diff options
| author | Anuj Gupta | 2022-09-30 11:57:39 +0530 |
|---|---|---|
| committer | Jens Axboe | 2022-09-30 07:50:59 -0600 |
| commit | 9cda70f622cdcf049521a9c2886e5fd8a90a0591 (patch) | |
| tree | 4b56fa2929bfb24a0211c20e561a55453c041878 /io_uring | |
| parent | a9216fac3ed8819cbbda5d39dd5fcaa43dfd35d8 (diff) | |
io_uring: introduce fixed buffer support for io_uring_cmd
Add IORING_URING_CMD_FIXED flag that is to be used for sending io_uring
command with previously registered buffers. User-space passes the buffer
index in sqe->buf_index, same as done in read/write variants that uses
fixed buffers.
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20220930062749.152261-3-anuj20.g@samsung.com
[axboe: shuffle valid flags check before acting on it]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/uring_cmd.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c index 6a6d69523d75..e50de0b6b9f8 100644 --- a/io_uring/uring_cmd.c +++ b/io_uring/uring_cmd.c @@ -4,6 +4,7 @@ #include <linux/file.h> #include <linux/io_uring.h> #include <linux/security.h> +#include <linux/nospec.h> #include <uapi/linux/io_uring.h> @@ -77,8 +78,24 @@ int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); - if (sqe->rw_flags || sqe->__pad1) + if (sqe->__pad1) return -EINVAL; + + ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags); + if (ioucmd->flags & ~IORING_URING_CMD_FIXED) + return -EINVAL; + + if (ioucmd->flags & IORING_URING_CMD_FIXED) { + struct io_ring_ctx *ctx = req->ctx; + u16 index; + + req->buf_index = READ_ONCE(sqe->buf_index); + if (unlikely(req->buf_index >= ctx->nr_user_bufs)) + return -EFAULT; + index = array_index_nospec(req->buf_index, ctx->nr_user_bufs); + req->imu = ctx->user_bufs[index]; + io_req_set_rsrc_node(req, ctx, 0); + } ioucmd->cmd = sqe->cmd; ioucmd->cmd_op = READ_ONCE(sqe->cmd_op); return 0; |