[PATCH] knfsd: nfsd4: clean up exp_pseudoroot

[powerpc.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index c9e660a..7dc6140 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1119,11 +1119,9 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                goto bad_fork_cleanup_mm;
        if ((retval = copy_namespaces(clone_flags, p)))
                goto bad_fork_cleanup_keys;
-       if ((retval = copy_namespace(clone_flags, p)))
-               goto bad_fork_cleanup_namespaces;
        retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs);
        if (retval)
-               goto bad_fork_cleanup_namespace;
+               goto bad_fork_cleanup_namespaces;
 
        p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
        /*
@@ -1215,7 +1213,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                spin_unlock(&current->sighand->siglock);
                write_unlock_irq(&tasklist_lock);
                retval = -ERESTARTNOINTR;
-               goto bad_fork_cleanup_namespace;
+               goto bad_fork_cleanup_namespaces;
        }
 
        if (clone_flags & CLONE_THREAD) {
@@ -1263,8 +1261,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
        proc_fork_connector(p);
        return p;
 
-bad_fork_cleanup_namespace:
-       exit_namespace(p);
 bad_fork_cleanup_namespaces:
        exit_task_namespaces(p);
 bad_fork_cleanup_keys:
@@ -1519,10 +1515,9 @@ static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp)
  */
 static int unshare_namespace(unsigned long unshare_flags, struct namespace **new_nsp, struct fs_struct *new_fs)
 {
-       struct namespace *ns = current->namespace;
+       struct namespace *ns = current->nsproxy->namespace;
 
-       if ((unshare_flags & CLONE_NEWNS) &&
-           (ns && atomic_read(&ns->count) > 1)) {
+       if ((unshare_flags & CLONE_NEWNS) && ns) {
                if (!capable(CAP_SYS_ADMIN))
                        return -EPERM;
 
@@ -1594,6 +1589,16 @@ static int unshare_semundo(unsigned long unshare_flags, struct sem_undo_list **n
        return 0;
 }
 
+#ifndef CONFIG_IPC_NS
+static inline int unshare_ipcs(unsigned long flags, struct ipc_namespace **ns)
+{
+       if (flags & CLONE_NEWIPC)
+               return -EINVAL;
+
+       return 0;
+}
+#endif
+
 /*
  * unshare allows a process to 'unshare' part of the process
  * context which was originally shared using clone.  copy_*
@@ -1611,14 +1616,17 @@ asmlinkage long sys_unshare(unsigned long unshare_flags)
        struct mm_struct *mm, *new_mm = NULL, *active_mm = NULL;
        struct files_struct *fd, *new_fd = NULL;
        struct sem_undo_list *new_ulist = NULL;
-       struct nsproxy *new_nsproxy, *old_nsproxy;
+       struct nsproxy *new_nsproxy = NULL, *old_nsproxy = NULL;
+       struct uts_namespace *uts, *new_uts = NULL;
+       struct ipc_namespace *ipc, *new_ipc = NULL;
 
        check_unshare_flags(&unshare_flags);
 
        /* Return -EINVAL for all unsupported flags */
        err = -EINVAL;
        if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND|
-                               CLONE_VM|CLONE_FILES|CLONE_SYSVSEM))
+                               CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|
+                               CLONE_NEWUTS|CLONE_NEWIPC))
                goto bad_unshare_out;
 
        if ((err = unshare_thread(unshare_flags)))
@@ -1635,18 +1643,29 @@ asmlinkage long sys_unshare(unsigned long unshare_flags)
                goto bad_unshare_cleanup_vm;
        if ((err = unshare_semundo(unshare_flags, &new_ulist)))
                goto bad_unshare_cleanup_fd;
+       if ((err = unshare_utsname(unshare_flags, &new_uts)))
+               goto bad_unshare_cleanup_semundo;
+       if ((err = unshare_ipcs(unshare_flags, &new_ipc)))
+               goto bad_unshare_cleanup_uts;
 
-       if (new_fs || new_ns || new_sigh || new_mm || new_fd || new_ulist) {
-
+       if (new_ns || new_uts || new_ipc) {
                old_nsproxy = current->nsproxy;
                new_nsproxy = dup_namespaces(old_nsproxy);
                if (!new_nsproxy) {
                        err = -ENOMEM;
-                       goto bad_unshare_cleanup_semundo;
+                       goto bad_unshare_cleanup_ipc;
                }
+       }
+
+       if (new_fs || new_ns || new_sigh || new_mm || new_fd || new_ulist ||
+                               new_uts || new_ipc) {
 
                task_lock(current);
-               current->nsproxy = new_nsproxy;
+
+               if (new_nsproxy) {
+                       current->nsproxy = new_nsproxy;
+                       new_nsproxy = old_nsproxy;
+               }
 
                if (new_fs) {
                        fs = current->fs;
@@ -1655,8 +1674,8 @@ asmlinkage long sys_unshare(unsigned long unshare_flags)
                }
 
                if (new_ns) {
-                       ns = current->namespace;
-                       current->namespace = new_ns;
+                       ns = current->nsproxy->namespace;
+                       current->nsproxy->namespace = new_ns;
                        new_ns = ns;
                }
 
@@ -1681,10 +1700,32 @@ asmlinkage long sys_unshare(unsigned long unshare_flags)
                        new_fd = fd;
                }
 
+               if (new_uts) {
+                       uts = current->nsproxy->uts_ns;
+                       current->nsproxy->uts_ns = new_uts;
+                       new_uts = uts;
+               }
+
+               if (new_ipc) {
+                       ipc = current->nsproxy->ipc_ns;
+                       current->nsproxy->ipc_ns = new_ipc;
+                       new_ipc = ipc;
+               }
+
                task_unlock(current);
-               put_nsproxy(old_nsproxy);
        }
 
+       if (new_nsproxy)
+               put_nsproxy(new_nsproxy);
+
+bad_unshare_cleanup_ipc:
+       if (new_ipc)
+               put_ipc_ns(new_ipc);
+
+bad_unshare_cleanup_uts:
+       if (new_uts)
+               put_uts_ns(new_uts);
+
 bad_unshare_cleanup_semundo:
 bad_unshare_cleanup_fd:
        if (new_fd)