[security] Go 1.17.5 and Go 1.16.12 are released

[Alex Rakoczy]

Hello gophers,

We have just released Go versions 1.17.5 and 1.16.12, minor point releases.

These minor releases include two security fixes following the security policy:

• net/http: limit growth of header canonicalization cache
  
  An attacker can cause unbounded memory growth in a Go server accepting HTTP/2 requests.

For users who cannot immediately update to the new release, setting the GODEBUG=http2server=0 environment variable before calling Serve will disable HTTP/2 unless it was manually configured through the golang.org/x/net/http2 package.

This issue is also fixed in golang.org/x/net/http2 v0.0.0-20211209124913-491a49abca63, for users manually configuring HTTP/2.

Thank you to murakmii for reporting this issue.

This is CVE-2021-44716 and Go issue go.dev/issue/50058.

• syscall: don’t close fd 0 on ForkExec error
  
  When a Go program running on a Unix system is out of file descriptors and calls syscall.ForkExec (including indirectly by using the os/exec package), syscall.ForkExec can close file descriptor 0 as it fails. If this happens (or can be provoked) repeatedly, it can result in misdirected I/O such as writing network traffic intended for one connection to a different connection, or content intended for one file to a different one.
  
  For users who cannot immediately update to the new release, the bug can be mitigated by raising the per-process file descriptor limit.
  
  Thank you to Tomasz Maczukin and Kamil Trzciński of GitLab for reporting this issue.
  
  This is CVE-2021-44717 and Go issue go.dev/issue/50057.

View the release notes for more information:
    https://golang.org/doc/devel/release.html#go1.17.minor

You can download binary and source distributions from the Go web site:
    https://golang.org/dl/

To compile from source using a Git clone, update to the release with
"git checkout go1.17.5" and build as usual.

Thanks to everyone who contributed to the releases.

Cheers,
Alex and Filippo for the Go team