3 files changed, 20 insertions, 3 deletions

diff --git a/fs/ecryptfs/kthread.c b/fs/ecryptfs/kthread.c
index 866bb18efefe..e818f5ac7a26 100644
--- a/fs/ecryptfs/kthread.c
+++ b/fs/ecryptfs/kthread.c
@@ -25,6 +25,7 @@
 #include <linux/slab.h>
 #include <linux/wait.h>
 #include <linux/mount.h>
+#include <linux/file.h>
 #include "ecryptfs_kernel.h"
 
 struct ecryptfs_open_req {
@@ -147,7 +148,7 @@ int ecryptfs_privileged_open(struct file **lower_file,
         flags |= IS_RDONLY(d_inode(lower_dentry)) ? O_RDONLY : O_RDWR;
         (*lower_file) = dentry_open(&req.path, flags, cred);
         if (!IS_ERR(*lower_file))
-                goto out;
+                goto have_file;
         if ((flags & O_ACCMODE) == O_RDONLY) {
                 rc = PTR_ERR((*lower_file));
                 goto out;
@@ -165,8 +166,16 @@ int ecryptfs_privileged_open(struct file **lower_file,
         mutex_unlock(&ecryptfs_kthread_ctl.mux);
         wake_up(&ecryptfs_kthread_ctl.wait);
         wait_for_completion(&req.done);
-        if (IS_ERR(*lower_file))
+        if (IS_ERR(*lower_file)) {
                 rc = PTR_ERR(*lower_file);
+                goto out;
+        }
+have_file:
+        if ((*lower_file)->f_op->mmap == NULL) {
+                fput(*lower_file);
+                *lower_file = NULL;
+                rc = -EMEDIUMTYPE;
+        }
 out:
         return rc;
 }
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 55bc7d6c8aac..06702783bf40 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -121,6 +121,13 @@ static struct dentry *proc_mount(struct file_system_type *fs_type,
         if (IS_ERR(sb))
                 return ERR_CAST(sb);
 
+        /*
+         * procfs isn't actually a stacking filesystem; however, there is
+         * too much magic going on inside it to permit stacking things on
+         * top of it
+         */
+        sb->s_stack_depth = FILESYSTEM_MAX_STACK_DEPTH;
+
         if (!proc_parse_options(options, ns)) {
                 deactivate_locked_super(sb);
                 return ERR_PTR(-EINVAL);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 385c947482e1..017d5394f5dc 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3170,7 +3170,8 @@ static noinline void __schedule_bug(struct task_struct *prev)
 static inline void schedule_debug(struct task_struct *prev)
 {
 #ifdef CONFIG_SCHED_STACK_END_CHECK
-        BUG_ON(task_stack_end_corrupted(prev));
+        if (task_stack_end_corrupted(prev))
+                panic("corrupted stack end detected inside scheduler\n");
 #endif
 
         if (unlikely(in_atomic_preempt_off())) {