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625 Commits

Author SHA1 Message Date
Russ Cox 99950270f3 [release-branch.go1.16] syscall: avoid writing to p when Pipe(p) fails
Generally speaking Go functions make no guarantees
about what has happened to result parameters on error,
and Pipe is no exception: callers should avoid looking at
p if Pipe returns an error.

However, we had a bug in which ForkExec was using the
content of p after a failed Pipe, and others may too.
As a robustness fix, make Pipe avoid writing to p on failure.

Updates #50057

Change-Id: Ie8955025dbd20702fabadc9bbe1d1a5ac0f36305
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1291271
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/370515
Trust: Filippo Valsorda <filippo@golang.org>
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Alex Rakoczy <alex@golang.org>
2021-12-09 12:28:59 +00:00
Russ Cox 44a3fb49d9 [release-branch.go1.16] syscall: fix ForkLock spurious close(0) on pipe failure
Pipe (and therefore forkLockPipe) does not make any guarantees
about the state of p after a failed Pipe(p). Avoid that assumption
and the too-clever goto, so that we don't accidentally Close a real fd
if the failed pipe leaves p[0] or p[1] set >= 0.

Updates #50057
Fixes CVE-2021-44717

Change-Id: Iff8e19a6efbba0c73cc8b13ecfae381c87600bb4
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1291270
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/370514
Trust: Filippo Valsorda <filippo@golang.org>
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Alex Rakoczy <alex@golang.org>
2021-12-09 12:28:55 +00:00
Rahul Bajaj fd129a6b0e [release-branch.go1.16] syscall: fix TestGroupCleanupUserNamespace test failure on Fedora
For #46752
Fixes #46769

Change-Id: I2eaa9d15fac4e859e18191fcf1372e5be94899df
GitHub-Last-Rev: 8a2672d8dc
GitHub-Pull-Request: golang/go#46753
Reviewed-on: https://go-review.googlesource.com/c/go/+/328109
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
(cherry picked from commit a752bc0746)
Reviewed-on: https://go-review.googlesource.com/c/go/+/329831
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2021-06-21 22:46:57 +00:00
Jason A. Donenfeld 4fd2617cd8 [release-branch.go1.16] syscall: do not overflow key memory in GetQueuedCompletionStatus
The third argument to GetQueuedCompletionStatus is a pointer to a
uintptr, not a uint32. Users of this functions have therefore been
corrupting their memory every time they used it. Either that memory
corruption was silent (dangerous), or their programs didn't work so they
chose a different API to use.

This fixes the problem by passing through an intermediate buffer.

Updates #44538.
Fixes #44593.

Change-Id: Icacd71f705b36e41e52bd8c4d74898559a27522f
Reviewed-on: https://go-review.googlesource.com/c/go/+/296150
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-03-01 21:33:08 +00:00
Ian Lance Taylor b7e0eb49d8 [release-branch.go1.16] syscall: add explicit ios build tag
This permits analysis of the syscall package by tools built with
older versions of Go that do not recognize ios as a GOOS.

For #44459
Fixes #44462

Change-Id: I79cec2ffe0dbcbc2dc45a385e556dc9e62033125
Reviewed-on: https://go-review.googlesource.com/c/go/+/294634
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
(cherry picked from commit 03d36d8198)
Reviewed-on: https://go-review.googlesource.com/c/go/+/294635
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-02-25 22:48:20 +00:00
Ori Bernstein ed3e4afa12 syscall/plan9: remove spooky fd action at a distance
Change Plan 9 fork/exec to use the O_CLOEXEC file
descriptor, instead of relying on spooky at a
distance.

Historically, Plan 9 has set the O_CLOEXEC flag on
the underlying channels in the kernel, rather
than the file descriptors -- if two fds pointed
at a single channel, as with dup, changing the
flags on one of them would be observable on the
other.

The per-Chan semantics are ok, if unexpected,
when a chan is only handled within a single
process, but this isn't always the case.

