Merge changes from topic "move_bionic_to_apex3" am: a15f385821 am: 90b7095cf5
am: 7ce93d2d0d
Change-Id: I670493883a18e604bb3cbc80979c76d0a725c0ef
diff --git a/adb/daemon/file_sync_service.cpp b/adb/daemon/file_sync_service.cpp
index 56b5cd8..9e1760d 100644
--- a/adb/daemon/file_sync_service.cpp
+++ b/adb/daemon/file_sync_service.cpp
@@ -25,6 +25,7 @@
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
@@ -209,6 +210,22 @@
return WriteFdExactly(s, &msg.dent, sizeof(msg.dent));
}
+static bool is_mountpoint(const std::string& path, pid_t tid) {
+ const std::string mountinfo_path = "/proc/" + std::to_string(tid) + "/mountinfo";
+ std::string mountinfo;
+ if (!android::base::ReadFileToString(mountinfo_path, &mountinfo)) {
+ PLOG(ERROR) << "Failed to open " << mountinfo_path;
+ return false;
+ }
+ std::vector<std::string> lines = android::base::Split(mountinfo, "\n");
+ return std::find_if(lines.begin(), lines.end(), [&path](const auto& line) {
+ auto tokens = android::base::Split(line, " ");
+ // line format is ...
+ // mountid parentmountid major:minor sourcepath targetpath option ...
+ return tokens.size() >= 4 && tokens[4] == path;
+ }) != lines.end();
+}
+
// Make sure that SendFail from adb_io.cpp isn't accidentally used in this file.
#pragma GCC poison SendFail
@@ -415,6 +432,18 @@
struct stat st;
bool do_unlink = (lstat(path.c_str(), &st) == -1) || S_ISREG(st.st_mode) ||
(S_ISLNK(st.st_mode) && !S_ISLNK(mode));
+
+ // If the path is a file that is a mount point, don't unlink it, but instead
+ // truncate to zero. If unlinked, existing mounts on the path is all
+ // unmounted
+ if (S_ISREG(st.st_mode) && is_mountpoint(path, getpid())) {
+ do_unlink = false;
+ if (truncate(path.c_str(), 0) == -1) {
+ SendSyncFail(s, "truncate to zero failed");
+ return false;
+ }
+ }
+
if (do_unlink) {
adb_unlink(path.c_str());
}
@@ -546,7 +575,64 @@
return true;
}
+#if defined(__ANDROID__)
+class FileSyncPreparer {
+ public:
+ FileSyncPreparer() : saved_ns_fd_(-1), rooted_(getuid() == 0) {
+ const std::string namespace_path = "/proc/" + std::to_string(gettid()) + "/ns/mnt";
+ const int ns_fd = adb_open(namespace_path.c_str(), O_RDONLY | O_CLOEXEC);
+ if (ns_fd == -1) {
+ if (rooted_) PLOG(ERROR) << "Failed to save mount namespace";
+ return;
+ }
+ saved_ns_fd_.reset(ns_fd);
+
+ // Note: this is for the current thread only
+ if (unshare(CLONE_NEWNS) != 0) {
+ if (rooted_) PLOG(ERROR) << "Failed to clone mount namespace";
+ return;
+ }
+
+ // Set the propagation type of / to private so that unmount below is
+ // not propagated to other mount namespaces.
+ if (mount(nullptr, "/", nullptr, MS_PRIVATE | MS_REC, nullptr) == -1) {
+ if (rooted_) PLOG(ERROR) << "Could not change propagation type of / to MS_PRIVATE";
+ return;
+ }
+
+ // unmount /bionic which is bind-mount to itself by init. Under /bionic,
+ // there are other bind mounts for the bionic files. By unmounting this,
+ // we unmount them all thus revealing the raw file system that is the
+ // same as the local file system seen by the adb client.
+ if (umount2("/bionic", MNT_DETACH) == -1 && errno != ENOENT) {
+ if (rooted_) PLOG(ERROR) << "Could not unmount /bionic to reveal raw filesystem";
+ return;
+ }
+ }
+
+ ~FileSyncPreparer() {
+ if (saved_ns_fd_.get() != -1) {
+ // In fact, this is not strictly required because this thread for file
+ // sync service will be destroyed after the current transfer is all
+ // done. However, let's restore the ns in case the same thread is
+ // reused by multiple transfers in the future refactoring.
