From: Dylan Yudaken <[email protected]>
To: Jens Axboe <[email protected]>,
Pavel Begunkov <[email protected]>,
<[email protected]>
Cc: <[email protected]>, <[email protected]>,
Dylan Yudaken <[email protected]>
Subject: [PATCH v2 for-next 03/12] io_uring: allow iov_len = 0 for recvmsg and buffer select
Date: Thu, 30 Jun 2022 02:12:22 -0700 [thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
When using BUFFER_SELECT there is no technical requirement that the user
actually provides iov, and this removes one copy_from_user call.
So allow iov_len to be 0.
Signed-off-by: Dylan Yudaken <[email protected]>
---
io_uring/net.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/io_uring/net.c b/io_uring/net.c
index 19a805c3814c..5e84f7ab92a3 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -300,12 +300,18 @@ static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
return ret;
if (req->flags & REQ_F_BUFFER_SELECT) {
- if (iov_len > 1)
+ if (iov_len == 0) {
+ sr->len = iomsg->fast_iov[0].iov_len = 0;
+ iomsg->fast_iov[0].iov_base = NULL;
+ iomsg->free_iov = NULL;
+ } else if (iov_len > 1) {
return -EINVAL;
- if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
- return -EFAULT;
- sr->len = iomsg->fast_iov[0].iov_len;
- iomsg->free_iov = NULL;
+ } else {
+ if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
+ return -EFAULT;
+ sr->len = iomsg->fast_iov[0].iov_len;
+ iomsg->free_iov = NULL;
+ }
} else {
iomsg->free_iov = iomsg->fast_iov;
ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
--
2.30.2
next prev parent reply other threads:[~2022-06-30 9:18 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-30 9:12 [PATCH v2 for-next 00/12] io_uring: multishot recv Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 01/12] io_uring: allow 0 length for buffer select Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 02/12] io_uring: restore bgid in io_put_kbuf Dylan Yudaken
2022-06-30 9:12 ` Dylan Yudaken [this message]
2022-06-30 9:12 ` [PATCH v2 for-next 04/12] io_uring: recycle buffers on error Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 05/12] io_uring: clean up io_poll_check_events return values Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 06/12] io_uring: add IOU_STOP_MULTISHOT return code Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 07/12] io_uring: add allow_overflow to io_post_aux_cqe Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 08/12] io_uring: fix multishot poll on overflow Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 09/12] io_uring: fix multishot accept ordering Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 10/12] io_uring: multishot recv Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 11/12] io_uring: fix io_uring_cqe_overflow trace format Dylan Yudaken
2022-06-30 9:12 ` [PATCH v2 for-next 12/12] io_uring: only trace one of complete or overflow Dylan Yudaken
2022-06-30 20:19 ` [PATCH v2 for-next 00/12] io_uring: multishot recv Jens Axboe
2022-06-30 20:32 ` Jens Axboe
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