16 Commits

Author SHA1 Message Date
Andrew G. Morgan
94eda9ae37 syscall: disable TestAllThreadsSyscall on linux-ppc64
For some reason, currently unknown, this test case fails exclusively
on the linux-ppc64 platform. Until such time as it can be made to
work, we'll disable this test case on that platform.

The same issue causes TestSetuidEtc to fail too, so disable that
on this platform.

Updates #42178

Change-Id: Idd3f6c2ee9f2fba2eb8ce4de69de7f316858bb15
Reviewed-on: https://go-review.googlesource.com/c/go/+/264719
Trust: Emmanuel Odeke <emm.odeke@gmail.com>
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-10-24 03:06:05 +00:00
Andrew G. Morgan
d1b1145cac syscall: support POSIX semantics for Linux syscalls
This change adds two new methods for invoking system calls
under Linux: syscall.AllThreadsSyscall() and
syscall.AllThreadsSyscall6().

These system call wrappers ensure that all OSThreads mirror
a common system call. The wrappers serialize execution of the
runtime to ensure no race conditions where any Go code observes
a non-atomic OS state change. As such, the syscalls have
higher runtime overhead than regular system calls, and only
need to be used where such thread (or 'm' in the parlance
of the runtime sources) consistency is required.

The new support is used to enable these functions under Linux:

  syscall.Setegid(), syscall.Seteuid(), syscall.Setgroups(),
  syscall.Setgid(), syscall.Setregid(), syscall.Setreuid(),
  syscall.Setresgid(), syscall.Setresuid() and syscall.Setuid().

They work identically to their glibc counterparts.

Extensive discussion of the background issue addressed in this
patch can be found here:

   https://github.com/golang/go/issues/1435

In the case where cgo is used, the C runtime can launch pthreads that
are not managed by the Go runtime. As such, the added
syscall.AllThreadsSyscall*() return ENOTSUP when cgo is enabled.
However, for the 9 syscall.Set*() functions listed above, when cgo is
active, these functions redirect to invoke their C.set*() equivalents
in glibc, which wraps the raw system calls with a nptl:setxid fixup
mechanism. This achieves POSIX semantics for these functions in the
combined Go and C runtime.

As a side note, the glibc/nptl:setxid support (2019-11-30) does not
extend to all security related system calls under Linux so using
native Go (CGO_ENABLED=0) and these AllThreadsSyscall*()s, where
needed, will yield more well defined/consistent behavior over all
threads of a Go program. That is, using the
syscall.AllThreadsSyscall*() wrappers for things like setting state
through SYS_PRCTL and SYS_CAPSET etc.

Fixes #1435

Change-Id: Ib1a3e16b9180f64223196a32fc0f9dce14d9105c
Reviewed-on: https://go-review.googlesource.com/c/go/+/210639
Trust: Emmanuel Odeke <emm.odeke@gmail.com>
Trust: Ian Lance Taylor <iant@golang.org>
Trust: Michael Pratt <mpratt@google.com>
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2020-10-23 20:53:14 +00:00
Russ Cox
7bb721b938 all: update references to symbols moved from os to io/fs
The old os references are still valid, but update our code
to reflect best practices and get used to the new locations.

Code compiled with the bootstrap toolchain
(cmd/asm, cmd/dist, cmd/compile, debug/elf)
must remain Go 1.4-compatible and is excluded.

For #41190.

Change-Id: I8f9526977867c10a221e2f392f78d7dec073f1bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/243907
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
2020-10-20 02:32:42 +00:00
Ian Lance Taylor
910fee4ed5 syscall: append to environment in tests, don't clobber it
Fixes https://gcc.gnu.org/PR95061

Change-Id: I3cddfe5920b6da572ddeafa201617003c25175e6
Reviewed-on: https://go-review.googlesource.com/c/go/+/233318
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2020-05-11 22:26:51 +00:00
Tobias Klauser
6e111956ab syscall: skip TestSyscallNoError on mips{,le}
On MIPS, Linux returns whether the syscall had an error in a separate
register (R7), not using a negative return value as on other
architectures. Thus, skip TestSyscallNoError as there is no error case
for syscall.RawSyscall which it could test against.

Also reformat the error output so the expected and gotten values are
aligned so they're easier to compare.

Fixes #35422

Change-Id: Ibc88f7c5382bb7ee8faf15ad4589ca1f9f017a06
Reviewed-on: https://go-review.googlesource.com/c/go/+/205898
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2019-11-09 19:25:46 +00:00
Brad Fitzpatrick
5fcc24074f syscall: skip TestSyscallNoError when temp dir is mounted nosuid
Fixes #30258

Change-Id: I73b63eb9d3aca00f562fdc3af010e96269bb6b9c
Reviewed-on: https://go-review.googlesource.com/c/162891
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Katie Hockman <katie@golang.org>
2019-02-15 19:24:37 +00:00
Tobias Klauser
5eec2373e4 syscall: enable TestSyscallNoError on all Linux 32-bit architectures
Check the size of uintptr instead of listing GOARCHes explicitly. This
will make the test also run on linux/mips{,le}.

