fanotify: clean up CONFIG_FANOTIFY_ACCESS_PERMISSIONS ifdefs
authorMiklos Szeredi <mszeredi@redhat.com>
Mon, 30 Oct 2017 20:14:56 +0000 (21:14 +0100)
committerJan Kara <jack@suse.cz>
Tue, 31 Oct 2017 16:54:56 +0000 (17:54 +0100)
The only negative from this patch should be an addition of 32bytes to
'struct fsnotify_group' if CONFIG_FANOTIFY_ACCESS_PERMISSIONS is not
defined.

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
fs/notify/fanotify/fanotify.c
fs/notify/fanotify/fanotify.h
fs/notify/fanotify/fanotify_user.c
include/linux/fsnotify_backend.h

index df3f484e458aa3e516657eca6e44ebe553d3e077..63f56b00728060b964c3b30e02af3fa04e179a83 100644 (file)
@@ -35,15 +35,13 @@ static int fanotify_merge(struct list_head *list, struct fsnotify_event *event)
 
        pr_debug("%s: list=%p event=%p\n", __func__, list, event);
 
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
        /*
         * Don't merge a permission event with any other event so that we know
         * the event structure we have created in fanotify_handle_event() is the
         * one we should check for permission response.
         */
-       if (event->mask & FAN_ALL_PERM_EVENTS)
+       if (fanotify_is_perm_event(event->mask))
                return 0;
-#endif
 
        list_for_each_entry_reverse(test_event, list, list) {
                if (should_merge(test_event, event)) {
@@ -55,7 +53,6 @@ static int fanotify_merge(struct list_head *list, struct fsnotify_event *event)
        return 0;
 }
 
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
 static int fanotify_get_response(struct fsnotify_group *group,
                                 struct fanotify_perm_event_info *event,
                                 struct fsnotify_iter_info *iter_info)
@@ -82,7 +79,6 @@ static int fanotify_get_response(struct fsnotify_group *group,
        
        return ret;
 }
-#endif
 
 static bool fanotify_should_send_event(struct fsnotify_mark *inode_mark,
                                       struct fsnotify_mark *vfsmnt_mark,
@@ -141,8 +137,7 @@ struct fanotify_event_info *fanotify_alloc_event(struct inode *inode, u32 mask,
 {
        struct fanotify_event_info *event;
 
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       if (mask & FAN_ALL_PERM_EVENTS) {
+       if (fanotify_is_perm_event(mask)) {
                struct fanotify_perm_event_info *pevent;
 
                pevent = kmem_cache_alloc(fanotify_perm_event_cachep,
@@ -153,7 +148,6 @@ struct fanotify_event_info *fanotify_alloc_event(struct inode *inode, u32 mask,
                pevent->response = 0;
                goto init;
        }
-#endif
        event = kmem_cache_alloc(fanotify_event_cachep, GFP_KERNEL);
        if (!event)
                return NULL;
@@ -200,8 +194,7 @@ static int fanotify_handle_event(struct fsnotify_group *group,
        pr_debug("%s: group=%p inode=%p mask=%x\n", __func__, group, inode,
                 mask);
 
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       if (mask & FAN_ALL_PERM_EVENTS) {
+       if (fanotify_is_perm_event(mask)) {
                /*
                 * fsnotify_prepare_user_wait() fails if we race with mark
                 * deletion.  Just let the operation pass in that case.
@@ -209,7 +202,6 @@ static int fanotify_handle_event(struct fsnotify_group *group,
                if (!fsnotify_prepare_user_wait(iter_info))
                        return 0;
        }
-#endif
 
        event = fanotify_alloc_event(inode, mask, data);
        ret = -ENOMEM;
@@ -225,21 +217,15 @@ static int fanotify_handle_event(struct fsnotify_group *group,
                fsnotify_destroy_event(group, fsn_event);
 
                ret = 0;
-               goto finish;
-       }
-
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       if (mask & FAN_ALL_PERM_EVENTS) {
+       } else if (fanotify_is_perm_event(mask)) {
                ret = fanotify_get_response(group, FANOTIFY_PE(fsn_event),
                                            iter_info);
                fsnotify_destroy_event(group, fsn_event);
        }
 finish:
-       if (mask & FAN_ALL_PERM_EVENTS)
+       if (fanotify_is_perm_event(mask))
                fsnotify_finish_user_wait(iter_info);
-#else
-finish:
-#endif
+
        return ret;
 }
 
