1 files changed, 102 insertions, 17 deletions
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index 278620e063ab..454d8e466958 100644
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -108,38 +108,35 @@ static inline void fsnotify_dentry(struct dentry *dentry, __u32 mask)
 	fsnotify_parent(dentry, mask, dentry, FSNOTIFY_EVENT_DENTRY);
 }
 
-static inline int fsnotify_file(struct file *file, __u32 mask)
+static inline int fsnotify_path(const struct path *path, __u32 mask)
 {
-	const struct path *path;
+	return fsnotify_parent(path->dentry, mask, path, FSNOTIFY_EVENT_PATH);
+}
 
+static inline int fsnotify_file(struct file *file, __u32 mask)
+{
 	/*
 	 * FMODE_NONOTIFY are fds generated by fanotify itself which should not
 	 * generate new events. We also don't want to generate events for
 	 * FMODE_PATH fds (involves open & close events) as they are just
 	 * handle creation / destruction events and not "real" file events.
 	 */
-	if (file->f_mode & (FMODE_NONOTIFY | FMODE_PATH))
+	if (FMODE_FSNOTIFY_NONE(file->f_mode))
 		return 0;
 
-	path = &file->f_path;
-	/* Permission events require group prio >= FSNOTIFY_PRIO_CONTENT */
-	if (mask & ALL_FSNOTIFY_PERM_EVENTS &&
-	    !fsnotify_sb_has_priority_watchers(path->dentry->d_sb,
-					       FSNOTIFY_PRIO_CONTENT))
-		return 0;
-
-	return fsnotify_parent(path->dentry, mask, path, FSNOTIFY_EVENT_PATH);
+	return fsnotify_path(&file->f_path, mask);
 }
 
 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+
+void file_set_fsnotify_mode_from_watchers(struct file *file);
+
 /*
  * fsnotify_file_area_perm - permission hook before access to file range
  */
 static inline int fsnotify_file_area_perm(struct file *file, int perm_mask,
 					  const loff_t *ppos, size_t count)
 {
-	__u32 fsnotify_mask = FS_ACCESS_PERM;
-
 	/*
 	 * filesystem may be modified in the context of permission events
 	 * (e.g. by HSM filling a file on access), so sb freeze protection
@@ -147,14 +144,64 @@ static inline int fsnotify_file_area_perm(struct file *file, int perm_mask,
 	 */
 	lockdep_assert_once(file_write_not_started(file));
 
+	if (!(perm_mask & (MAY_READ | MAY_WRITE | MAY_ACCESS)))
+		return 0;
+
+	if (likely(!FMODE_FSNOTIFY_PERM(file->f_mode)))
+		return 0;
+
+	/*
+	 * read()/write() and other types of access generate pre-content events.
+	 */
+	if (unlikely(FMODE_FSNOTIFY_HSM(file->f_mode))) {
+		int ret = fsnotify_pre_content(&file->f_path, ppos, count);
+
+		if (ret)
+			return ret;
+	}
+
 	if (!(perm_mask & MAY_READ))
 		return 0;
 
-	return fsnotify_file(file, fsnotify_mask);
+	/*
+	 * read() also generates the legacy FS_ACCESS_PERM event, so content
+	 * scanners can inspect the content filled by pre-content event.
+	 */
+	return fsnotify_path(&file->f_path, FS_ACCESS_PERM);
+}
+
+/*
+ * fsnotify_mmap_perm - permission hook before mmap of file range
+ */
+static inline int fsnotify_mmap_perm(struct file *file, int prot,
+				     const loff_t off, size_t len)
+{
+	/*
+	 * mmap() generates only pre-content events.
+	 */
+	if (!file || likely(!FMODE_FSNOTIFY_HSM(file->f_mode)))
+		return 0;
+
+	return fsnotify_pre_content(&file->f_path, &off, len);
 }
 
 /*
- * fsnotify_file_perm - permission hook before file access
+ * fsnotify_truncate_perm - permission hook before file truncate
+ */
+static inline int fsnotify_truncate_perm(const struct path *path, loff_t length)
+{
+	struct inode *inode = d_inode(path->dentry);
+
+	if (!(inode->i_sb->s_iflags & SB_I_ALLOW_HSM) ||
+	    !fsnotify_sb_has_priority_watchers(inode->i_sb,
+					       FSNOTIFY_PRIO_PRE_CONTENT))
+		return 0;
+
+	return fsnotify_pre_content(path, &length, 0);
+}
+
+/*
+ * fsnotify_file_perm - permission hook before file access (unknown range)
  */
 static inline int fsnotify_file_perm(struct file *file, int perm_mask)
 {
@@ -168,22 +215,40 @@ static inline int fsnotify_open_perm(struct file *file)
 {
 	int ret;
 
+	if (likely(!FMODE_FSNOTIFY_PERM(file->f_mode)))
+		return 0;
+
 	if (file->f_flags & __FMODE_EXEC) {
-		ret = fsnotify_file(file, FS_OPEN_EXEC_PERM);
+		ret = fsnotify_path(&file->f_path, FS_OPEN_EXEC_PERM);
 		if (ret)
 			return ret;
 	}
 
-	return fsnotify_file(file, FS_OPEN_PERM);
+	return fsnotify_path(&file->f_path, FS_OPEN_PERM);
 }
 
 #else
+static inline void file_set_fsnotify_mode_from_watchers(struct file *file)
+{
+}
+
 static inline int fsnotify_file_area_perm(struct file *file, int perm_mask,
 					  const loff_t *ppos, size_t count)
 {
 	return 0;
 }
 
+static inline int fsnotify_mmap_perm(struct file *file, int prot,
+				     const loff_t off, size_t len)
+{
+	return 0;
+}
+
+static inline int fsnotify_truncate_perm(const struct path *path, loff_t length)
+{
+	return 0;
+}
+
 static inline int fsnotify_file_perm(struct file *file, int perm_mask)
 {
 	return 0;
@@ -255,6 +320,11 @@ static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
 	__fsnotify_vfsmount_delete(mnt);
 }
 
+static inline void fsnotify_mntns_delete(struct mnt_namespace *mntns)
+{
+	__fsnotify_mntns_delete(mntns);
+}
+
 /*
  * fsnotify_inoderemove - an inode is going away
  */
@@ -463,4 +533,19 @@ static inline int fsnotify_sb_error(struct super_block *sb, struct inode *inode,
 			NULL, NULL, NULL, 0);
 }
 
+static inline void fsnotify_mnt_attach(struct mnt_namespace *ns, struct vfsmount *mnt)
+{
+	fsnotify_mnt(FS_MNT_ATTACH, ns, mnt);
+}
+
+static inline void fsnotify_mnt_detach(struct mnt_namespace *ns, struct vfsmount *mnt)
+{
+	fsnotify_mnt(FS_MNT_DETACH, ns, mnt);
+}
+
+static inline void fsnotify_mnt_move(struct mnt_namespace *ns, struct vfsmount *mnt)
+{
+	fsnotify_mnt(FS_MNT_MOVE, ns, mnt);
+}
+
 #endif	/* _LINUX_FS_NOTIFY_H */