Forked processes share Chans, but even more of
a problem is the interaction between /srv and
OCEXEC, which can lead to unexectedly closed
file descriptors in completely unrelated
proceses. For example:

	func exists() bool {
		// If some other thread execs here,
		// we don't want to leak the fd, so
		// open it O_CLOEXEC
		fd := Open("/srv/foo", O_CLOEXEC)
		if fd != -1 {
			Close(fd)
			return true
		}
		return false
	}

would close the connection to any file descriptor
(maybe even for the root fs) in ALL other processes
that have it open if an exec were to happen(!),
which is quite undesriable.

As a result, 9front will be changing this behavior
for the next release.

Go is the only code observed so far that relies on
this behavior on purpose, and  It's easy to make the
code work with both semantics: simply using the file
descriptor that was opened with O_CEXEC instead of
throwing it away.

So we do that here.

Fixes #43524

Change-Id: I4887f5c934a5e63e5e6c1bb59878a325abc928d3
GitHub-Last-Rev: 96bb21bd1e
GitHub-Pull-Request: golang/go#43533
Reviewed-on: https://go-review.googlesource.com/c/go/+/281833
Reviewed-by: David du Colombier <0intro@gmail.com>
Reviewed-by: Richard Miller <millerresearch@gmail.com>
Reviewed-by: Jacob Moody <j4kem00dy@gmail.com>
Run-TryBot: David du Colombier <0intro@gmail.com>
Trust: Ian Lance Taylor <iant@golang.org>
2021-02-08 15:56:59 +00:00
Joel Sing c8bd8010ff syscall: generate readlen/writelen for openbsd libc
Rather than hand rolling readlen and writelen, move it to being generated
via mksyscall.pl, as is done for most other functions.

Updates #36435

Change-Id: I649aed7b182b41c8639686feae25ce19dab812c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/287532
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-01-28 16:45:43 +00:00
Joel Sing 376518d77f runtime,syscall: convert syscall on openbsd/arm64 to libc
Convert the syscall package on openbsd/arm64 to use libc rather than performing
direct system calls.

Updates #36435

Change-Id: I7e1da8537cea9ed9bf2676f181e56ae99383333f
Reviewed-on: https://go-review.googlesource.com/c/go/+/286815
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-01-28 02:19:23 +00:00
Joel Sing 5cdf0da1bf syscall: clean up mkasm related changes
The mkasm_darwin.go file was renamed to mkasm.go in CL 270380, with OpenBSD
support being added. The mkasm_openbsd.go file should not have been merged,
so remove it. Fix up references to mkasm_$GOOS.go and provide $GOOS as an
argument on invocation.

Updates #36435

Change-Id: I868d3f2146973d026e6a663d437749dbb6b312ec
Reviewed-on: https://go-review.googlesource.com/c/go/+/286812
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-01-27 12:01:17 +00:00
Joel Sing 8634a234df runtime,syscall: convert syscall on openbsd/amd64 to libc
Convert the syscall package on openbsd/amd64 to use libc rather than performing
direct system calls.

Updates #36435

Change-Id: Ieb5926a91ed34f7c722e3667004ec484c86804ef
Reviewed-on: https://go-review.googlesource.com/c/go/+/270380
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-01-26 07:10:57 +00:00
Jason A. Donenfeld bb5075a525 syscall: remove RtlGenRandom and move it into internal/syscall
There's on need to expose this to the frozen syscall package, and it
also doesn't need to be unsafe. So we move it into internal/syscall and
have the generator make a safer function signature.

Fixes #43704.

Change-Id: Iccae69dc273a0aa97ee6846eb537f1dc1412f2de
Reviewed-on: https://go-review.googlesource.com/c/go/+/283992
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
2021-01-15 18:42:27 +00:00
Andrew G. Morgan b0b0d98283 runtime: linux iscgo support for not blocking nptl signals
Under linux+cgo, OS threads are launched via pthread_create().
This abstraction, under linux, requires we avoid blocking
signals 32,33 and 34 indefinitely because they are needed to
reliably execute POSIX-semantics threading in glibc and/or musl.

When blocking signals the go runtime generally re-enables them
quickly. However, when a thread exits (under cgo, this is
via a return from mstart()), we avoid a deadlock in C-code by
not blocking these three signals.

