Commit Graph

600 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>
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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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Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
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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Reviewed-by: Rob Pike <r@golang.org>
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
Trust: Ian Lance Taylor <iant@golang.org>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
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
Trust: Ian Lance Taylor <iant@golang.org>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
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>
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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
Trust: Ian Lance Taylor <iant@golang.org>
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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
Run-TryBot: Ian Lance Taylor <iant@golang.org>
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2020-07-25 20:13:27 +00:00
Tobias Klauser 60f7876502 syscall: check secondary group membership for Faccessat(..., AT_EACCESS) on Linux
Follow glibc's implementation and check secondary group memberships
using Getgroups.

No test since we cannot easily change file permissions when not running
as root and the test is meaningless if running as root.

Same as CL 238722 did for x/sys/unix

Updates #39660

Change-Id: I6af50e27b255e33405558947a0ab3dfbc33b2d50
Reviewed-on: https://go-review.googlesource.com/c/go/+/238937
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2020-06-20 08:40:13 +00:00
Richard Miller af09ff1981 runtime, syscall: use local cache for Setenv/Getenv in Plan 9
In os.Getenv and os.Setenv, instead of directly reading and writing the
Plan 9 environment device (which may be shared with other processes),
use a local copy of environment variables cached at the start of
execution. This gives the same semantics for Getenv and Setenv as on
other operating systems which don't share the environment, making it
more likely that Go programs (for example the build tests) will be
portable to Plan 9.

This doesn't preclude writing non-portable Plan 9 Go programs which make
use of the shared environment semantics (for example to have a command
which exports variable definitions to the parent shell). To do this, use
  ioutil.ReadFile("/env/"+key) and
  ioutil.WriteFile("/env/"+key, value, 0666)
in place of os.Getenv(key) and os.Setenv(key, value) respectively.

Note that CL 5599054 previously added env cacheing, citing efficiency
as the reason. However it made the cache write-through, with Setenv
changing the shared environment as well as the cache (so not consistent
with Posix semantics), and Clearenv breaking the sharing of the
environment between the calling thread and other threads (leading to
unpredictable behaviour). Because of these inconsistencies (#8849),
CL 158970045 removed the cacheing again.

This CL restores cacheing but without write-through. The local cache is
initialised at start of execution, manipulated by the standard functions
in syscall/env_unix.go to ensure the same semantics, and exported only
when exec'ing a new program.

Fixes #34971
Fixes #25234
Fixes #19388
Updates #38772

Change-Id: I2dd15516d27414afaf99ea382f0e00be37a570c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/236520
Run-TryBot: David du Colombier <0intro@gmail.com>
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2020-06-19 11:28:19 +00:00
Austin Clements 07ced37013 syscall: document float arguments and results on windows/amd64
Updates #6510.
Updates #37273.

Change-Id: Id2732fcff0a0c5e4a324cd33ef995c7e528f5e1a
Reviewed-on: https://go-review.googlesource.com/c/go/+/236562
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2020-06-04 17:50:16 +00:00
Austin Clements 7e47757324 syscall: hide internal comment from Syscall documentation
There's a comment on the Syscall function that's supposed to be an
internal implementation note, but since it's not separated from the
function definition, it appears in godoc. Add a blank line to prevent
this.

Change-Id: Iba307f1cc3844689ec3c6d82c21d441852e35bca
Reviewed-on: https://go-review.googlesource.com/c/go/+/236561
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2020-06-04 17:50:15 +00:00
Elias Naur 2711127974 syscall: avoid dup2 in forkAndExecInChild1 on Android
Android O and newer blocks the dup2 syscall.

Change-Id: Ibca01fc72ef114deeef6c0450a8b81a556ed0530
Reviewed-on: https://go-review.googlesource.com/c/go/+/235537
Run-TryBot: Elias Naur <mail@eliasnaur.com>
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2020-05-28 19:51:59 +00:00
Joel Sing 20160b37c6 runtime, syscall: correct openbsd/arm and openbsd/arm64 syscalls for OpenBSD 6.7
Add two no op instructions following svc on openbsd/arm64 and swi on openbsd/arm.