@@ -259,13 +245,11 @@ static void fanotify_free_event(struct fsnotify_event *fsn_event)
        event = FANOTIFY_E(fsn_event);
        path_put(&event->path);
        put_pid(event->tgid);
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       if (fsn_event->mask & FAN_ALL_PERM_EVENTS) {
+       if (fanotify_is_perm_event(fsn_event->mask)) {
                kmem_cache_free(fanotify_perm_event_cachep,
                                FANOTIFY_PE(fsn_event));
                return;
        }
-#endif
        kmem_cache_free(fanotify_event_cachep, event);
 }
 
index 4eb6f5efa282527f4d2d4824fcf80267f0b68be7..dc219cf07a6a51bac0e4f64419c35ffe588cfda6 100644 (file)
@@ -21,7 +21,6 @@ struct fanotify_event_info {
        struct pid *tgid;
 };
 
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
 /*
  * Structure for permission fanotify events. It gets allocated and freed in
  * fanotify_handle_event() since we wait there for user response. When the
@@ -40,7 +39,12 @@ FANOTIFY_PE(struct fsnotify_event *fse)
 {
        return container_of(fse, struct fanotify_perm_event_info, fae.fse);
 }
-#endif
+
+static inline bool fanotify_is_perm_event(u32 mask)
+{
+       return IS_ENABLED(CONFIG_FANOTIFY_ACCESS_PERMISSIONS) &&
+               mask & FAN_ALL_PERM_EVENTS;
+}
 
 static inline struct fanotify_event_info *FANOTIFY_E(struct fsnotify_event *fse)
 {
index 907a481ac78158612ce918e4a1f4c46ea860fb30..a434de023c49a1b5c26013338778cc7b392e7384 100644 (file)
@@ -142,7 +142,6 @@ static int fill_event_metadata(struct fsnotify_group *group,
        return ret;
 }
 
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
 static struct fanotify_perm_event_info *dequeue_event(
                                struct fsnotify_group *group, int fd)
 {
@@ -199,7 +198,6 @@ static int process_access_response(struct fsnotify_group *group,
 
        return 0;
 }
-#endif
 
 static ssize_t copy_event_to_user(struct fsnotify_group *group,
                                  struct fsnotify_event *event,
@@ -221,10 +219,8 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
                         fanotify_event_metadata.event_len))
                goto out_close_fd;
 
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       if (event->mask & FAN_ALL_PERM_EVENTS)
+       if (fanotify_is_perm_event(event->mask))
                FANOTIFY_PE(event)->fd = fd;
-#endif
 
        if (fd != FAN_NOFD)
                fd_install(fd, f);
@@ -309,10 +305,9 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
                 * Permission events get queued to wait for response.  Other
                 * events can be destroyed now.
                 */
-               if (!(kevent->mask & FAN_ALL_PERM_EVENTS)) {
+               if (!fanotify_is_perm_event(kevent->mask)) {
                        fsnotify_destroy_event(group, kevent);
                } else {
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
                        if (ret <= 0) {
                                FANOTIFY_PE(kevent)->response = FAN_DENY;
                                wake_up(&group->fanotify_data.access_waitq);
@@ -322,7 +317,6 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
                                        &group->fanotify_data.access_list);
                                spin_unlock(&group->notification_lock);
                        }
-#endif
                }
                if (ret < 0)
                        break;
@@ -338,11 +332,13 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
 
 static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t count, loff_t *pos)
 {
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
        struct fanotify_response response = { .fd = -1, .response = -1 };
        struct fsnotify_group *group;
        int ret;
 