Fixes #42494

Change-Id: I02dfb2480a1f97d11679e0c4b132b51bddbe4c14
Reviewed-on: https://go-review.googlesource.com/c/go/+/269799
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Trust: Tobias Klauser <tobias.klauser@gmail.com>
2020-12-23 02:10:51 +00:00
Cherry Zhang bc7e4d9257 syscall: don't generate ptrace on iOS
May fix #43302.

Change-Id: I6b7ddf94495c4fa80cf8a50a38eef5f8b2872669
Reviewed-on: https://go-review.googlesource.com/c/go/+/279481
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-12-21 21:48:47 +00:00
Ian Lance Taylor e012d0dc34 syscall: drop references to Unix epoch in Timeval/Timespec docs
The various conversion functions just change the format of time values.
They don't use the Unix epoch. Although in practice the values are often
times since the Unix epoch, they aren't always, so referring to the
epoch can be confusing.

Fixes #43010

Change-Id: I640d665f0d2017f0974db05d70858037c7c91eda
Reviewed-on: https://go-review.googlesource.com/c/go/+/277073
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
2020-12-10 23:24:38 +00:00
Russ Cox 4f1b0a44cb all: update to use os.ReadFile, os.WriteFile, os.CreateTemp, os.MkdirTemp
As part of #42026, these helpers from io/ioutil were moved to os.
(ioutil.TempFile and TempDir became os.CreateTemp and MkdirTemp.)

Update the Go tree to use the preferred names.

As usual, code compiled with the Go 1.4 bootstrap toolchain
and code vendored from other sources is excluded.

ReadDir changes are in a separate CL, because they are not a
simple search and replace.

For #42026.

Change-Id: If318df0216d57e95ea0c4093b89f65e5b0ababb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/266365
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-12-09 19:12:23 +00:00
Jason A. Donenfeld be9379f8a8 syscall: correct CertOpenStore to expect a 0 return value on failure
According to [1], this function returns NULL when it errors, rather than
INVALID_HANDLE_VALUE, which other Win32 functions return. This was
pointed out in CL 273446 for the x/sys package, and this patch here
cleans it up for the syscall package and updates the vendored x/sys
package using the usual `go get/go mod vendor` dance. The function is
currently in use by crypto/x509/root_windows.go, which calls
CertOpenStore(CERT_STORE_PROV_MEMORY), which I assume can fail under OOM
or other weird conditions. Quick reversing indicates that [1] is
correct, as there's a `xor eax, eax` in the error paths of the function
just before jumping to the epilogue.

[1] https://docs.microsoft.com/en-us/windows/win32/api/wincrypt/nf-wincrypt-certopenstore#return-value

Change-Id: I77c0b0319c13313212f8710785252c494da56ed5
Reviewed-on: https://go-review.googlesource.com/c/go/+/273827
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Trust: Alex Brainman <alex.brainman@gmail.com>
2020-12-05 12:36:42 +00:00
Jason A. Donenfeld f7342596da syscall: add DLLError.Unwrap function
Because we're expecting for future functions to be unavailable, we
should add an Unwrap() function to the DLLError struct, so that people
can test for this situation easily via:

    if errors.Is(err, syscall.ERROR_PROC_NOT_FOUND) { ... }

DLLError already was wrapping the underlying Errno error, but never got
the Go 1.13 helper method.

Fixes golang/go#42584

Change-Id: I0f32a5146946b1b37a30897ba825a56faefc792c
Reviewed-on: https://go-review.googlesource.com/c/go/+/269761
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Trust: Alex Brainman <alex.brainman@gmail.com>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
2020-11-21 07:37:02 +00:00
Joel Sing 31f71506d7 syscall: use correct type for TIOCSPGRP/TIOCGPGRP
These ioctls take a pid_t (generally a C integer aka int32) and not an int64 - we
currently get away with this on little endian 64 bit platforms, since the bytes
fall into the correct place, however this breaks on big endian 64 bit platforms
(like openbsd/mips64).