All except some of the most recent arm64 processors have a speculative execution
flaw that occurs across a syscall boundary, which cannot be mitigated in the
kernel. In order to protect against this leak a speculation barrier needs to be
placed after an svc or swi instruction.

In order to avoid the performance impact of these instructions, the OpenBSD 6.7
kernel returns execution two instructions past the svc or swi call. For now two
hardware no ops are added, which allows syscalls to work with both 6.6 and 6.7.
These should be replaced with real speculation barriers once OpenBSD 6.8 is
released.

Updates #36435

Change-Id: I06153cb0998199242cca8761450e53599c3e7de4
Reviewed-on: https://go-review.googlesource.com/c/go/+/234381
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2020-05-26 17:02:46 +00:00
Richard Musiol 828bb0c123 syscall/js: improve documentation of Func.Release
Fixes #38152

Change-Id: I807f49e23cc33e1c9b64029c7504b5a1f81a6bab
Reviewed-on: https://go-review.googlesource.com/c/go/+/235138
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
2020-05-24 17:46:52 +00:00
Ian Lance Taylor 567556d786 syscall: preserve Windows file permissions for O_CREAT|O_TRUNC
On Windows, calling syscall.Open(file, O_CREAT|O_TRUNC, 0) for a file
that already exists would change the file to be read-only.
That is not how the Unix syscall.Open behaves, so avoid it on
Windows by calling CreateFile twice if necessary.

Fixes #38225

Change-Id: I70097fca8863df427cc8a97b9376a9ffc69c6318
Reviewed-on: https://go-review.googlesource.com/c/go/+/234534
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
2020-05-20 21:52:34 +00:00
Hajime Hoshi a0698a6b60 syscall/js: prepare IDs for the preset objects
Fixes #38899

Change-Id: Ib8131c3078c60dc3fe2cf0eaac45b25a4f6e4649
Reviewed-on: https://go-review.googlesource.com/c/go/+/232518
Run-TryBot: Hajime Hoshi <hajimehoshi@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
2020-05-12 15:01:56 +00:00
Ian Lance Taylor 8c1db77a92 internal/poll, os: loop on EINTR
Historically we've assumed that we can install all signal handlers
with the SA_RESTART flag set, and let the system restart slow functions
if a signal is received. Therefore, we don't have to worry about EINTR.

This is only partially true, and we've added EINTR checks already for
connect, and open/read on Darwin, and sendfile on Solaris.

Other cases have turned up in #36644, #38033, and #38836.

Also, #20400 points out that when Go code is included in a C program,
the C program may install its own signal handlers without SA_RESTART.
In that case, Go code will see EINTR no matter what it does.

So, go ahead and check for EINTR. We don't check in the syscall package;
people using syscalls directly may want to check for EINTR themselves.
But we do check for EINTR in the higher level APIs in os and net,
and retry the system call if we see it.

This change looks safe, but of course we may be missing some cases
where we need to check for EINTR. As such cases turn up, we can add
tests to runtime/testdata/testprogcgo/eintr.go, and fix the code.
If there are any such cases, their handling after this change will be
no worse than it is today.

For #22838
Fixes #20400
Fixes #36644
Fixes #38033
Fixes #38836

Change-Id: I7e46ca8cafed0429c7a2386cc9edc9d9d47a6896
Reviewed-on: https://go-review.googlesource.com/c/go/+/232862
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2020-05-11 22:38:32 +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
Alex Brainman 53f27474a4 syscall, internal/syscall/windows: remove utf16PtrToString parameter
CL 208617 introduced syscall.utf16PtrToString and
internal/syscall/windows.UTF16PtrToString functions.

