diff options
Diffstat (limited to 'kernel/fork.c')
| -rw-r--r-- | kernel/fork.c | 69 |
1 files changed, 48 insertions, 21 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 115d6c2e4cc..c36c4e301ef 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1044,8 +1044,6 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) atomic_set(&sig->live, 1); atomic_set(&sig->sigcnt, 1); init_waitqueue_head(&sig->wait_chldexit); - if (clone_flags & CLONE_NEWPID) - sig->flags |= SIGNAL_UNKILLABLE; sig->curr_target = tsk; init_sigpending(&sig->shared_pending); INIT_LIST_HEAD(&sig->posix_timers); @@ -1438,8 +1436,10 @@ static struct task_struct *copy_process(unsigned long clone_flags, ptrace_init_task(p, (clone_flags & CLONE_PTRACE) || trace); if (thread_group_leader(p)) { - if (is_child_reaper(pid)) - p->nsproxy->pid_ns->child_reaper = p; + if (is_child_reaper(pid)) { + ns_of_pid(pid)->child_reaper = p; + p->signal->flags |= SIGNAL_UNKILLABLE; + } p->signal->leader_pid = pid; p->signal->tty = tty_kref_get(current->signal->tty); @@ -1473,8 +1473,6 @@ bad_fork_cleanup_io: if (p->io_context) exit_io_context(p); bad_fork_cleanup_namespaces: - if (unlikely(clone_flags & CLONE_NEWPID)) - pid_ns_release_proc(p->nsproxy->pid_ns); exit_task_namespaces(p); bad_fork_cleanup_mm: if (p->mm) @@ -1554,15 +1552,9 @@ long do_fork(unsigned long clone_flags, * Do some preliminary argument and permissions checking before we * actually start allocating stuff */ - if (clone_flags & CLONE_NEWUSER) { - if (clone_flags & CLONE_THREAD) + if (clone_flags & (CLONE_NEWUSER | CLONE_NEWPID)) { + if (clone_flags & (CLONE_THREAD|CLONE_PARENT)) return -EINVAL; - /* hopefully this check will go away when userns support is - * complete - */ - if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SETUID) || - !capable(CAP_SETGID)) - return -EPERM; } /* @@ -1724,7 +1716,8 @@ static int check_unshare_flags(unsigned long unshare_flags) { if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND| CLONE_VM|CLONE_FILES|CLONE_SYSVSEM| - CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET)) + CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET| + CLONE_NEWUSER|CLONE_NEWPID)) return -EINVAL; /* * Not implemented, but pretend it works if there is nothing to @@ -1791,19 +1784,40 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags) { struct fs_struct *fs, *new_fs = NULL; struct files_struct *fd, *new_fd = NULL; + struct cred *new_cred = NULL; struct nsproxy *new_nsproxy = NULL; int do_sysvsem = 0; int err; - err = check_unshare_flags(unshare_flags); - if (err) - goto bad_unshare_out; - + /* + * If unsharing a user namespace must also unshare the thread. + */ + if (unshare_flags & CLONE_NEWUSER) + unshare_flags |= CLONE_THREAD; + /* + * If unsharing a pid namespace must also unshare the thread. + */ + if (unshare_flags & CLONE_NEWPID) + unshare_flags |= CLONE_THREAD; + /* + * If unsharing a thread from a thread group, must also unshare vm. + */ + if (unshare_flags & CLONE_THREAD) + unshare_flags |= CLONE_VM; + /* + * If unsharing vm, must also unshare signal handlers. + */ + if (unshare_flags & CLONE_VM) + unshare_flags |= CLONE_SIGHAND; /* * If unsharing namespace, must also unshare filesystem information. */ if (unshare_flags & CLONE_NEWNS) unshare_flags |= CLONE_FS; + + err = check_unshare_flags(unshare_flags); + if (err) + goto bad_unshare_out; /* * CLONE_NEWIPC must also detach from the undolist: after switching * to a new ipc namespace, the semaphore arrays from the old @@ -1817,11 +1831,15 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags) err = unshare_fd(unshare_flags, &new_fd); if (err) goto bad_unshare_cleanup_fs; - err = unshare_nsproxy_namespaces(unshare_flags, &new_nsproxy, new_fs); + err = unshare_userns(unshare_flags, &new_cred); if (err) goto bad_unshare_cleanup_fd; + err = unshare_nsproxy_namespaces(unshare_flags, &new_nsproxy, + new_cred, new_fs); + if (err) + goto bad_unshare_cleanup_cred; - if (new_fs || new_fd || do_sysvsem || new_nsproxy) { + if (new_fs || new_fd || do_sysvsem || new_cred || new_nsproxy) { if (do_sysvsem) { /* * CLONE_SYSVSEM is equivalent to sys_exit(). @@ -1854,11 +1872,20 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags) } task_unlock(current); + + if (new_cred) { + /* Install the new user namespace */ + commit_creds(new_cred); + new_cred = NULL; + } } if (new_nsproxy) put_nsproxy(new_nsproxy); +bad_unshare_cleanup_cred: + if (new_cred) + put_cred(new_cred); bad_unshare_cleanup_fd: if (new_fd) put_files_struct(new_fd); |