Commit addebd9a authored by Keith Busch's avatar Keith Busch Committed by Jens Axboe
Browse files

fs: don't randomize struct kiocb fields 



This is a size sensitive structure and randomizing can introduce extra
padding that breaks io_uring's fixed size expectations. There are few
fields here as it is, half of which need a fixed order to optimally
pack, so the randomization isn't providing much.

Suggested-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/io-uring/b6f508ca-b1b2-5f40-7998-e4cff1cf7212@kernel.dk/


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent da2634e8

include/linux/fs.h

+0 −5
Original line number Diff line number Diff line
@@ -339,17 +339,12 @@ enum rw_hint { 


struct kiocb {

	struct file		*ki_filp;



	/* The 'ki_filp' pointer is shared in a union for aio */

	randomized_struct_fields_start



	loff_t			ki_pos;

	void (*ki_complete)(struct kiocb *iocb, long ret);

	void			*private;

	int			ki_flags;

	u16			ki_ioprio; /* See linux/ioprio.h */

	struct wait_page_queue	*ki_waitq; /* for async buffered IO */

	randomized_struct_fields_end

};



static inline bool is_sync_kiocb(struct kiocb *kiocb)