Original version of CL 208617 did not include syscall.utf16PtrToString
and internal/syscall/windows.UTF16PtrToString max parameter. The
parameter was added by Brad at the request of Ian. Ian said:

"In some cases it seems at least possible that the null terminator is
not present. I think it would be safer if we passed a maximum length
here."

The syscall.utf16PtrToString and
internal/syscall/windows.UTF16PtrToString function are designed to work
with only null terminated strings. So max parameter is superfluous.

This change removes max parameter.

Updates #34972

Change-Id: Ifea65dbd86bca8a08353579c6b9636c6f963d165
Reviewed-on: https://go-review.googlesource.com/c/go/+/228858
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2020-05-03 07:23:32 +00:00
Ian Lance Taylor be08e10b3b syscall: if Setctty, require that Ctty be a child descriptor
Ctty was always handled as a child descriptor, but in some cases
passing a parent descriptor would also work. This depended on
unpredictable details of the implementation. Reject those cases to
avoid confusion.

Also reject setting both Setctty and Foreground, as they use Ctty
in incompatible ways. It's unlikely that any programs set both fields,
as they don't make sense together.

Fixes #29458

Change-Id: Ieba2d625711fd4b82c8e65e1feed02fd1fb25e6d
Reviewed-on: https://go-review.googlesource.com/c/go/+/231638
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
2020-05-01 21:57:29 +00:00
Ian Lance Taylor 07cb63aae5 syscall: document exact meaning of Ctty field
The Ctty field is a child descriptor number when Setctty is set,
but a parent descriptor when Foreground is set. This is absurd
but changing either behavior breaks existing programs.

With this change we at least document how it works.

For #29458

Change-Id: If9cf0a1a1e6ed0d4a4edae5043016d5b4ee3308b
Reviewed-on: https://go-review.googlesource.com/c/go/+/229768
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
2020-05-01 04:53:11 +00:00
Bryan C. Mills da382a3978 internal/unsafeheader: consolidate stringHeader and sliceHeader declarations into an internal package
The new package "internal/unsafeheader" depends only on "unsafe", and
provides declarations equivalent to reflect.StringHeader and
reflect.SliceHeader but with Data fields of the proper unsafe.Pointer
type (instead of uintptr).

Unlike the types it replaces, the "internal/unsafeheader" package has
a regression test to ensure that its header types remain equivalent to
the declarations provided by the "reflect" package.

Since "internal/unsafeheader" has almost no dependencies, it can be
used in other low-level packages such as "syscall" and "reflect".

This change is based on the corresponding x/sys change in CL 231177.

Fixes #37805
Updates #19367

Change-Id: I7a6d93ef8dd6e235bcab94e7c47270aad047af31
Reviewed-on: https://go-review.googlesource.com/c/go/+/231223
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-05-01 02:31:29 +00:00
Ian Lance Taylor b255c12337 syscall: on linux-arm64, prefer prlimit to {g,s}etrlimit
Reportedly some Docker images accept the prlimit64 system call,
used by syscall.prlimit, but prohibit the getrlimit and setrlimit
system calls.

Fixes #38604

Change-Id: I91ff9370450b4869098cc8e335bbb7b863060508
Reviewed-on: https://go-review.googlesource.com/c/go/+/230339
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
2020-04-30 03:32:25 +00:00
Austin Clements d5e1b7ca68 all: remove scattered remnants of darwin/386
This removes all conditions and conditional code (that I could find)
that depended on darwin/386.

Fixes #37610.

Change-Id: I630d9ea13613fb7c0bcdb981e8367facff250ba0
Reviewed-on: https://go-review.googlesource.com/c/go/+/227582
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-04-08 18:37:38 +00:00
Austin Clements 8b4cbcc320 all: remove darwin/386 build-tags and files
This removes all files that are only used on darwin/386 and cleans up
build tags in files that are still used on other platforms.

Updates #37610.

