Like IORING_OP_READV, this is limited to supporting just a single
segment in the iovec passed in.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
fs/io_uring.c | 115 ++++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 103 insertions(+), 12 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 561120460422..fadffe21d4da 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -44,6 +44,7 @@
#include <linux/errno.h>
#include <linux/syscalls.h>
#include <linux/compat.h>
+#include <net/compat.h>
#include <linux/refcount.h>
#include <linux/uio.h>
#include <linux/bits.h>
@@ -729,6 +730,7 @@ static const struct io_op_def io_op_defs[] = {
.unbound_nonreg_file = 1,
.needs_fs = 1,
.pollin = 1,
+ .buffer_select = 1,
},
[IORING_OP_TIMEOUT] = {
.async_ctx = 1,
@@ -3582,6 +3584,90 @@ static int io_send(struct io_kiocb *req, struct io_kiocb **nxt,
#endif
}
+static int __io_recvmsg_copy_hdr(struct io_kiocb *req, struct io_async_ctx *io)
+{
+ struct io_sr_msg *sr = &req->sr_msg;
+ struct iovec __user *uiov;
+ size_t iov_len;
+ int ret;
+
+ ret = __copy_msghdr_from_user(&io->msg.msg, sr->msg, &io->msg.uaddr,
+ &uiov, &iov_len);
+ if (ret)
+ return ret;
+
+ if (req->flags & REQ_F_BUFFER_SELECT) {
+ if (iov_len > 1)
+ return -EINVAL;
+ if (copy_from_user(io->msg.iov, uiov, sizeof(*uiov)))
+ return -EFAULT;
+ sr->len = io->msg.iov[0].iov_len;
+ iov_iter_init(&io->msg.msg.msg_iter, READ, io->msg.iov, 1,
+ sr->len);
+ io->msg.iov = NULL;
+ } else {
+ ret = import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
+ &io->msg.iov, &io->msg.msg.msg_iter);
+ if (ret > 0)
+ ret = 0;
+ }
+
+ return ret;
+}
+
+#ifdef CONFIG_COMPAT
+static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
+ struct io_async_ctx *io)
+{
+ struct compat_msghdr __user *msg_compat;
+ struct io_sr_msg *sr = &req->sr_msg;
+ struct compat_iovec __user *uiov;
+ compat_uptr_t ptr;
+ compat_size_t len;
+ int ret;
+
+ msg_compat = (struct compat_msghdr __user *) sr->msg;
+ ret = __get_compat_msghdr(&io->msg.msg, msg_compat, &io->msg.uaddr,
+ &ptr, &len);
+
+ uiov = compat_ptr(ptr);
+ if (req->flags & REQ_F_BUFFER_SELECT) {
+ compat_ssize_t clen;
+
+ if (len > 1)
+ return -EINVAL;
+ if (!access_ok(uiov, sizeof(*uiov)))
+ return -EFAULT;
+ if (__get_user(clen, &uiov->iov_len))
+ return -EFAULT;
+ if (clen < 0)
+ return -EINVAL;
+ sr->len = io->msg.iov[0].iov_len;
+ io->msg.iov = NULL;
+ } else {
+ ret = compat_import_iovec(READ, uiov, len, UIO_FASTIOV,
+ &io->msg.iov,
+ &io->msg.msg.msg_iter);
+ if (ret > 0)
+ ret = 0;
+ }
+
+ return 0;
+}
+#endif
+
+static int io_recvmsg_copy_hdr(struct io_kiocb *req, struct io_async_ctx *io)
+{
+ io->msg.iov = io->msg.fast_iov;
+
+#ifdef CONFIG_COMPAT
+ if (req->ctx->compat)
+ return __io_compat_recvmsg_copy_hdr(req, io);
+#endif
+
+ return __io_recvmsg_copy_hdr(req, io);
+}
+
static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
int *cflags, bool needs_lock)
{
@@ -3629,9 +3715,7 @@ static int io_recvmsg_prep(struct io_kiocb *req,
if (req->flags & REQ_F_NEED_CLEANUP)
return 0;
- io->msg.iov = io->msg.fast_iov;
- ret = recvmsg_copy_msghdr(&io->msg.msg, sr->msg, sr->msg_flags,
- &io->msg.uaddr, &io->msg.iov);
+ ret = io_recvmsg_copy_hdr(req, io);
if (!ret)
req->flags |= REQ_F_NEED_CLEANUP;
return ret;
@@ -3646,13 +3730,14 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt,
#if defined(CONFIG_NET)
struct io_async_msghdr *kmsg = NULL;
struct socket *sock;
- int ret;
+ int ret, cflags = 0;
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
sock = sock_from_file(req->file, &ret);
if (sock) {
+ struct io_buffer *kbuf;
struct io_async_ctx io;
unsigned flags;
@@ -3664,19 +3749,23 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt,
kmsg->iov = kmsg->fast_iov;
kmsg->msg.msg_iter.iov = kmsg->iov;
} else {
- struct io_sr_msg *sr = &req->sr_msg;
-
kmsg = &io.msg;
kmsg->msg.msg_name = &io.msg.addr;
- io.msg.iov = io.msg.fast_iov;
- ret = recvmsg_copy_msghdr(&io.msg.msg, sr->msg,
- sr->msg_flags, &io.msg.uaddr,
- &io.msg.iov);
+ ret = io_recvmsg_copy_hdr(req, &io);
if (ret)
return ret;
}
+ kbuf = io_recv_buffer_select(req, &cflags, !force_nonblock);
+ if (IS_ERR(kbuf)) {
+ return PTR_ERR(kbuf);
+ } else if (kbuf) {
+ kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
+ iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->iov,
+ 1, req->sr_msg.len);
+ }
+
flags = req->sr_msg.msg_flags;
if (flags & MSG_DONTWAIT)
req->flags |= REQ_F_NOWAIT;
@@ -3694,7 +3783,7 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt,
if (kmsg && kmsg->iov != kmsg->fast_iov)
kfree(kmsg->iov);
req->flags &= ~REQ_F_NEED_CLEANUP;
- io_cqring_add_event(req, ret);
+ __io_cqring_add_event(req, ret, cflags);
if (ret < 0)
req_set_fail_links(req);
io_put_req_find_next(req, nxt);
@@ -4806,8 +4895,10 @@ static void io_cleanup_req(struct io_kiocb *req)
if (io->rw.iov != io->rw.fast_iov)
kfree(io->rw.iov);
break;
- case IORING_OP_SENDMSG:
case IORING_OP_RECVMSG:
+ if (req->flags & REQ_F_BUFFER_SELECTED)
+ kfree(req->sr_msg.kbuf);
+ case IORING_OP_SENDMSG:
if (io->msg.iov != io->msg.fast_iov)
kfree(io->msg.iov);
break;
--
2.25.1
