1 files changed, 18 insertions, 33 deletions

diff --git a/fs/exec.c b/fs/exec.c
index 54a0a557b67..9f9f931ef94 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -735,6 +735,7 @@ static int exec_mmap(struct mm_struct *mm)
 	tsk->active_mm = mm;
 	activate_mm(active_mm, mm);
 	task_unlock(tsk);
+	mm_update_next_owner(mm);
 	arch_pick_mmap_layout(mm);
 	if (old_mm) {
 		up_read(&old_mm->mmap_sem);
@@ -765,9 +766,7 @@ static int de_thread(struct task_struct *tsk)
 
 	/*
 	 * Kill all other threads in the thread group.
-	 * We must hold tasklist_lock to call zap_other_threads.
 	 */
-	read_lock(&tasklist_lock);
 	spin_lock_irq(lock);
 	if (signal_group_exit(sig)) {
 		/*
@@ -775,21 +774,10 @@ static int de_thread(struct task_struct *tsk)
 		 * return so that the signal is processed.
 		 */
 		spin_unlock_irq(lock);
-		read_unlock(&tasklist_lock);
 		return -EAGAIN;
 	}
-
-	/*
-	 * child_reaper ignores SIGKILL, change it now.
-	 * Reparenting needs write_lock on tasklist_lock,
-	 * so it is safe to do it under read_lock.
-	 */
-	if (unlikely(tsk->group_leader == task_child_reaper(tsk)))
-		task_active_pid_ns(tsk)->child_reaper = tsk;
-
 	sig->group_exit_task = tsk;
 	zap_other_threads(tsk);
-	read_unlock(&tasklist_lock);
 
 	/* Account for the thread group leader hanging around: */
 	count = thread_group_leader(tsk) ? 1 : 2;
@@ -810,7 +798,7 @@ static int de_thread(struct task_struct *tsk)
 	if (!thread_group_leader(tsk)) {
 		leader = tsk->group_leader;
 
-		sig->notify_count = -1;
+		sig->notify_count = -1;	/* for exit_notify() */
 		for (;;) {
 			write_lock_irq(&tasklist_lock);
 			if (likely(leader->exit_state))
@@ -820,6 +808,8 @@ static int de_thread(struct task_struct *tsk)
 			schedule();
 		}
 
+		if (unlikely(task_child_reaper(tsk) == leader))
+			task_active_pid_ns(tsk)->child_reaper = tsk;
 		/*
 		 * The only record we have of the real-time age of a
 		 * process, regardless of execs it's done, is start_time.
@@ -953,7 +943,6 @@ int flush_old_exec(struct linux_binprm * bprm)
 {
 	char * name;
 	int i, ch, retval;
-	struct files_struct *files;
 	char tcomm[sizeof(current->comm)];
 
 	/*
@@ -964,27 +953,18 @@ int flush_old_exec(struct linux_binprm * bprm)
 	if (retval)
 		goto out;
 
-	/*
-	 * Make sure we have private file handles. Ask the
-	 * fork helper to do the work for us and the exit
-	 * helper to do the cleanup of the old one.
-	 */
-	files = current->files;		/* refcounted so safe to hold */
-	retval = unshare_files();
-	if (retval)
-		goto out;
+	set_mm_exe_file(bprm->mm, bprm->file);
+
 	/*
 	 * Release all of the old mmap stuff
 	 */
 	retval = exec_mmap(bprm->mm);
 	if (retval)
-		goto mmap_failed;
+		goto out;
 
 	bprm->mm = NULL;		/* We're using it now */
 
 	/* This is the point of no return */
-	put_files_struct(files);
-
 	current->sas_ss_sp = current->sas_ss_size = 0;
 
 	if (current->euid == current->uid && current->egid == current->gid)
@@ -1034,8 +1014,6 @@ int flush_old_exec(struct linux_binprm * bprm)
 
 	return 0;
 
-mmap_failed:
-	reset_files_struct(current, files);
 out:
 	return retval;
 }
@@ -1282,13 +1260,17 @@ int do_execve(char * filename,
 {
 	struct linux_binprm *bprm;
 	struct file *file;
-	unsigned long env_p;
+	struct files_struct *displaced;
 	int retval;
 
+	retval = unshare_files(&displaced);
+	if (retval)
+		goto out_ret;
+
 	retval = -ENOMEM;
 	bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
 	if (!bprm)
-		goto out_ret;
+		goto out_files;
 
 	file = open_exec(filename);
 	retval = PTR_ERR(file);
@@ -1330,11 +1312,9 @@ int do_execve(char * filename,
 	if (retval < 0)
 		goto out;
 
-	env_p = bprm->p;
 	retval = copy_strings(bprm->argc, argv, bprm);
 	if (retval < 0)
 		goto out;
-	bprm->argv_len = env_p - bprm->p;
 
 	retval = search_binary_handler(bprm,regs);
 	if (retval >= 0) {
@@ -1343,6 +1323,8 @@ int do_execve(char * filename,
 		security_bprm_free(bprm);
 		acct_update_integrals(current);
 		kfree(bprm);
+		if (displaced)
+			put_files_struct(displaced);
 		return retval;
 	}
 
@@ -1363,6 +1345,9 @@ out_file:
 out_kfree:
 	kfree(bprm);
 
+out_files:
+	if (displaced)
+		reset_files_struct(displaced);
 out_ret:
 	return retval;
 }