2 files changed, 5 insertions, 35 deletions

diff --git a/chrome/browser/zygote_main_linux.cc b/chrome/browser/zygote_main_linux.cc
index 9b8ef98..08f730e 100644
--- a/chrome/browser/zygote_main_linux.cc
+++ b/chrome/browser/zygote_main_linux.cc
@@ -221,29 +221,15 @@ static bool MaybeEnterChroot() {
     }
 
     char reply;
-    std::vector<int> fds;
-    if (!base::RecvMsg(fd, &reply, 1, &fds)) {
+    if (HANDLE_EINTR(read(fd, &reply, 1)) != 1) {
       LOG(ERROR) << "Failed to read from chroot pipe: " << errno;
       return false;
     }
+
     if (reply != kChrootMeSuccess) {
       LOG(ERROR) << "Error code reply from chroot helper";
-      for (size_t i = 0; i < fds.size(); ++i)
-        HANDLE_EINTR(close(fds[i]));
-      return false;
-    }
-    if (fds.size() != 1) {
-      LOG(ERROR) << "Bad number of file descriptors from chroot helper";
-      for (size_t i = 0; i < fds.size(); ++i)
-        HANDLE_EINTR(close(fds[i]));
-      return false;
-    }
-    if (fchdir(fds[0]) == -1) {
-      LOG(ERROR) << "Failed to chdir to root directory: " << errno;
-      HANDLE_EINTR(close(fds[0]));
       return false;
     }
-    HANDLE_EINTR(close(fds[0]));
 
     static const int kMagicSandboxIPCDescriptor = 5;
     SkiaFontConfigUseIPCImplementation(kMagicSandboxIPCDescriptor);
diff --git a/sandbox/linux/suid/sandbox.cc b/sandbox/linux/suid/sandbox.cc
index abd066c..0119882 100644
--- a/sandbox/linux/suid/sandbox.cc
+++ b/sandbox/linux/suid/sandbox.cc
@@ -78,8 +78,7 @@ static int CloneChrootHelperProcess() {
     }
 
     rmdir(temp_dir);
-    fchown(chroot_dir_fd, 0, 0);
-    fchmod(chroot_dir_fd, 0555);
+    fchown(chroot_dir_fd, 0 /* root */, 0 /* root */);
 
     // We share our files structure with an untrusted process. As a security in
     // depth measure, we make sure that we can't open anything by mistake.
@@ -108,6 +107,7 @@ static int CloneChrootHelperProcess() {
 
     if (fchdir(chroot_dir_fd))
       FatalError("Cannot chdir into chroot temp directory");
+    fchmod(chroot_dir_fd, 0000 /* no-access */);
 
     struct stat st;
     if (stat(".", &st))
@@ -124,23 +124,7 @@ static int CloneChrootHelperProcess() {
 
     const char reply = kMsgChrootSuccessful;
     do {
-      struct msghdr msg = {0};
-      struct iovec iov = {(char *) &reply, 1};
-
-      msg.msg_iov = &iov;
-      msg.msg_iovlen = 1;
-
-      char control_buffer[CMSG_SPACE(sizeof(int))];
-      msg.msg_control = control_buffer;
-      msg.msg_controllen = sizeof(control_buffer);
-      struct cmsghdr* cmsg = CMSG_FIRSTHDR(&msg);
-      cmsg->cmsg_level = SOL_SOCKET;
-      cmsg->cmsg_type = SCM_RIGHTS;
-      cmsg->cmsg_len = CMSG_LEN(sizeof(int));
-      memcpy(CMSG_DATA(cmsg), &chroot_dir_fd, sizeof(int));
-      msg.msg_controllen = cmsg->cmsg_len;
-
-      bytes = sendmsg(sv[0], &msg, 0);
+      bytes = write(sv[0], &reply, 1);
     } while (bytes == -1 && errno == EINTR);
 
     if (bytes != 1)