Change-Id: I649f15d293002afc1360b1913910202c3e5188b7
Reviewed-on: https://go-review.googlesource.com/135715
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-09-17 16:22:04 +00:00
Ben Shi
c624f8ff70 syscall: skip TestSyscallNoError on rooted android/arm
The system call geteuid can not work properly on android, which
causes a test case failed on rooted android/arm.

This CL disables the test case on android.

Fixes #27364

Change-Id: Ibfd33ef8cc1dfe8822c8be4280eae12ee30929c1
Reviewed-on: https://go-review.googlesource.com/132175
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
2018-08-30 11:14:39 +00:00
Ian Lance Taylor
d970519086 syscall: support Faccessat flags argument
The Linux kernel faccessat system call does not take a flags parameter.
The flag parameter to the C library faccessat function is implemented in C.
The syscall.Faccessat function takes a flags parameter. In older releases
we have passed the flags parameter to the kernel, which ignored it.
In CL 120015 we started returning an error if any flags were set.
That seems clearly better than ignoring them, but it turns out that some
code was using the flags. The code was previously subtly broken.
Now it is obviously broken. That is better, but we can do better still:
we can implement the flags as the C library does. That is what this CL does.

Change-Id: I259bd6f240c3951e939b81c3032dead3d9c567b4
Reviewed-on: https://go-review.googlesource.com/126415
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-07-27 21:13:43 +00:00
Tobias Klauser
85e38cccb4 syscall: check faccessat flags parameter on Linux
Port CL 119495 from golang.org/x/sys/unix to the syscall package.

Currently Linux faccessat(2) syscall implementation doesn't support the
flags parameter. As per the discussion in #25845, permit the same flags
as glibc [1].

[1] https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/faccessat.c;h=ea42b2303ff4b2d2d6548ea04376fb265f773436;hb=HEAD

Updates #25845

Change-Id: I132b33275a9cc72b3a97acea5482806c7f47d7f7
Reviewed-on: https://go-review.googlesource.com/120015
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-06-21 06:47:46 +00:00
Tobias Klauser
fb4fb0430b syscall: check Fchmodat flags parameter on Linux
As mentioned in #25845, port CL 46474 from golang.org/x/sys/unix to the
syscall package.

Currently Linux' fchmodat(2) syscall implementation doesn't support the
flags parameter (though it might in future versions [1]). Fchmodat in
the syscall package takes the parameter and (wrongly) passes it on to the
syscall which will ignore it.

According to the POSIX.1-2008 manual page [2], AT_SYMLINK_NOFOLLOW is
the only valid value for the flags parameter and EOPNOTSUPP should be
returned in case changing the mode of a symbolic link is not supported
by the underlying system. EINVAL should be returned for any other value
of the flags parameter.

  [1] https://patchwork.kernel.org/patch/9596301/
  [2] http://pubs.opengroup.org/onlinepubs/9699919799/functions/chmod.html

Updates #20130
Updates #25845

Change-Id: I1021dd0e6a4f4cb3557cb1c1b34dd618c378cda6
Reviewed-on: https://go-review.googlesource.com/118658
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-06-13 20:32:08 +00:00
Tobias Klauser
495eb3f922 syscall: remove/update outdated TODO comments
Error returns for linux/arm syscalls are handled since a long time.

Remove another list of unimplemented syscalls, following CL 96315.

The root-only check in TestSyscallNoError was shown to be sufficient as
part of CL 84485 already.

NetBSD and OpenBSD do not implement the sendfile syscall (yet), so add a
link to golang.org/issue/5847

Change-Id: I07efc3c3203537a4142707385f31b59dc0ecca42
Reviewed-on: https://go-review.googlesource.com/97115
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-02-26 17:54:31 +00:00
Tobias Klauser
36951a9f63 syscall: support syscalls without error return on Linux
Add the rawSyscallNoError wrapper function which is used for Linux
syscalls that don't return an error and convert all applicable
occurences of RawSyscall to use it instead.

Fixes #22924

Change-Id: Iff1eddb54573d459faa01471f10398b3d38528dd
Reviewed-on: https://go-review.googlesource.com/84485
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-02-13 15:57:31 +00:00
David Stainton
6fd8c006ad syscall: add bounds checking and error returns to ParseNetlinkMessage
Fixes #16681

Change-Id: I6ff7ec81fe48ab06be3aae5b7ff92e9dc70960c3
Reviewed-on: https://go-review.googlesource.com/26990
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>
2016-09-14 08:42:28 +00:00
Alexander Morozov
d5e32ebf54 syscall: fix formatting calls in tests
Change-Id: I39a2c4101e6c59f4cd693cb0368f3567ea37ca5b
Reviewed-on: https://go-review.googlesource.com/14255
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-09-03 21:08:04 +00:00
Andrew Williams
9b379d7e04 syscall: relocate linux death signal code
Fix bug on Linux SysProcAttr handling: setting both Pdeathsig and
Credential caused Pdeathsig to be ignored. This is because the kernel
clears the deathsignal field when performing a setuid/setgid
system call.

Avoid this by moving Pdeathsig handling after Credential handling.

Fixes #9686

Change-Id: Id01896ad4e979b8c448e0061f00aa8762ca0ac94
Reviewed-on: https://go-review.googlesource.com/3290
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-05-12 19:34:46 +00:00