openat2 is a new syscall added to Linux 5.6. It provides a superset of
openat(2) functionality, extending it with flags telling the kernel how
to resolve the paths.
For more info, see https://lwn.net/Articles/803237/
NOTE that this is a second attempt to add the call; the previous one
(https://golang.org/cl/227280) was reverted
(https://golang.org/cl/227846) due to the test case failure on ARM
(https://golang.org/issue/38357).
This CL has the test case reworked to be less assumptive to the testing
environment. In particular, it first tries if the most simplistic
openat2() call succeeds, and skips the test otherwise. It is done that
way because CI can be under under different kernels and in various
envrionments -- in particular, Docker+seccomp can result in EPERM from a
system call (which is not expected otherwise).
For previous discussions about the test case, see
https://golang.org/cl/227865.
Change-Id: I4276cf13dc29ecbdbdc9c58da0f76270f585a67f
Reviewed-on: https://go-review.googlesource.com/c/sys/+/253057
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Linux kernel 5.8 added the faccessat2 syscall taking a flags argument.
Attempt to use it in Faccessat and fall back to the existing
implementation mimicking glibc faccessat.
Tested on Debian Buster with manually built Linux kernel 5.8
Suggested by Ian Lance Taylor.
Change-Id: Ia14f744a63dde7ff2dea34935cabc62937de9cb5
Reviewed-on: https://go-review.googlesource.com/c/sys/+/246537
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
These are Linux-specific system calls for efficiently reading and
writing memory in foreign processes.
A new RemoteIovec type is added for use in these wrappers, as Iovec's
Base field is a pointer, and creating invalid pointers is invalid in
Go.
Change-Id: I329501ab7b4df9d0aebe289369d3a5f77120af02
GitHub-Last-Rev: 262aabed02
GitHub-Pull-Request: golang/sys#74
Reviewed-on: https://go-review.googlesource.com/c/sys/+/243497
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
openat2 is a new syscall added to Linux 5.6. It provides a superset
of openat(2) functionality, providing a way to extend it in the future,
and (for now) adding flags telling the kernel how to resolve the path.
For more info on openat2, see https://lwn.net/Articles/803237/
A primitive test case is added to check that Openat2 works as
it should. Tested to skip on kernel 5.5 and pass on 5.6.
Change-Id: Ib8bbd71791762f043200543cecdea16d2fd3c81d
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Reviewed-on: https://go-review.googlesource.com/c/sys/+/227280
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
