Merge tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull 'struct fd' class updates from Al Viro:
 "The bulk of struct fd memory safety stuff

  Making sure that struct fd instances are destroyed in the same scope
  where they'd been created, getting rid of reassignments and passing
  them by reference, converting to CLASS(fd{,_pos,_raw}).

  We are getting very close to having the memory safety of that stuff
  trivial to verify"

* tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits)
  deal with the last remaing boolean uses of fd_file()
  css_set_fork(): switch to CLASS(fd_raw, ...)
  memcg_write_event_control(): switch to CLASS(fd)
  assorted variants of irqfd setup: convert to CLASS(fd)
  do_pollfd(): convert to CLASS(fd)
  convert do_select()
  convert vfs_dedupe_file_range().
  convert cifs_ioctl_copychunk()
  convert media_request_get_by_fd()
  convert spu_run(2)
  switch spufs_calls_{get,put}() to CLASS() use
  convert cachestat(2)
  convert do_preadv()/do_pwritev()
  fdget(), more trivial conversions
  fdget(), trivial conversions
  privcmd_ioeventfd_assign(): don't open-code eventfd_ctx_fdget()
  o2hb_region_dev_store(): avoid goto around fdget()/fdput()
  introduce "fd_pos" class, convert fdget_pos() users to it.
  fdget_raw() users: switch to CLASS(fd_raw)
  convert vmsplice() to CLASS(fd)
  ...

2 files changed, 28 insertions, 54 deletions

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 61b83039771e..35159fa0b063 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -1002,22 +1002,17 @@ static int fanotify_find_path(int dfd, const char __user *filename,
 		 dfd, filename, flags);
 
 	if (filename == NULL) {
-		struct fd f = fdget(dfd);
+		CLASS(fd, f)(dfd);
 
-		ret = -EBADF;
-		if (!fd_file(f))
-			goto out;
+		if (fd_empty(f))
+			return -EBADF;
 
-		ret = -ENOTDIR;
 		if ((flags & FAN_MARK_ONLYDIR) &&
-		    !(S_ISDIR(file_inode(fd_file(f))->i_mode))) {
-			fdput(f);
-			goto out;
-		}
+		    !(S_ISDIR(file_inode(fd_file(f))->i_mode)))
+			return -ENOTDIR;
 
 		*path = fd_file(f)->f_path;
 		path_get(path);
-		fdput(f);
 	} else {
 		unsigned int lookup_flags = 0;
 
@@ -1681,7 +1676,6 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	struct inode *inode = NULL;
 	struct vfsmount *mnt = NULL;
 	struct fsnotify_group *group;
-	struct fd f;
 	struct path path;
 	struct fan_fsid __fsid, *fsid = NULL;
 	u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS;
@@ -1751,14 +1745,13 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 		umask = FANOTIFY_EVENT_FLAGS;
 	}
 
-	f = fdget(fanotify_fd);
-	if (unlikely(!fd_file(f)))
+	CLASS(fd, f)(fanotify_fd);
+	if (fd_empty(f))
 		return -EBADF;
 
 	/* verify that this is indeed an fanotify instance */
-	ret = -EINVAL;
 	if (unlikely(fd_file(f)->f_op != &fanotify_fops))
-		goto fput_and_out;
+		return -EINVAL;
 	group = fd_file(f)->private_data;
 
 	/*
@@ -1766,23 +1759,21 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	 * marks.  This also includes setting up such marks by a group that
 	 * was initialized by an unprivileged user.
 	 */
-	ret = -EPERM;
 	if ((!capable(CAP_SYS_ADMIN) ||
 	     FAN_GROUP_FLAG(group, FANOTIFY_UNPRIV)) &&
 	    mark_type != FAN_MARK_INODE)
-		goto fput_and_out;
+		return -EPERM;
 
 	/*
 	 * Permission events require minimum priority FAN_CLASS_CONTENT.
 	 */
-	ret = -EINVAL;
 	if (mask & FANOTIFY_PERM_EVENTS &&
 	    group->priority < FSNOTIFY_PRIO_CONTENT)
-		goto fput_and_out;
+		return -EINVAL;
 
 	if (mask & FAN_FS_ERROR &&
 	    mark_type != FAN_MARK_FILESYSTEM)
-		goto fput_and_out;
+		return -EINVAL;
 
 	/*
 	 * Evictable is only relevant for inode marks, because only inode object
@@ -1790,7 +1781,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	 */
 	if (flags & FAN_MARK_EVICTABLE &&
 	     mark_type != FAN_MARK_INODE)
-		goto fput_and_out;
+		return -EINVAL;
 
