Unverified Commit dd2d6b7f authored by Luis Henriques's avatar Luis Henriques Committed by Christian Brauner
Browse files

fs: drop assert in file_seek_cur_needs_f_lock 



The assert in function file_seek_cur_needs_f_lock() can be triggered very
easily because there are many users of vfs_llseek() (such as overlayfs)
that do their custom locking around llseek instead of relying on
fdget_pos(). Just drop the overzealous assertion.

Fixes: da06e3c5 ("fs: don't needlessly acquire f_lock")
Suggested-by: default avatarJan Kara <jack@suse.cz>
Suggested-by: default avatarMateusz Guzik <mjguzik@gmail.com>
Signed-off-by: default avatarLuis Henriques <luis@igalia.com>
Link: https://lore.kernel.org/20250613101111.17716-1-luis@igalia.com


Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 0b9d62a4

fs/file.c

+6 −2
Original line number Diff line number Diff line
@@ -1198,8 +1198,12 @@ bool file_seek_cur_needs_f_lock(struct file *file) 
	if (!(file->f_mode & FMODE_ATOMIC_POS) && !file->f_op->iterate_shared)

		return false;



	VFS_WARN_ON_ONCE((file_count(file) > 1) &&

			 !mutex_is_locked(&file->f_pos_lock));

	/*

	 * Note that we are not guaranteed to be called after fdget_pos() on

	 * this file obj, in which case the caller is expected to provide the

	 * appropriate locking.

	 */



	return true;

}