+ if (setns(saved_ns_fd_, CLONE_NEWNS) == -1) {
+ PLOG(ERROR) << "Failed to restore saved mount namespace";
+ }
+ }
+ }
+
+ private:
+ unique_fd saved_ns_fd_;
+ bool rooted_;
+};
+#endif
+
void file_sync_service(unique_fd fd) {
+#if defined(__ANDROID__)
+ FileSyncPreparer preparer;
+#endif
+
std::vector<char> buffer(SYNC_DATA_MAX);
while (handle_sync_command(fd.get(), buffer)) {
diff --git a/adb/daemon/remount_service.cpp b/adb/daemon/remount_service.cpp
index b26c691..c36f1b6 100644
--- a/adb/daemon/remount_service.cpp
+++ b/adb/daemon/remount_service.cpp
@@ -230,6 +230,23 @@
android::base::SetProperty(ANDROID_RB_PROPERTY, reboot_cmd.c_str());
}
+static void try_unmount_bionic(int fd) {
+ static constexpr const char* kBionic = "/bionic";
+ struct statfs buf;
+ if (statfs(kBionic, &buf) == -1) {
+ WriteFdFmt(fd, "statfs of the %s mount failed: %s.\n", kBionic, strerror(errno));
+ return;
+ }
+ if (buf.f_flags & ST_RDONLY) {
+ // /bionic is on a read-only partition; can happen for
+ // non-system-as-root-devices. Don' try to unmount.
+ return;
+ }
+ // Success/Fail of the actual remount will be reported by the function.
+ remount_partition(fd, kBionic);
+ return;
+}
+
void remount_service(unique_fd fd, const std::string& cmd) {
bool user_requested_reboot = cmd == "-R";
@@ -323,6 +340,8 @@
return;
}
+ try_unmount_bionic(fd.get());
+
if (!success) {
WriteFdExactly(fd.get(), "remount failed\n");
} else {
diff --git a/fs_mgr/tests/adb-remount-test.sh b/fs_mgr/tests/adb-remount-test.sh
index ede0122..4d9bc61 100755
--- a/fs_mgr/tests/adb-remount-test.sh
+++ b/fs_mgr/tests/adb-remount-test.sh
@@ -569,6 +569,18 @@
die "vendor hello"
check_eq "${A}" "${B}" /vendor before reboot
+# download libc.so, append some gargage, push back, and check if the file is updated.
+tempdir="`mktemp -d`"
+cleanup() {
+ rm -rf ${tempdir}
+}
+adb pull /system/lib/bootstrap/libc.so ${tempdir} || die "pull libc.so from device"
+garbage="`hexdump -n 16 -e '4/4 "%08X" 1 "\n"' /dev/random`"
+echo ${garbage} >> ${tempdir}/libc.so
+adb push ${tempdir}/libc.so /system/lib/bootstrap/libc.so || die "push libc.so to device"
+adb pull /system/lib/bootstrap/libc.so ${tempdir}/libc.so.fromdevice || die "pull libc.so from device"
+diff ${tempdir}/libc.so ${tempdir}/libc.so.fromdevice > /dev/null || die "libc.so differ"
+
echo "${GREEN}[ RUN ]${NORMAL} reboot to confirm content persistent" >&2
adb_reboot &&
@@ -607,6 +619,14 @@
check_eq "${A}" "${B}" vendor after reboot
echo "${GREEN}[ OK ]${NORMAL} /vendor content remains after reboot" >&2
+# check if the updated libc.so is persistent after reboot
+adb_root &&
+ adb pull /system/lib/bootstrap/libc.so ${tempdir}/libc.so.fromdevice ||
+ die "pull libc.so from device"
+diff ${tempdir}/libc.so ${tempdir}/libc.so.fromdevice > /dev/null || die "libc.so differ"
+rm -r ${tempdir}
+echo "${GREEN}[ OK ]${NORMAL} /system/lib/bootstrap/libc.so content remains after reboot" >&2
+
echo "${GREEN}[ RUN ]${NORMAL} flash vendor, confirm its content disappears" >&2
H=`adb_sh echo '${HOSTNAME}' </dev/null 2>/dev/null`