Introduce a socket-specific io_uring_cmd to support getsockname/getpeername via io_uring. I made this an io_uring_cmd instead of a new operation to avoid polluting the command namespace with what is exclusively a socket operation. In addition, since we don't need to conform to existing interfaces, this merges the getsockname/getpeername in a single operation, since the implementation is pretty much the same. This has been frequently requested, for instance at [1] and more recently in the project Discord channel. The main use-case is to support fixed socket file descriptors. [1] https://github.com/axboe/liburing/issues/1356 Signed-off-by: Gabriel Krisman Bertazi --- include/uapi/linux/io_uring.h | 1 + io_uring/cmd_net.c | 24 ++++++++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 263bed13473e..6bab32efabef 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -1001,6 +1001,7 @@ enum io_uring_socket_op { SOCKET_URING_OP_GETSOCKOPT, SOCKET_URING_OP_SETSOCKOPT, SOCKET_URING_OP_TX_TIMESTAMP, + SOCKET_URING_OP_GETSOCKNAME, }; /* diff --git a/io_uring/cmd_net.c b/io_uring/cmd_net.c index 27a09aa4c9d0..092844358729 100644 --- a/io_uring/cmd_net.c +++ b/io_uring/cmd_net.c @@ -132,6 +132,28 @@ static int io_uring_cmd_timestamp(struct socket *sock, return -EAGAIN; } +static int io_uring_cmd_getsockname(struct socket *sock, + struct io_uring_cmd *cmd, + unsigned int issue_flags) +{ + const struct io_uring_sqe *sqe = cmd->sqe; + + struct sockaddr_storage address; + struct sockaddr __user *uaddr; + int __user *ulen; + unsigned int peer; + + uaddr = u64_to_user_ptr(READ_ONCE(sqe->addr)); + ulen = u64_to_user_ptr(sqe->addr3); + peer = READ_ONCE(sqe->optlen); + + if (sqe->ioprio || sqe->__pad1 || sqe->len || sqe->rw_flags) + return -EINVAL; + if (peer > 1) + return -EINVAL; + return do_getsockname(sock, &address, 0, uaddr, ulen); +} + int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags) { struct socket *sock = cmd->file->private_data; @@ -159,6 +181,8 @@ int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags) return io_uring_cmd_setsockopt(sock, cmd, issue_flags); case SOCKET_URING_OP_TX_TIMESTAMP: return io_uring_cmd_timestamp(sock, cmd, issue_flags); + case SOCKET_URING_OP_GETSOCKNAME: + return io_uring_cmd_getsockname(sock, cmd, issue_flags); default: return -EOPNOTSUPP; } -- 2.51.0