Update #40995

Change-Id: I622a0543fd562d97f76a7376a84fd2641e6d6a24
Reviewed-on: https://go-review.googlesource.com/c/go/+/267605
Trust: Joel Sing <joel@sing.id.au>
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-11-13 13:56:34 +00:00
Andrew G. Morgan f2e58c6d42 syscall: improve TestSetuidEtc() /proc/ parsing against races
TestSetuidEtc() was failing sporadically on linux-ppc64. From the
three https://build.golang.org/ logs, it looked like the logged
errors could be associated with threads dying, but proc reads
were, in some way, racing with their demise.

Exploring ways to increase thread demise, revealed that races
of this type can happen on non-ppc64 systems, and that
os.IsNotExist(err) was not a sufficient error condition test
for a thread's status file disappearing. This change includes a
fix for that to.

The actual issue on linux-ppc64 appears to be tied to PID reaping
and reuse latency on whatever the build test environment is for
linux-ppc64-buildlet. I suspect this can happen on any linux
system, however, especially where the container has a limited PID
range.

The fix for this, limited to the test (the runtime syscall support
is unchanged), is to confirm that the Pid for the interrogated
thread's /proc/<TID>/status file confirms that it is still
associated with the test-process' PID.

linux-ppc64-buildlet:
  go/bin/go test syscall -run=TestSetuidEtc -count=10000
  ok      syscall 104.285s

Fixes #42462

Change-Id: I55c84ab8361003570a405fa52ffec4949bf91113
Reviewed-on: https://go-review.googlesource.com/c/go/+/268717
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Tobias Klauser <tobias.klauser@gmail.com>
2020-11-11 20:49:53 +00:00
Johan Knutzen 1e3b535b6e syscall: expose bInheritHandles of CreateProcess
Certain use cases require this parameter to be false. This includes
spawning a child process in a different windows session than session 0.

Docs regarding the behavior of this parameter to CreateProcess:
https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-createprocessa

Fixes #42098

Change-Id: If998f57d6f2962824aacbee75e1b508b255ab293
GitHub-Last-Rev: 584eb13e36
GitHub-Pull-Request: golang/go#41957
Reviewed-on: https://go-review.googlesource.com/c/go/+/261917
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Trust: Alex Brainman <alex.brainman@gmail.com>
2020-11-05 02:28:14 +00:00
Bryan C. Mills 33d9251530 all: update dependency on golang.org/x/sys and regenerate Windows syscalls
Steps run:

	$ cd $(go env GOROOT)/src
	$ go get -d golang.org/x/sys
	$ go mod tidy
	$ go mod vendor
	$ go generate syscall/... internal/syscall/...
	$ cd cmd
	$ go get -d golang.org/x/sys
	$ go mod tidy
	$ go mod vendor
	$ cd ..
	$ git add .

This change subsumes CL 260860.

For #36905

Change-Id: I7c677c6aa1ad61b9cbd8cf9ed208ed5a30f29c87
Reviewed-on: https://go-review.googlesource.com/c/go/+/267103
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
2020-11-02 15:41:00 +00:00
Bryan C. Mills cb65c8d58a syscall: switch go:generate directives back to mksyscall_windows.go
Adjust mksyscall_windows.go to activate module mode and set
-mod=readonly, and to suppress its own deprecation warning when run
from within GOROOT/src.

We can't vendor the mkwinsyscall tool in to the std module directly,
because std-vendored dependencies (unlike the dependencies of all
other modules) turn into actual, distinct packages in 'std' when
viewed from outside the 'std' module. We don't want to introduce a
binary in the 'std' meta-pattern, but we also don't particularly want
to add more special-cases to the 'go' command right now when we have
an existing wrapper program that can do the job.

I also regenerated the affected packages to ensure that they are
consistent with the current version of mksyscall, which produced some
declaration-order changes in
internal/syscall/windows/zsyscall_windows.go.

Fixes #41916
Updates #25922

Change-Id: If6e6f8ba3dd372a7ecd6820ee6c0ca38d55f0f35
Reviewed-on: https://go-review.googlesource.com/c/go/+/261499
Trust: Bryan C. Mills <bcmills@google.com>
Trust: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
2020-11-02 15:31:49 +00:00
Andrew G. Morgan 3a819e8998 syscall: handle undefined r2 value on linux-ppc64x
This change fixes two failng tests on linux-ppc64x:

- TestAllThreadsSyscall() exposed a real bug in the ppc64x support:
  - It turns out that the r2 syscall return value is not defined
    on all architectures. Notably linux-ppc64x so address that by
    introducing a private architectural constant in the syscall
    package, archHonorsR2: true if r2 has a determanistic value.