 	/*
 	 * Events that do not carry enough information to report
@@ -1802,7 +1793,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS);
 	if (mask & ~(FANOTIFY_FD_EVENTS|FANOTIFY_EVENT_FLAGS) &&
 	    (!fid_mode || mark_type == FAN_MARK_MOUNT))
-		goto fput_and_out;
+		return -EINVAL;
 
 	/*
 	 * FAN_RENAME uses special info type records to report the old and
@@ -1810,23 +1801,22 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	 * useful and was not implemented.
 	 */
 	if (mask & FAN_RENAME && !(fid_mode & FAN_REPORT_NAME))
-		goto fput_and_out;
+		return -EINVAL;
 
 	if (mark_cmd == FAN_MARK_FLUSH) {
-		ret = 0;
 		if (mark_type == FAN_MARK_MOUNT)
 			fsnotify_clear_vfsmount_marks_by_group(group);
 		else if (mark_type == FAN_MARK_FILESYSTEM)
 			fsnotify_clear_sb_marks_by_group(group);
 		else
 			fsnotify_clear_inode_marks_by_group(group);
-		goto fput_and_out;
+		return 0;
 	}
 
 	ret = fanotify_find_path(dfd, pathname, &path, flags,
 			(mask & ALL_FSNOTIFY_EVENTS), obj_type);
 	if (ret)
-		goto fput_and_out;
+		return ret;
 
 	if (mark_cmd == FAN_MARK_ADD) {
 		ret = fanotify_events_supported(group, &path, mask, flags);
@@ -1905,8 +1895,6 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 
 path_put_and_out:
 	path_put(&path);
-fput_and_out:
-	fdput(f);
 	return ret;
 }
 
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 0794dcaf1e47..e0c48956608a 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -732,7 +732,6 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
 	struct fsnotify_group *group;
 	struct inode *inode;
 	struct path path;
-	struct fd f;
 	int ret;
 	unsigned flags = 0;
 
@@ -752,21 +751,17 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
 	if (unlikely(!(mask & ALL_INOTIFY_BITS)))
 		return -EINVAL;
 
-	f = fdget(fd);
-	if (unlikely(!fd_file(f)))
+	CLASS(fd, f)(fd);
+	if (fd_empty(f))
 		return -EBADF;
 
 	/* IN_MASK_ADD and IN_MASK_CREATE don't make sense together */
-	if (unlikely((mask & IN_MASK_ADD) && (mask & IN_MASK_CREATE))) {
-		ret = -EINVAL;
-		goto fput_and_out;
-	}
+	if (unlikely((mask & IN_MASK_ADD) && (mask & IN_MASK_CREATE)))
+		return -EINVAL;
 
 	/* verify that this is indeed an inotify instance */
-	if (unlikely(fd_file(f)->f_op != &inotify_fops)) {
-		ret = -EINVAL;
-		goto fput_and_out;
-	}
+	if (unlikely(fd_file(f)->f_op != &inotify_fops))
+		return -EINVAL;
 
 	if (!(mask & IN_DONT_FOLLOW))
 		flags |= LOOKUP_FOLLOW;
@@ -776,7 +771,7 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
 	ret = inotify_find_inode(pathname, &path, flags,
 			(mask & IN_ALL_EVENTS));
 	if (ret)
-		goto fput_and_out;
+		return ret;
 
 	/* inode held in place by reference to path; group by fget on fd */
 	inode = path.dentry->d_inode;
@@ -785,8 +780,6 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
 	/* create/update an inode mark */
 	ret = inotify_update_watch(group, inode, mask);
 	path_put(&path);
-fput_and_out:
-	fdput(f);
 	return ret;
 }
 
@@ -794,33 +787,26 @@ SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd)
 {
 	struct fsnotify_group *group;
 	struct inotify_inode_mark *i_mark;
-	struct fd f;
-	int ret = -EINVAL;
+	CLASS(fd, f)(fd);
 
-	f = fdget(fd);
-	if (unlikely(!fd_file(f)))
+	if (fd_empty(f))
 		return -EBADF;
 
 	/* verify that this is indeed an inotify instance */
 	if (unlikely(fd_file(f)->f_op != &inotify_fops))
-		goto out;
+		return -EINVAL;
 
 	group = fd_file(f)->private_data;
 
 	i_mark = inotify_idr_find(group, wd);
 	if (unlikely(!i_mark))
-		goto out;
-
-	ret = 0;
+		return -EINVAL;
 
 	fsnotify_destroy_mark(&i_mark->fsn_mark, group);
 
 	/* match ref taken by inotify_idr_find */
 	fsnotify_put_mark(&i_mark->fsn_mark);
-
-out:
-	fdput(f);
-	return ret;
+	return 0;
 }
 
 /*