vold: Refactor Processkiller and add command to return users of a mount point
Signed-off-by: San Mehat <[email protected]>
diff --git a/Process.cpp b/Process.cpp
new file mode 100644
index 0000000..c3c9904
--- /dev/null
+++ b/Process.cpp
@@ -0,0 +1,221 @@
+/*
+ * 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 <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <ctype.h>
+#include <pwd.h>
+#include <stdlib.h>
+#include <poll.h>
+#include <sys/stat.h>
+#include <signal.h>
+
+#define LOG_TAG "ProcessKiller"
+#include <cutils/log.h>
+
+#include "Process.h"
+
+int Process::readSymLink(const char *path, char *link, size_t max) {
+ struct stat s;
+ int length;
+
+ if (lstat(path, &s) < 0)
+ return 0;
+ if ((s.st_mode & S_IFMT) != S_IFLNK)
+ return 0;
+
+ // we have a symlink
+ length = readlink(path, link, max- 1);
+ if (length <= 0)
+ return 0;
+ link[length] = 0;
+ return 1;
+}
+
+int Process::pathMatchesMountPoint(const char* path, const char* mountPoint) {
+ int length = strlen(mountPoint);
+ if (length > 1 && strncmp(path, mountPoint, length) == 0) {
+ // we need to do extra checking if mountPoint does not end in a '/'
+ if (mountPoint[length - 1] == '/')
+ return 1;
+ // if mountPoint does not have a trailing slash, we need to make sure
+ // there is one in the path to avoid partial matches.
+ return (path[length] == 0 || path[length] == '/');
+ }
+
+ return 0;
+}
+
+void Process::getProcessName(int pid, char *buffer, size_t max) {
+ int fd;
+ snprintf(buffer, max, "/proc/%d/cmdline", pid);
+ fd = open(buffer, O_RDONLY);
+ if (fd < 0) {
+ strcpy(buffer, "???");
+ } else {
+ int length = read(fd, buffer, max - 1);
+ buffer[length] = 0;
+ close(fd);
+ }
+}
+
+int Process::checkFileDescriptorSymLinks(int pid, const char *mountPoint) {
+ return checkFileDescriptorSymLinks(pid, mountPoint, NULL, 0);
+}
+
+int Process::checkFileDescriptorSymLinks(int pid, const char *mountPoint, char *openFilename, size_t max) {
+
+
+ // compute path to process's directory of open files
+ char path[PATH_MAX];
+ sprintf(path, "/proc/%d/fd", pid);
+ DIR *dir = opendir(path);
+ if (!dir)
+ return 0;
+
+ // remember length of the path
+ int parent_length = strlen(path);
+ // append a trailing '/'
+ path[parent_length++] = '/';
+
+ struct dirent* de;
+ while ((de = readdir(dir))) {
+ if (!strcmp(de->d_name, ".") || !strcmp(de->d_name, ".."))
+ continue;
+
+ // append the file name, after truncating to parent directory
+ path[parent_length] = 0;
+ strcat(path, de->d_name);
+
+ char link[PATH_MAX];
+
+ if (readSymLink(path, link, sizeof(link)) && pathMatchesMountPoint(link, mountPoint)) {
+ if (openFilename) {
+ memset(openFilename, 0, max);
+ strncpy(openFilename, link, max-1);
+ }
+ closedir(dir);
+ return 1;
+ }
+ }
+
+ closedir(dir);
+ return 0;
+}
+
+int Process::checkFileMaps(int pid, const char *mountPoint) {
+ return checkFileMaps(pid, mountPoint, NULL, 0);
+}
+
+int Process::checkFileMaps(int pid, const char *mountPoint, char *openFilename, size_t max) {
+ FILE *file;
+ char buffer[PATH_MAX + 100];
+
+ sprintf(buffer, "/proc/%d/maps", pid);
+ file = fopen(buffer, "r");
+ if (!file)
+ return 0;
+
+ while (fgets(buffer, sizeof(buffer), file)) {
+ // skip to the path
+ const char* path = strchr(buffer, '/');
+ if (path && pathMatchesMountPoint(path, mountPoint)) {
+ if (openFilename) {
+ memset(openFilename, 0, max);
+ strncpy(openFilename, path, max-1);
+ }
+ fclose(file);
+ return 1;
+ }
+ }
+
+ fclose(file);
+ return 0;
+}
+
+int Process::checkSymLink(int pid, const char *mountPoint, const char *name) {
+ char path[PATH_MAX];
+ char link[PATH_MAX];
+
+ sprintf(path, "/proc/%d/%s", pid, name);
+ if (readSymLink(path, link, sizeof(link)) && pathMatchesMountPoint(link, mountPoint))
+ return 1;
+ return 0;
+}
+
+int Process::getPid(const char *s) {
+ int result = 0;
+ while (*s) {
+ if (!isdigit(*s)) return -1;
+ result = 10 * result + (*s++ - '0');
+ }
+ return result;
+}
+
+/*
+ * Hunt down processes that have files open at the given mount point.
+ * action = 0 to just warn,
+ * action = 1 to SIGHUP,
+ * action = 2 to SIGKILL
+ */
+// hunt down and kill processes that have files open on the given mount point
+void Process::killProcessesWithOpenFiles(const char *path, int action) {
+ DIR* dir;
+ struct dirent* de;
+
+ if (!(dir = opendir("/proc"))) {
+ LOGE("opendir failed (%s)", strerror(errno));
+ return;
+ }
+
+ while ((de = readdir(dir))) {
+ int killed = 0;
+ int pid = getPid(de->d_name);
+ char name[PATH_MAX];
+
+ if (pid == -1)
+ continue;
+ getProcessName(pid, name, sizeof(name));
+
+ char openfile[PATH_MAX];
+
+ if (checkFileDescriptorSymLinks(pid, path, openfile, sizeof(openfile))) {
+ LOGE("Process %s (%d) has open file %s", name, pid, openfile);
+ } else if (checkFileMaps(pid, path, openfile, sizeof(openfile))) {
+ LOGE("Process %s (%d) has open filemap for %s", name, pid, openfile);
+ } else if (checkSymLink(pid, path, "cwd")) {
+ LOGE("Process %s (%d) has cwd within %s", name, pid, path);
+ } else if (checkSymLink(pid, path, "root")) {
+ LOGE("Process %s (%d) has chroot within %s", name, pid, path);
+ } else if (checkSymLink(pid, path, "exe")) {
+ LOGE("Process %s (%d) has executable path within %s", name, pid, path);
+ } else {
+ continue;
+ }
+ if (action == 1) {
+ LOGW("Sending SIGHUP to process %d", pid);
+ kill(pid, SIGTERM);
+ } else if (action == 2) {
+ LOGE("Sending SIGKILL to process %d", pid);
+ kill(pid, SIGKILL);
+ }
+ }
+ closedir(dir);
+}