- TestSetuidEtc() was sensitive to /proc/<PID>/status content:
  - The amount of padding space has changed with kernel vintage.
  - Stress testing revealed a race with /proc files disappearing.

Fixes #42178

Change-Id: Ie6fc0b8f2f94a409ac0e5756e73bfce113274709
Reviewed-on: https://go-review.googlesource.com/c/go/+/266202
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
2020-10-29 17:53:57 +00:00
Joel Sing d9725f549f syscall: add support for openbsd/mips64
Update #40995

Change-Id: I7afa520ab5ddd6d1b8c7960f400b7b3a1b67d976
Reviewed-on: https://go-review.googlesource.com/c/go/+/250581
Trust: Joel Sing <joel@sing.id.au>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
2020-10-29 08:08:26 +00:00
Jason A. Donenfeld 333e90448a crypto/rand: generate random numbers using RtlGenRandom on Windows
CryptGenRandom appears to be unfavorable these days, whereas the classic
RtlGenRandom is still going strong.

This commit also moves the warnBlocked function into rand_unix, rather
than rand, because it's now only used on unix.

Fixes #33542

Change-Id: I5c02a5917572f54079d627972401efb6e1ce4057
Reviewed-on: https://go-review.googlesource.com/c/go/+/210057
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
2020-10-27 12:00:35 +00:00
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>
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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 1b09d43067 all: update references to symbols moved from io/ioutil to io
The old ioutil 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.
Also excluded vendored code.

For #41190.

Change-Id: I6d86f2bf7bc37a9d904b6cee3fe0c7af6d94d5b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/263142
Trust: Russ Cox <rsc@golang.org>
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Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
2020-10-20 18:41:18 +00:00
Tobias Klauser 310984bf54 syscall, cmd/go/internal/modload: add and use Access on aix
Implement Access using Faccessat on aix following golang.org/x/sys/unix
CL 262897 and switch cmd/go/internal/modload to use it to implement
hasWritePerm.

Change-Id: I682e44737ac2bac5a203ac1c9ddd277810454426
Reviewed-on: https://go-review.googlesource.com/c/go/+/263540
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2020-10-20 07:33:13 +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>
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2020-10-20 02:32:42 +00:00
Ian Lance Taylor 11cfb48df1 syscall: use MustHaveExec in TestExec
For #41702

Change-Id: Ib2b15e52aa1fef2f5e644b316c726150252fa9f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/262738
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2020-10-17 00:32:32 +00:00
Tobias Klauser 9cec50f50c internal/poll, net, syscall: use accept4 on illumos
Illumos supports the accept4 syscall, use it in internal/poll.accept
like on other platforms.

Add Accept4 to package syscall despite the package being frozen. The
other option would have been to add this to internal/syscall/unix, but
adding it to syscall avoids duplicating a lot of code in internal/poll
and net/internal/socktest. Also, all other platforms supporting the
accept4 syscall already export Accept4.

Follow CL 97196, CL 40895 and CL 94295

Change-Id: I13b32f0163a683840c02b16722730d9dfdb98f56
Reviewed-on: https://go-review.googlesource.com/c/go/+/256101
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2020-10-16 19:53:34 +00:00
Ian Lance Taylor 64fb6ae95f runtime: stop preemption during syscall.Exec on Darwin
On current macOS versions a program that receives a signal during an
execve can fail with a SIGILL signal. This appears to be a macOS
kernel bug. It has been reported to Apple.

This CL partially works around the problem by using execLock to not
send preemption signals during execve. Of course some other stray
signal could occur, but at least we can avoid exacerbating the problem.
We can't simply disable signals, as that would mean that the exec'ed
process would start with all signals blocked, which it likely does not
expect.

Fixes #41702

Change-Id: I91b0add967b315671ddcf73269c4d30136e579b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/262438
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2020-10-15 18:30:07 +00:00
Tobias Klauser fc3a6f4533 syscall: remove stray TODO comment
This was addressed by CL 2816 and the same comment was deleted from
asm_linux_386.s.

