unix: check correct group in Faccessat

The Faccessat call checks the user, group, or other permission bits of a
file to see if the calling process can access it. The test to see if the
group permissions should be used was made with the wrong group id, using
the process's group id rather than the file's group id. Fix this to use
the correct group id.

This change only affects Linux versions prior to 5.8. Linux 5.8 added
the faccessat2 system call, which we use in preference to the internal
implementation.

No test since we cannot easily change file permissions when not running
as root and the test is meaningless if running as root.

For golang/go#52313

Change-Id: I6fa64379a50c9380207eab9d095ef7fbd05a2d59
Reviewed-on: https://go-review.googlesource.com/c/sys/+/400074
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
1 file changed
tree: 6764ce975218f52fdef8b531c3c741e118e09778
  1. cpu/
  2. execabs/
  3. internal/
  4. plan9/
  5. unix/
  6. windows/
  7. .gitattributes
  8. .gitignore
  9. AUTHORS
  10. codereview.cfg
  11. CONTRIBUTING.md
  12. CONTRIBUTORS
  13. go.mod
  14. LICENSE
  15. PATENTS
  16. README.md
README.md

sys

Go Reference

This repository holds supplemental Go packages for low-level interactions with the operating system.

Download/Install

The easiest way to install is to run go get -u golang.org/x/sys. You can also manually git clone the repository to $GOPATH/src/golang.org/x/sys.

Report Issues / Send Patches

This repository uses Gerrit for code changes. To learn how to submit changes to this repository, see https://golang.org/doc/contribute.html.

The main issue tracker for the sys repository is located at https://github.com/golang/go/issues. Prefix your issue with “x/sys:” in the subject line, so it is easy to find.