blob: c1d55eedcc58d88bdac1dd50d11add488054f56f [file] [log] [blame]
/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <fts.h>
#include <poll.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fstream>
#include <mntent.h>
#include <unordered_set>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/parseint.h>
#include <android-base/stringprintf.h>
#include <android-base/strings.h>
#include "Process.h"
#include "Utils.h"
using android::base::StringPrintf;
namespace android {
namespace vold {
static bool checkMaps(const std::string& path, const std::string& prefix) {
bool found = false;
auto file = std::unique_ptr<FILE, decltype(&fclose)>{fopen(path.c_str(), "re"), fclose};
if (!file) {
return false;
}
char* buf = nullptr;
size_t len = 0;
while (getline(&buf, &len, file.get()) != -1) {
std::string line(buf);
std::string::size_type pos = line.find('/');
if (pos != std::string::npos) {
line = line.substr(pos);
if (android::base::StartsWith(line, prefix)) {
LOG(WARNING) << "Found map " << path << " referencing " << line;
found = true;
break;
}
}
}
free(buf);
return found;
}
static bool checkSymlink(const std::string& path, const std::string& prefix) {
std::string res;
if (android::base::Readlink(path, &res)) {
if (android::base::StartsWith(res, prefix)) {
LOG(WARNING) << "Found symlink " << path << " referencing " << res;
return true;
}
}
return false;
}
// TODO: Refactor the code with KillProcessesWithOpenFiles().
int KillProcessesWithTmpfsMounts(const std::string& prefix, int signal) {
std::unordered_set<pid_t> pids;
auto proc_d = std::unique_ptr<DIR, int (*)(DIR*)>(opendir("/proc"), closedir);
if (!proc_d) {
PLOG(ERROR) << "Failed to open proc";
return -1;
}
struct dirent* proc_de;
while ((proc_de = readdir(proc_d.get())) != nullptr) {
// We only care about valid PIDs
pid_t pid;
if (proc_de->d_type != DT_DIR) continue;
if (!android::base::ParseInt(proc_de->d_name, &pid)) continue;
// Look for references to prefix
std::string mounts_file(StringPrintf("/proc/%d/mounts", pid));
auto fp = std::unique_ptr<FILE, int (*)(FILE*)>(
setmntent(mounts_file.c_str(), "r"), endmntent);
if (!fp) {
PLOG(WARNING) << "Failed to open " << mounts_file;
continue;
}
// Check if obb directory is mounted, and get all packages of mounted app data directory.
mntent* mentry;
while ((mentry = getmntent(fp.get())) != nullptr) {
if (mentry->mnt_fsname != nullptr && strncmp(mentry->mnt_fsname, "tmpfs", 5) == 0
&& android::base::StartsWith(mentry->mnt_dir, prefix)) {
pids.insert(pid);
break;
}
}
}
if (signal != 0) {
for (const auto& pid : pids) {
LOG(WARNING) << "Killing pid "<< pid << " with signal " << strsignal(signal) <<
" because it has a mount with prefix " << prefix;
kill(pid, signal);
}
}
return pids.size();
}
int KillProcessesWithOpenFiles(const std::string& prefix, int signal, bool killFuseDaemon) {
std::unordered_set<pid_t> pids;
auto proc_d = std::unique_ptr<DIR, int (*)(DIR*)>(opendir("/proc"), closedir);
if (!proc_d) {
PLOG(ERROR) << "Failed to open proc";
return -1;
}
struct dirent* proc_de;
while ((proc_de = readdir(proc_d.get())) != nullptr) {
// We only care about valid PIDs
pid_t pid;
if (proc_de->d_type != DT_DIR) continue;
if (!android::base::ParseInt(proc_de->d_name, &pid)) continue;
// Look for references to prefix
bool found = false;
auto path = StringPrintf("/proc/%d", pid);
found |= checkMaps(path + "/maps", prefix);
found |= checkSymlink(path + "/cwd", prefix);
found |= checkSymlink(path + "/root", prefix);
found |= checkSymlink(path + "/exe", prefix);
auto fd_path = path + "/fd";
auto fd_d = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(fd_path.c_str()), closedir);
if (!fd_d) {
PLOG(WARNING) << "Failed to open " << fd_path;
} else {
struct dirent* fd_de;
while ((fd_de = readdir(fd_d.get())) != nullptr) {
if (fd_de->d_type != DT_LNK) continue;
found |= checkSymlink(fd_path + "/" + fd_de->d_name, prefix);
}
}
if (found) {
if (!IsFuseDaemon(pid) || killFuseDaemon) {
pids.insert(pid);
} else {
LOG(WARNING) << "Found FUSE daemon with open file. Skipping...";
}
}
}
if (signal != 0) {
for (const auto& pid : pids) {
std::string comm;
android::base::ReadFileToString(StringPrintf("/proc/%d/comm", pid), &comm);
comm = android::base::Trim(comm);
std::string exe;
android::base::Readlink(StringPrintf("/proc/%d/exe", pid), &exe);
LOG(WARNING) << "Sending " << strsignal(signal) << " to pid " << pid << " (" << comm
<< ", " << exe << ")";
kill(pid, signal);
}
}
return pids.size();
}
} // namespace vold
} // namespace android