Change-Id: Icc797993161d67e7c4f4cdb11c2b96ac88e00dd9
Reviewed-on: https://go-review.googlesource.com/c/go/+/261458
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2020-10-14 08:05:58 +00:00
Russ Cox 84f3b33f10 syscall: remove dependency on io
Keep syscall and io separated; neither should depend on the other.

Change-Id: Icdd61bd0c05d874cabd7b5ae6631dd09dec90112
Reviewed-on: https://go-review.googlesource.com/c/go/+/243902
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2020-10-13 00:55:35 +00:00
Cherry Zhang 23e9e0c7f0 syscall: support ptrace on macOS/ARM64
Updates #38485.

Change-Id: I853966d934a8ee05cf62c7321f3e6271811d47b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/260718
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2020-10-08 23:14:40 +00:00
Ian Lance Taylor 9e0837f2e9 syscall: restore EscapeArg behavior for empty string
Accidentally broken by CL 259978.

For #41825

Change-Id: Id663514e6eefa325faccdb66493d0bb2b3281046
Reviewed-on: https://go-review.googlesource.com/c/go/+/260397
Trust: Ian Lance Taylor <iant@golang.org>
Trust: Alex Brainman <alex.brainman@gmail.com>
Trust: Emmanuel Odeke <emm.odeke@gmail.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2020-10-08 20:46:25 +00:00
Ian Lance Taylor 4922585497 syscall: rewrite Windows makeCmdLine to use []byte
It's faster to append to a []byte and only convert to string at the
end then it is to build up a string by concatenating characters.

Fixes #41825

Change-Id: I45ddf77dcc62726c919f0533c95d483cee8ba366
Reviewed-on: https://go-review.googlesource.com/c/go/+/259978
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2020-10-07 16:33:31 +00:00
Cherry Zhang db428ad7b6 all: enable more tests on macOS/ARM64
Updates #38485.

Change-Id: Iac96f5ffe88521fcb11eab306d0df6463bdce046
Reviewed-on: https://go-review.googlesource.com/c/go/+/256920
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-10-06 21:56:24 +00:00
Tobias Klauser 069aef4067 syscall: use correct cmsg alignment for netbsd/arm64
netbsd/arm64 requires 128-bit alignment for cmsgs.

Re-submit of CL 258437 which was dropped due to #41718.

Change-Id: I898043d79f513bebe1a5eb931e7ebd8e291a5aec
Reviewed-on: https://go-review.googlesource.com/c/go/+/258677
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Trust: Benny Siegert <bsiegert@gmail.com>
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2020-10-01 13:23:43 +00:00
Andrei Vagin 3caaaddffd runtime: don't crash if vsyscall and vdso are disabled on x86_64
If vdso is disabled, the goruntime calls gettimeofday from vsyscall,
but if vsyscall is disabled too, all golang binaries crash:

SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0xffffffffff600000} ---
killed by SIGSEGV (core dumped) ++

vsyscall doesn't work as it was designed for a long time due to security
reasons and now vsyscall is a little more expensive than real syscalls:
https://github.com/torvalds/linux/commit/5cec93c216db

This patch reworks the code to call syscalls if the vdso library isn't
available.

Change-Id: I16cbf3f49871bea91e26af1f49aa0ae2fbd3a01d
GitHub-Last-Rev: 1d133cd30a
GitHub-Pull-Request: golang/go#41681
Reviewed-on: https://go-review.googlesource.com/c/go/+/257982
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2020-09-30 05:39:59 +00:00
Tobias Klauser 7d3fd4f3c4 syscall: implement Getwd using getcwd from libSystem on darwin
Directly wrap the getcwd implementation provided by libSystem.dylib on
darwin and use it to implement Getwd like on the BSDs. This allows to
drop the custom implementation using getAttrList and to merge the
implementation of Getwd for darwin and the BSDs in syscall_bsd.go.

