From: Serge E. Hallyn <serue@xxxxxxxxxx>
Add -t as an nsexec option to request new devpts.
Automatically remount /proc if we are starting a new pidns.
Signed-off-by: Serge E. Hallyn <serue@xxxxxxxxxx>
---
nsexec.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++--
1 files changed, 48 insertions(+), 2 deletions(-)
diff --git a/nsexec.c b/nsexec.c
index 8b96bc9..3a825f1 100644
--- a/nsexec.c
+++ b/nsexec.c
@@ -15,6 +15,7 @@
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
+#include <sys/mount.h>
#include "clone.h"
#include "eclone.h"
@@ -43,6 +44,7 @@ static void usage(const char *name)
printf(" -i ipc namespace\n");
printf(" -P <pid-file> File in which to write global pid of cinit\n");
printf(" -p pid namespace\n");
+ printf(" -t mount new devpts\n");
printf(" -f <flag> extra clone flags\n");
printf("\n");
printf("(C) Copyright IBM Corp. 2006\n");
@@ -189,6 +191,38 @@ int do_child(void *vargv)
if (check_newcgrp())
return 1;
+ /* if pid == 1 then remount /proc */
+ /* But if the container has no /proc don't fret */
+ if (getpid() == 1) {
+ umount2("/proc", MNT_DETACH);
+ mount("proc", "/proc", "proc", 0, NULL);
+ }
+
+ /* check if we should remount devpts */
+ if (strcmp(argv[0], "newpts") == 0) {
+ struct stat ptystat;
+ argv++;
+ if (lstat("/dev/ptmx", &ptystat) < 0) {
+ perror("stat /dev/ptmx");
+ return -1;
+ }
+ if ((ptystat.st_mode & S_IFMT) != S_IFLNK) {
+ printf("Error: /dev/ptmx must be a link to /dev/pts/ptmx\n");
+ printf(" do: chmod 666 /dev/pts/ptmx\n");
+ printf(" rm /dev/ptmx\n");
+ printf(" ln -s /dev/pts/ptmx /dev/ptmx\n");
+ return -1;
+ }
+
+ /* if container had no /dev/pts mounted don't fret */
+ umount2("/dev/pts", MNT_DETACH);
+
+ if (mount("pts", "/dev/pts", "devpts", 0, "ptmxmode=666,newinstance") < 0) {
+ perror("mount -t devpts -o newinstance");
+ return -1;
+ }
+ }
+
execve(argv[0], argv, __environ);
perror("execve");
return 1;
@@ -217,18 +251,19 @@ int main(int argc, char *argv[])
unsigned long flags = 0, eflags = 0;
char ttyname[256];
int status;
- int ret, use_clone = 0;
+ int ret, use_clone = 0, newpts = 0;
int pid;
char *pid_file = NULL;
size_t nr_pids = 1;
pid_t chosen_pid = 0;
+ char **newargv;
procname = basename(argv[0]);
memset(ttyname, '\0', sizeof(ttyname));
readlink("/proc/self/fd/0", ttyname, sizeof(ttyname));
- while ((c = getopt(argc, argv, "+mguUiphz:cnf:P:")) != EOF) {
+ while ((c = getopt(argc, argv, "+mguUiphz:cntf:P:")) != EOF) {
switch (c) {
case 'g': do_newcgrp = getpid(); break;
case 'm': flags |= CLONE_NEWNS; break;
@@ -239,6 +274,7 @@ int main(int argc, char *argv[])
case 'U': flags |= CLONE_NEWUSER; break;
case 'n': flags |= CLONE_NEWNET; break;
case 'p': flags |= CLONE_NEWNS|CLONE_NEWPID; break;
+ case 't': newpts = 1; flags |= CLONE_NEWNS; break;
case 'z': chosen_pid = atoi(optarg); break;
case 'f': if (!string_to_ul(optarg, &eflags)) {
flags |= eflags;
@@ -259,6 +295,16 @@ int main(int argc, char *argv[])
}
argv = &argv[optind];
argc = argc - optind;
+ if (newpts) {
+ /* tell do_child about newpts through first arg */
+ int i;
+ newargv = (char **) malloc(sizeof(char *) * (argc+2));
+ newargv[0] = "newpts";
+ newargv[argc+1] = NULL;
+ for (i=0; i<argc; i++)
+ newargv[i+1] = argv[i];
+ argv = newargv;
+ }
if (do_newcgrp) {
ret = pipe(pipefd);
--
1.6.0.6
_______________________________________________
Containers mailing list
Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linux-foundation.org/mailman/listinfo/containers
