1 files changed, 52 insertions, 7 deletions

diff --git a/fs/file_table.c b/fs/file_table.c
index c3dee381f1b..74a9544ac77 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -125,13 +125,13 @@ struct file *get_empty_filp(void)
                 goto fail;
 
         percpu_counter_inc(&nr_files);
+        f->f_cred = get_cred(cred);
         if (security_file_alloc(f))
                 goto fail_sec;
 
         INIT_LIST_HEAD(&f->f_u.fu_list);
         atomic_long_set(&f->f_count, 1);
         rwlock_init(&f->f_owner.lock);
-        f->f_cred = get_cred(cred);
         spin_lock_init(&f->f_lock);
         eventpoll_init_file(f);
         /* f->f_version: 0 */
@@ -276,11 +276,10 @@ struct file *fget(unsigned int fd)
         rcu_read_lock();
         file = fcheck_files(files, fd);
         if (file) {
-                if (!atomic_long_inc_not_zero(&file->f_count)) {
-                        /* File object ref couldn't be taken */
-                        rcu_read_unlock();
-                        return NULL;
-                }
+                /* File object ref couldn't be taken */
+                if (file->f_mode & FMODE_PATH ||
+                    !atomic_long_inc_not_zero(&file->f_count))
+                        file = NULL;
         }
         rcu_read_unlock();
 
@@ -289,6 +288,25 @@ struct file *fget(unsigned int fd)
 
 EXPORT_SYMBOL(fget);
 
+struct file *fget_raw(unsigned int fd)
+{
+        struct file *file;
+        struct files_struct *files = current->files;
+
+        rcu_read_lock();
+        file = fcheck_files(files, fd);
+        if (file) {
+                /* File object ref couldn't be taken */
+                if (!atomic_long_inc_not_zero(&file->f_count))
+                        file = NULL;
+        }
+        rcu_read_unlock();
+
+        return file;
+}
+
+EXPORT_SYMBOL(fget_raw);
+
 /*
  * Lightweight file lookup - no refcnt increment if fd table isn't shared.
  *
@@ -311,7 +329,34 @@ struct file *fget_light(unsigned int fd, int *fput_needed)
         struct files_struct *files = current->files;
 
         *fput_needed = 0;
-        if (likely((atomic_read(&files->count) == 1))) {
+        if (atomic_read(&files->count) == 1) {
+                file = fcheck_files(files, fd);
+                if (file && (file->f_mode & FMODE_PATH))
+                        file = NULL;
+        } else {
+                rcu_read_lock();
+                file = fcheck_files(files, fd);
+                if (file) {
+                        if (!(file->f_mode & FMODE_PATH) &&
+                            atomic_long_inc_not_zero(&file->f_count))
+                                *fput_needed = 1;
+                        else
+                                /* Didn't get the reference, someone's freed */
+                                file = NULL;
+                }
+                rcu_read_unlock();
+        }
+
+        return file;
+}
+
+struct file *fget_raw_light(unsigned int fd, int *fput_needed)
+{
+        struct file *file;
+        struct files_struct *files = current->files;
+
+        *fput_needed = 0;
+        if (atomic_read(&files->count) == 1) {
                 file = fcheck_files(files, fd);
         } else {
                 rcu_read_lock();