Same as CL 257497 did for golang.org/x/sys/unix

Change-Id: If30390c4c17cd463bb8fdcb5465f40d6fa11f391
Reviewed-on: https://go-review.googlesource.com/c/go/+/257637
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2020-09-26 10:09:33 +00:00
Tobias Klauser dbb1c5bf74 syscall: remove mksysnum_darwin.pl script
Direct syscalls using syscall numbers are no longer supported on darwin
since Go 1.12, see https://golang.org/doc/go1.12#darwin. Also,
/usr/include/sys/syscall.h is no longer available on recent macOS
versions, so remove the generating script.

Change-Id: I8e2579c3d0e94a61fc041d06280149ec6ccf13e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/257638
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2020-09-26 10:08:43 +00:00
Cherry Zhang a413908dd0 all: add GOOS=ios
Introduce GOOS=ios for iOS systems. GOOS=ios matches "darwin"
build tag, like GOOS=android matches "linux" and GOOS=illumos
matches "solaris". Only ios/arm64 is supported (ios/amd64 is
not).

GOOS=ios and GOOS=darwin remain essentially the same at this
point. They will diverge at later time, to differentiate macOS
and iOS.

Uses of GOOS=="darwin" are changed to (GOOS=="darwin" || GOOS=="ios"),
except if it clearly means macOS (e.g. GOOS=="darwin" && GOARCH=="amd64"),
it remains GOOS=="darwin".

Updates #38485.

Change-Id: I4faacdc1008f42434599efb3c3ad90763a83b67c
Reviewed-on: https://go-review.googlesource.com/c/go/+/254740
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2020-09-23 18:12:59 +00:00
Tobias Klauser d140c35744 syscall: use libc-based ioctl for Ioctl in tests on darwin
Direct syscalls are no longer supported on darwin, instead wrap the
existing func ioctl for tests.

Change-Id: Ie2c5b6e5f54e992f4d6b21513ca8f89fcf28ef10
Reviewed-on: https://go-review.googlesource.com/c/go/+/256219
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-09-22 18:05:58 +00:00
Tobias Klauser 7f24142b7b syscall, cmd/go/internal/lockedfile/internal/filelock: add and use Flock on illumos
Copy the syscall wrapper from golang.org/x/sys/unix CL 255377 to provide
Flock on illumos and switch cmd/go/internal/lockedfile/internal/filelock
to use it.

Fixes #35618

Change-Id: I876a2b782329a988fa85361fb1ea58eb6f329af1
Reviewed-on: https://go-review.googlesource.com/c/go/+/255258
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2020-09-17 06:20:06 +00:00
Clément Chigot 86dbeefe1f syscall: fix fsync for read-only files on aix
AIX fsync syscall doesn't work on read-only files. Using fsync_range
instead allows syscall.Fsync to work on any files.

Fixes #41372

Change-Id: I66d33e847875496af53da60828c1bddf6c2b76b7
Reviewed-on: https://go-review.googlesource.com/c/go/+/254657
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2020-09-14 17:07:47 +00:00
Cholerae Hu bf512685fe syscall: cap RLIMIT_NOFILE soft limit in TestRlimit on darwin
On some machines, kern.maxfilesperproc is 4096. If Rlimit.Cur is larger
than that, Setrlimit will get an errEINVAL.

Fixes #40564.

Change-Id: Ib94303c790a489ff0559c88d41a021e514d18f8d
Reviewed-on: https://go-review.googlesource.com/c/go/+/246658
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2020-08-17 09:14:51 +00:00
Joel Sing d303630622 syscall: support rawVforkSyscall on linux/riscv64
Updates #31936

Change-Id: I7dcb8987d4c306ccc97704b9c1b12313ba8bf242
Reviewed-on: https://go-review.googlesource.com/c/go/+/234960
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2020-08-16 14:23:50 +00:00
Ian Lance Taylor 8696ae82c9 syscall: use correct file descriptor in dup2 fallback path
This fixes a mistake in CL 220422. This changes code that is only
executed on Linux kernel versions earlier than 2.6.27.

Change-Id: I01280184f4d7b75e06387c38f1891e8f0a81f793
Reviewed-on: https://go-review.googlesource.com/c/go/+/244630
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2020-07-25 20:13:27 +00:00