Commit bdb2c48e authored Jul 07, 2022 by Pavel Begunkov Committed by Jens Axboe Jul 07, 2022

io_uring: explicit sqe padding for ioctl commands



32 bit sqe->cmd_op is an union with 64 bit values. It's always a good
idea to do padding explicitly. Also zero check it in prep, so it can be
used in the future if needed without compatibility concerns.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e6b95a05e970af79000435166185e85b196b2ba2.1657202417.git.asml.silence@gmail.com


[axboe: turn bitwise OR into logical variant]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 09007af2

fs/io_uring.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -5066,7 +5066,7 @@ static int io_uring_cmd_prep(struct io_kiocb *req,
		{
		struct io_uring_cmd *ioucmd = &req->uring_cmd;

		if (sqe->rw_flags)
		if (sqe->rw_flags \|\| sqe->__pad1)
		return -EINVAL;
		ioucmd->cmd = sqe->cmd;
		ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);

include/uapi/linux/io_uring.h

+4 −1

Original line number	Diff line number	Diff line
		@@ -22,7 +22,10 @@ struct io_uring_sqe {
		union {
		__u64 off; /* offset into file */
		__u64 addr2;
		struct {
		__u32 cmd_op;
		__u32 __pad1;
		};
		};
		union {
		__u64 addr; /* pointer to buffer or iovecs */