+       if (!IS_ENABLED(CONFIG_FANOTIFY_ACCESS_PERMISSIONS))
+               return -EINVAL;
+
        group = file->private_data;
 
        if (count > sizeof(response))
@@ -358,16 +354,11 @@ static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t
                count = ret;
 
        return count;
-#else
-       return -EINVAL;
-#endif
 }
 
 static int fanotify_release(struct inode *ignored, struct file *file)
 {
        struct fsnotify_group *group = file->private_data;
-
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
        struct fanotify_perm_event_info *event, *next;
        struct fsnotify_event *fsn_event;
 
@@ -403,14 +394,14 @@ static int fanotify_release(struct inode *ignored, struct file *file)
                        spin_unlock(&group->notification_lock);
                        fsnotify_destroy_event(group, fsn_event);
                        spin_lock(&group->notification_lock);
-               } else
+               } else {
                        FANOTIFY_PE(fsn_event)->response = FAN_ALLOW;
+               }
        }
        spin_unlock(&group->notification_lock);
 
        /* Response for all permission events it set, wakeup waiters */
        wake_up(&group->fanotify_data.access_waitq);
-#endif
 
        /* matches the fanotify_init->fsnotify_alloc_group */
        fsnotify_destroy_group(group);
@@ -768,10 +759,8 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
        if (force_o_largefile())
                event_f_flags |= O_LARGEFILE;
        group->fanotify_data.f_flags = event_f_flags;
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
        init_waitqueue_head(&group->fanotify_data.access_waitq);
        INIT_LIST_HEAD(&group->fanotify_data.access_list);
-#endif
        switch (flags & FAN_ALL_CLASS_BITS) {
        case FAN_CLASS_NOTIF:
                group->priority = FS_PRIO_0;
@@ -825,6 +814,7 @@ SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags,
        struct fsnotify_group *group;
        struct fd f;
        struct path path;
+       u32 valid_mask = FAN_ALL_EVENTS | FAN_EVENT_ON_CHILD;
        int ret;
 
        pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n",
@@ -855,11 +845,10 @@ SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags,
                mask &= ~FAN_ONDIR;
        }
 
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       if (mask & ~(FAN_ALL_EVENTS | FAN_ALL_PERM_EVENTS | FAN_EVENT_ON_CHILD))
-#else
-       if (mask & ~(FAN_ALL_EVENTS | FAN_EVENT_ON_CHILD))
-#endif
+       if (IS_ENABLED(CONFIG_FANOTIFY_ACCESS_PERMISSIONS))
+               valid_mask |= FAN_ALL_PERM_EVENTS;
+
+       if (mask & ~valid_mask)
                return -EINVAL;
 
        f = fdget(fanotify_fd);
@@ -949,10 +938,10 @@ static int __init fanotify_user_setup(void)
 {
        fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, SLAB_PANIC);
        fanotify_event_cachep = KMEM_CACHE(fanotify_event_info, SLAB_PANIC);
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       fanotify_perm_event_cachep = KMEM_CACHE(fanotify_perm_event_info,
-                                               SLAB_PANIC);
-#endif
+       if (IS_ENABLED(CONFIG_FANOTIFY_ACCESS_PERMISSIONS)) {
+               fanotify_perm_event_cachep =
+                       KMEM_CACHE(fanotify_perm_event_info, SLAB_PANIC);
+       }
 
        return 0;
 }
index 20a57bac38f20e1ad51537ff3f38fca61f939081..744e2b9969fccad69ff9eb349cfdd421d2418794 100644 (file)
@@ -183,11 +183,9 @@ struct fsnotify_group {
 #endif
 #ifdef CONFIG_FANOTIFY
                struct fanotify_group_private_data {
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
                        /* allows a group to block waiting for a userspace response */
                        struct list_head access_list;
                        wait_queue_head_t access_waitq;
-#endif /* CONFIG_FANOTIFY_ACCESS_PERMISSIONS */
                        int f_flags;
                        unsigned int max_marks;
                        struct user_struct *user;