blk_device += fs_mgr_get_slot_suffix();

        if (!fs_mgr_access(blk_device)) {

        if (access(blk_device.c_str(), F_OK)) {

            return false;

        }

    }
@@ -237,12 +207,12 @@ static std::string fs_mgr_get_overlayfs_candidate(const std::string& mount_point 
    if (!fs_mgr_is_dir(mount_point)) return "";

    const auto base = android::base::Basename(mount_point) + "/";

    for (const auto& overlay_mount_point : OverlayMountPoints()) {

        auto dir = overlay_mount_point + kOverlayTopDir + "/" + base;

        auto dir = overlay_mount_point + "/" + kOverlayTopDir + "/" + base;

        auto upper = dir + kUpperName;

        if (!fs_mgr_is_dir(upper)) continue;

        auto work = dir + kWorkName;

        if (!fs_mgr_is_dir(work)) continue;

        if (!fs_mgr_rw_access(work)) continue;

        if (access(work.c_str(), R_OK | W_OK)) continue;

        return dir;

    }

    return "";
@@ -527,13 +497,13 @@ static bool fs_mgr_overlayfs_mount(const FstabEntry& entry) { 
}



// Mount kScratchMountPoint

static bool MountScratch(const std::string& device_path, bool readonly = false) {

bool MountScratch(const std::string& device_path, bool readonly) {

    if (readonly) {

        if (!fs_mgr_access(device_path)) {

        if (access(device_path.c_str(), F_OK)) {

            LOG(ERROR) << "Path does not exist: " << device_path;

            return false;

        }

    } else if (!fs_mgr_rw_access(device_path)) {

    } else if (access(device_path.c_str(), R_OK | W_OK)) {

        LOG(ERROR) << "Path does not exist or is not readwrite: " << device_path;

        return false;

    }
@@ -589,9 +559,6 @@ static bool MountScratch(const std::string& device_path, bool readonly = false) 
    return true;

}



const std::string kMkF2fs("/system/bin/make_f2fs");

const std::string kMkExt4("/system/bin/mke2fs");



// Note: The scratch partition of DSU is managed by gsid, and should be initialized during

// first-stage-mount. Just check if the DM device for DSU scratch partition is created or not.

static std::string GetDsuScratchDevice() {
@@ -633,7 +600,7 @@ static std::string GetBootScratchDevice() { 


// NOTE: OverlayfsSetupAllowed() must be "stricter" than OverlayfsTeardownAllowed().

// Setup is allowed only if teardown is also allowed.

bool OverlayfsSetupAllowed(bool verbose = false) {

bool OverlayfsSetupAllowed(bool verbose) {

    if (!kAllowOverlayfs) {

        if (verbose) {

            LOG(ERROR) << "Overlayfs remounts can only be used in debuggable builds";
@@ -648,7 +615,7 @@ bool OverlayfsSetupAllowed(bool verbose = false) { 
        return false;

    }

    // in recovery or fastbootd, not allowed!

    if (fs_mgr_in_recovery()) {

    if (InRecovery()) {

        if (verbose) {

            LOG(ERROR) << "Unsupported overlayfs setup from recovery";

        }
@@ -728,7 +695,7 @@ static void TryMountScratch() { 
    // if verity is still disabled, i.e. no reboot occurred), and skips calling

    // fs_mgr_overlayfs_mount_all().

    auto scratch_device = GetBootScratchDevice();

    if (!fs_mgr_rw_access(scratch_device)) {

    if (access(scratch_device.c_str(), R_OK | W_OK)) {

        return;

    }

    if (!WaitForFile(scratch_device, 10s)) {
@@ -737,7 +704,8 @@ static void TryMountScratch() { 
    if (!MountScratch(scratch_device, true /* readonly */)) {

        return;

    }

    auto has_overlayfs_dir = fs_mgr_access(std::string(kScratchMountPoint) + kOverlayTopDir);

    const auto top = kScratchMountPoint + "/"s + kOverlayTopDir;

    const bool has_overlayfs_dir = access(top.c_str(), F_OK) == 0;

    fs_mgr_overlayfs_umount_scratch();

    if (has_overlayfs_dir) {

        MountScratch(scratch_device);

fs_mgr/fs_mgr_overlayfs_mount.h

+11 −13
Original line number Diff line number Diff line
@@ -20,9 +20,12 @@ 


#include <fstab/fstab.h>



bool fs_mgr_overlayfs_already_mounted(const std::string& mount_point, bool overlay_only = true);

bool fs_mgr_wants_overlayfs(android::fs_mgr::FstabEntry* entry);

android::fs_mgr::Fstab fs_mgr_overlayfs_candidate_list(const android::fs_mgr::Fstab& fstab);

constexpr char kOverlayfsFileContext[] = "u:object_r:overlayfs_file:s0";



constexpr char kScratchMountPoint[] = "/mnt/scratch";

constexpr char kOverlayTopDir[] = "overlay";

constexpr char kUpperName[] = "upper";

constexpr char kWorkName[] = "work";



#if ALLOW_ADBD_DISABLE_VERITY

constexpr bool kAllowOverlayfs = true;
@@ -45,18 +48,13 @@ class AutoSetFsCreateCon final { 
    bool restored_ = false;

};



constexpr auto kScratchMountPoint = "/mnt/scratch";

constexpr char kOverlayfsFileContext[] = "u:object_r:overlayfs_file:s0";



constexpr auto kUpperName = "upper";

constexpr auto kWorkName = "work";

constexpr auto kOverlayTopDir = "/overlay";



bool fs_mgr_is_dsu_running();

bool fs_mgr_in_recovery();

bool fs_mgr_access(const std::string& path);

bool fs_mgr_rw_access(const std::string& path);

bool fs_mgr_filesystem_has_space(const std::string& mount_point);

const std::string fs_mgr_mount_point(const std::string& mount_point);

bool OverlayfsSetupAllowed(bool verbose = false);

bool MountScratch(const std::string& device_path, bool readonly = false);

bool fs_mgr_overlayfs_umount_scratch();

std::vector<const std::string> OverlayMountPoints();

bool fs_mgr_overlayfs_already_mounted(const std::string& mount_point, bool overlay_only = true);

bool fs_mgr_wants_overlayfs(android::fs_mgr::FstabEntry* entry);

android::fs_mgr::Fstab fs_mgr_overlayfs_candidate_list(const android::fs_mgr::Fstab& fstab);