fanotify: groups can specify their f_flags for new fd

Currently fanotify fds opened for thier listeners are done with f_flags
equal to O_RDONLY | O_LARGEFILE.  This patch instead takes f_flags from the
fanotify_init syscall and uses those when opening files in the context of
the listener.

Signed-off-by: Eric Paris <eparis@redhat.com>

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index da01091..7182c83 100644 (file)
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -81,7 +81,7 @@ static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event)
         * are NULL;  That's fine, just don't call dentry open */
        if (dentry && mnt)
                new_file = dentry_open(dentry, mnt,
-                                      O_RDONLY | O_LARGEFILE | FMODE_NONOTIFY,
+                                      group->fanotify_data.f_flags | FMODE_NONOTIFY,
                                       current_cred());
        else
                new_file = ERR_PTR(-EOVERFLOW);
@@ -625,9 +625,6 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
        pr_debug("%s: flags=%d event_f_flags=%d\n",
                __func__, flags, event_f_flags);
 
-       if (event_f_flags)
-               return -EINVAL;
-
        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
 
@@ -645,6 +642,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
        if (IS_ERR(group))
                return PTR_ERR(group);
 
+       group->fanotify_data.f_flags = event_f_flags;
 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
        mutex_init(&group->fanotify_data.access_mutex);
        init_waitqueue_head(&group->fanotify_data.access_waitq);

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index a46355d..a83859d 100644 (file)
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -169,14 +169,17 @@ struct fsnotify_group {
                        struct user_struct      *user;
                } inotify_data;
 #endif
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+#ifdef CONFIG_FANOTIFY
                struct fanotify_group_private_data {
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
                        /* allows a group to block waiting for a userspace response */
                        struct mutex access_mutex;
                        struct list_head access_list;
                        wait_queue_head_t access_waitq;
+#endif /* CONFIG_FANOTIFY_ACCESS_PERMISSIONS */
+                       int f_flags;
                } fanotify_data;
-#endif
+#endif /* CONFIG_FANOTIFY */
        };
 };