Change-Id: If246642476c12d15f59a474e2b91a29c0c02fe75
Reviewed-on: https://go-review.googlesource.com/c/go/+/227581
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-04-08 18:37:36 +00:00
Austin Clements f7e6ab44b4 all: remove scattered remnants of darwin/arm
This removes all conditions and conditional code (that I could find)
that depended on darwin/arm.

Fixes #35439 (since that only happened on darwin/arm)
Fixes #37611.

Change-Id: Ia4c32a5a4368ed75231075832b0b5bfb1ad11986
Reviewed-on: https://go-review.googlesource.com/c/go/+/227198
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-04-08 18:35:49 +00:00
Austin Clements da8591b61c all: remove darwin/arm build-tags and files
This removes all files that are only used on darwin/arm and cleans up
build tags in files that are still used on other platforms.

Updates #37611.

Change-Id: Ic9490cf0edfc157c6276a7ca950c1768b34a998f
Reviewed-on: https://go-review.googlesource.com/c/go/+/227197
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-04-08 18:35:43 +00:00
Alex Brainman 9667294d8f syscall: fix windows WSASendto -d=checkptr violation
WSASendto converts unsafe.Pointer to *syscall.RawSockaddrAny. But that
violates every rule of

https://golang.org/pkg/unsafe/#Pointer

Implement WSASendto by calling Windows WSASendTo API by calling
syscall.Syscall9 directly. This allows us to comply with

(4) Conversion of a Pointer to a uintptr when calling syscall.Syscall

rule.

After this change, this commands succeeds:

go test -a -short -gcflags=all=-d=checkptr -run=TestPacketConn net

Updates #34972

Change-Id: Ib9a810bedf9e05251b7d3c7f69e15bfbd177ac62
Reviewed-on: https://go-review.googlesource.com/c/go/+/220544
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-04-02 09:00:34 +00:00
Aurélio A. Heckert f0e8b81aa3 syscall/js: allow copyBytesTo(Go|JS) to use Uint8ClampedArray
closes #38011

Change-Id: Ic50f2f27456dccdc3fca1bda076871af1eb81705
Reviewed-on: https://go-review.googlesource.com/c/go/+/224638
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Richard Musiol <neelance@gmail.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-03-24 10:31:12 +00:00
Torben Schinke a4f7b0879c syscall/js: improve documentation of js.FuncOf
The existing documentation is improved to be more
explicit about the lifecycle and its consequences.

Fixes #34324

Change-Id: I9969afc69f6eeb7812c11fe821a842794df5aa5b
GitHub-Last-Rev: 246a499166
GitHub-Pull-Request: golang/go#34551
Reviewed-on: https://go-review.googlesource.com/c/go/+/197458
Reviewed-by: Richard Musiol <neelance@gmail.com>
2020-03-01 21:04:30 +00:00
Richard Musiol e44cda3aa9 syscall: fix Fchdir on js/wasm
NodeJS does not support fchdir so it has to be emulated with chdir by
saving the path when opening a directory.

However, if the path opened is relative, saving this path is not
sufficient, because after changing the working directory the path
does not resolve correctly any more, thus a subsequent fd.Chdir() fails.

This change fixes the issue by resolving a relative path when
opening the directory and saving the absolute path instead.

Fixes #37448

Change-Id: Id6bc8c4232b0019fc11e850599a526336608ce54
Reviewed-on: https://go-review.googlesource.com/c/go/+/221717
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
2020-03-01 21:02:40 +00:00
Tobias Klauser 31acdcc701 syscall: use dup3 in forkAndExecInChild1 if available
The dup3 syscall is available since Linux 2.6.27. Fall back to dup2 (if
available) if dup3 returns ENOSYS.

This allows to omit the additional fcntl call to mark the dup'ed fd as
close-on-exec.

Change-Id: If318b593edd783f2aa988534c6062498e7119ddb
Reviewed-on: https://go-review.googlesource.com/c/go/+/220422
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-02-24 08:31:48 +00:00