syscall: remove cloexecSocket fallback path

Support for Linux kernel versions requiring the fallback to CloseOnExec
was dropped from recent Go versions. The minimum Linux kernel version is
2.6.32 as of Go 1.18. The SOCK_CLOEXEC flag for the socket syscall is
supported since kernel version 2.6.27.

Follows a similar change for net.sysSocket in CL 403634.

For #45964

Change-Id: I8b6311f07c4ed7900a9af3ecb2e146c49db08665
Reviewed-on: https://go-review.googlesource.com/c/go/+/422374
Reviewed-by: Joedian Reid <joedian@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>

diff --git a/src/syscall/lsf_linux.go b/src/syscall/lsf_linux.go
index 28e96d54e6a195ecb57e1d16511eea6fc73b2bfb..838acc5fb1944e76677b3c879ae79f866b8c29e6 100644 (file)
--- a/src/syscall/lsf_linux.go
+++ b/src/syscall/lsf_linux.go
@@ -48,7 +48,7 @@ type iflags struct {
 
 // Deprecated: Use golang.org/x/net/bpf instead.
 func SetLsfPromisc(name string, m bool) error {
-       s, e := cloexecSocket(AF_INET, SOCK_DGRAM, 0)
+       s, e := Socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC, 0)
        if e != nil {
                return e
        }

diff --git a/src/syscall/netlink_linux.go b/src/syscall/netlink_linux.go
index 2d810705bf1bcd38f162bf5a639244619af6a163..e976c70ef1670ae97987a20733d4e9fefeb0c67e 100644 (file)
--- a/src/syscall/netlink_linux.go
+++ b/src/syscall/netlink_linux.go
@@ -50,7 +50,7 @@ func newNetlinkRouteRequest(proto, seq, family int) []byte {
 // NetlinkRIB returns routing information base, as known as RIB, which
 // consists of network facility information, states and parameters.
 func NetlinkRIB(proto, family int) ([]byte, error) {
-       s, err := cloexecSocket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE)
+       s, err := Socket(AF_NETLINK, SOCK_RAW|SOCK_CLOEXEC, NETLINK_ROUTE)
        if err != nil {
                return nil, err
        }

diff --git a/src/syscall/sock_cloexec_linux.go b/src/syscall/sock_cloexec_linux.go
deleted file mode 100644 (file)
index 600cf25..0000000
--- a/src/syscall/sock_cloexec_linux.go
+++ /dev/null
@@ -1,29 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package syscall
-
-// This is a stripped down version of sysSocket from net/sock_cloexec.go.
-func cloexecSocket(family, sotype, proto int) (int, error) {
-       s, err := Socket(family, sotype|SOCK_CLOEXEC, proto)
-       switch err {
-       case nil:
-               return s, nil
-       default:
-               return -1, err
-       case EINVAL:
-       }
-
-       ForkLock.RLock()
-       s, err = Socket(family, sotype, proto)
-       if err == nil {
-               CloseOnExec(s)
-       }
-       ForkLock.RUnlock()
-       if err != nil {
-               Close(s)
-               return -1, err
-       }
-       return s, nil
-}