psx

Overview ¶

Package psx provides CGo wrappers for two system call functions that work by calling the C libpsx functions of these names. The purpose being to perform system calls symultaneously on all the pthreads of the Go (and CGo) combined runtime. Since Go's runtime freely migrates code execution between pthreads, support of this type is required for any successful attempt to fully drop or modify user privilege of a Go program under Linux. More info on how privilege works can be found here:

https://sites.google.com/site/fullycapable

Correct compilation of this package may require an extra step:

If your Go compiler is pre-go1.15, a workaround may be required to be able to link this package. In order to do what it needs to, this package employs some unusual linking flags. You will need to do this for any Go toolchain that that does not include this patch:

https://go-review.googlesource.com/c/go/+/236139/

As of the time of writing, that is all release tags prior to go1.15beta1 .

The workaround is to build using the CGO_LDFLAGS_ALLOW override as follows:

export CGO_LDFLAGS_ALLOW="-Wl,-?-wrap[=,][^-.@][^,]*"

Copyright (c) 2019,20 Andrew G. Morgan <morgan@kernel.org>