go/misc
Russ Cox 1dcb5836ad cmd/go: accept only limited compiler and linker flags in #cgo directives
Both gcc and clang accept an option -fplugin=code.so to load
a plugin from the ELF shared object file code.so.
Obviously that plugin can then do anything it wants
during the build. This is contrary to the goal of "go get"
never running untrusted code during the build.
(What happens if you choose to run the result of
the build is your responsibility.)

Disallow this behavior by only allowing a small set of
known command-line flags in #cgo CFLAGS directives
(and #cgo LDFLAGS, etc).

The new restrictions can be adjusted by the environment
variables CGO_CFLAGS_ALLOW, CGO_CFLAGS_DISALLOW,
and so on. See the documentation.

In addition to excluding cgo-defined flags, we also have to
make sure that when we pass file names on the command
line, they don't look like flags. So we now refuse to build
packages containing suspicious file names like -x.go.

A wrinkle in all this is that GNU binutils uniformly accept
@foo on the command line to mean "if the file foo exists,
then substitute its contents for @foo in the command line".
So we must also reject @x.go, flags and flag arguments
beginning with @, and so on.

Fixes #23672, CVE-2018-6574.

Change-Id: I59e7c1355155c335a5c5ae0d2cf8fa7aa313940a
Reviewed-on: https://team-review.git.corp.google.com/209949
Reviewed-by: Ian Lance Taylor <iant@google.com>
2018-02-07 15:35:57 +00:00
..
android misc,src: add support for specifying adb flags to the android harness 2018-01-20 21:13:30 +00:00
arm
cgo cmd/go: accept only limited compiler and linker flags in #cgo directives 2018-02-07 15:35:57 +00:00
chrome/gophertool
git
ios misc/ios: dump logs for failing lldb sessions to stdout 2017-12-04 17:48:58 +00:00
linkcheck
nacl cmd/cover: preserve compiler directives in floating comments 2017-10-16 23:38:38 +00:00
sortac
swig cmd/go: fix swig support and run swig tests during run.bash 2017-11-16 17:19:19 +00:00
trace misc/trace: update trace-viewer 2017-08-25 15:50:29 +00:00
benchcmp
editors