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https://github.com/golang/go
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e64f3f211a
The system call takes an int, but the kernel stores it in a uint16. At least one Linux system sets /proc/sys/net/core/somaxconn to 262144, which ends up being 0 in the uint16. Avoid being tricked. FreeBSD sources also store the backlog in a uint16. Assume the problem is systemic and fix it everywhere. Fixes #5030. R=golang-dev, bradfitz CC=golang-dev https://golang.org/cl/7480046
32 lines
648 B
Go
32 lines
648 B
Go
// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package net
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import "syscall"
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func maxListenerBacklog() int {
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fd, err := open("/proc/sys/net/core/somaxconn")
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if err != nil {
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return syscall.SOMAXCONN
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}
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defer fd.close()
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l, ok := fd.readLine()
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if !ok {
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return syscall.SOMAXCONN
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}
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f := getFields(l)
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n, _, ok := dtoi(f[0], 0)
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if n == 0 || !ok {
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return syscall.SOMAXCONN
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}
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// Linux stores the backlog in a uint16.
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// Truncate number to avoid wrapping.
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// See issue 5030.
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if n > 1<<16-1 {
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n = 1<<16 - 1
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}
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return n
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}
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