Commit Graph

27 Commits

Author SHA1 Message Date
Bryan C. Mills 07ede7a543 syscall: serialize locks on ForkLock on platforms where forkExecPipe is not atomic
In CL 421441, we changed syscall to allow concurrent calls to
forkExec.

On platforms that support the pipe2 syscall that is the right
behavior, because pipe2 atomically opens the pipe with CLOEXEC already
set.

However, on platforms that do not support pipe2 (currently aix and
darwin), syscall.forkExecPipe is not atomic, and the pipes do not
initially have CLOEXEC set. If two calls to forkExec proceed
concurrently, a pipe intended for one child process can be
accidentally inherited by the other. If the process is long-lived, the
pipe can be held open unexpectedly and prevent the parent process from
reaching EOF reading the child's status from the pipe.

Fixes #61080.
Updates #23558.
Updates #54162.

Change-Id: I83edcc80674ff267a39d06260c5697c654ff5a4b
Reviewed-on: https://go-review.googlesource.com/c/go/+/507355
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Bryan Mills <bcmills@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
2023-07-10 19:19:59 +00:00
Roland Shoemaker 96b79bd320 syscall: don't panic when argv is nil on freebsd
The workaround in CL 69970044 introduced a panic when StartProcess is
called with empty argv. Check the length before trying to access it.

Change-Id: Ic948d86c7067a21c484ba24e100d1f1f80179730
Reviewed-on: https://go-review.googlesource.com/c/go/+/500415
Run-TryBot: Roland Shoemaker <roland@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2023-06-05 15:22:32 +00:00
Ian Lance Taylor d6473a1263 syscall: avoid serializing forks on ForkLock
Fixes #23558
Fixes #54162

Change-Id: I3cf6efe466080cdb17e171218e9385ccb272c301
Reviewed-on: https://go-review.googlesource.com/c/go/+/421441
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
2023-05-23 17:25:09 +00:00
Ian Lance Taylor f5eef58e43 syscall: restore original NOFILE rlimit in child process
If we increased the NOFILE rlimit when starting the program,
restore the original rlimit when forking a child process.

For #46279

Change-Id: Ia5d2af9ef435e5932965c15eec2e428d2130d230
Reviewed-on: https://go-review.googlesource.com/c/go/+/476097
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Bypass: Ian Lance Taylor <iant@google.com>
2023-03-15 17:21:30 +00:00
Ian Lance Taylor a2baae6851 all: use new "unix" build tag where appropriate
For #20322
For #51572

Change-Id: Id0b4799d097d01128e98ba4cc0092298357bca45
Reviewed-on: https://go-review.googlesource.com/c/go/+/389935
Trust: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
2022-03-29 16:24:51 +00:00
Russ Cox a76511f3a4 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.

Fixes #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/+/370576
Run-TryBot: Filippo Valsorda <filippo@golang.org>
Trust: Russ Cox <rsc@golang.org>
Reviewed-by: Alex Rakoczy <alex@golang.org>
2021-12-09 13:36:16 +00:00
Russ Cox f229e7031a all: go fix -fix=buildtag std cmd (except for bootstrap deps, vendor)
When these packages are released as part of Go 1.18,
Go 1.16 will no longer be supported, so we can remove
the +build tags in these files.

Ran go fix -fix=buildtag std cmd and then reverted the bootstrapDirs
as defined in src/cmd/dist/buildtool.go, which need to continue
to build with Go 1.4 for now.

Also reverted src/vendor and src/cmd/vendor, which will need
to be updated in their own repos first.

Manual changes in runtime/pprof/mprof_test.go to adjust line numbers.

For #41184.

Change-Id: Ic0f93f7091295b6abc76ed5cd6e6746e1280861e
Reviewed-on: https://go-review.googlesource.com/c/go/+/344955
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2021-10-28 18:17:57 +00:00
Joel Sing bedf2c4886 runtime,syscall: convert syscall on openbsd/arm to libc
Convert the syscall package on openbsd/arm to use libc rather than performing
direct system calls.

Updates #36435

Change-Id: Iff3a91c959292cbf4e0a09c7fd34efc8e88ff83f
Reviewed-on: https://go-review.googlesource.com/c/go/+/315793
Trust: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
2021-05-09 17:07:01 +00:00
Joel Sing 8e91458b19 runtime,syscall: convert syscall on openbsd/386 to libc
Convert the syscall package on openbsd/386 to use libc rather than performing
direct system calls.

Updates #36435

Change-Id: Ifcfbca0e6b933762596a564243caa850dac01442
Reviewed-on: https://go-review.googlesource.com/c/go/+/287654
Trust: Joel Sing <joel@sing.id.au>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-04-30 20:00:36 +00:00
Tobias Klauser f9e2dbbfc9 syscall: use libc in Exec on openbsd/arm64
Like on openbsd/amd64, use libc instead of direct syscalls on
openbsd/arm64.

This was likely missed in CL 286815. A similar change was done for
openbsd/amd64 in CL 270380.

Updates #36435

Change-Id: Ie496a6130f1a43d30974502777db12217e65c551
Reviewed-on: https://go-review.googlesource.com/c/go/+/312229
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
2021-04-21 15:57:05 +00:00
Russ Cox d4b2638234 all: go fmt std cmd (but revert vendor)
Make all our package sources use Go 1.17 gofmt format
(adding //go:build lines).

Part of //go:build change (#41184).
See https://golang.org/design/draft-gobuild

Change-Id: Ia0534360e4957e58cd9a18429c39d0e32a6addb4
Reviewed-on: https://go-review.googlesource.com/c/go/+/294430
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-02-20 03:54:50 +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
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
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2020-09-23 18:12:59 +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 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
Joshua M. Clulow f686a2890b all: add new GOOS=illumos, split out of GOOS=solaris
Like GOOS=android which implies the "linux" build tag, GOOS=illumos
implies the "solaris" build tag. This lets the existing ecosystem of
packages still work on illumos, but still permits packages to start
differentiating between solaris and illumos.

Fixes #20603

Change-Id: I8f4eabf1a66060538dca15d7658c1fbc6c826622
Reviewed-on: https://go-review.googlesource.com/c/go/+/174457
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-04-30 16:59:13 +00:00
Josh Bleecher Snyder 06c86e0fc3 syscall: optimize SlicePtrFromStrings
Instead of allocating a byte slice for every string,
calculated the required size and create
a single slice big enough to hold all of them.
As an added benefit, any error encountered
will now be returned before allocations occur.

os/exec package benchmarks:

name        old time/op    new time/op    delta
ExecEcho-8    2.14ms ± 1%    2.14ms ± 3%     ~     (p=0.842 n=10+9)

name        old alloc/op   new alloc/op   delta
ExecEcho-8    6.35kB ± 0%    6.18kB ± 0%   -2.65%  (p=0.000 n=10+10)

name        old allocs/op  new allocs/op  delta
ExecEcho-8      69.0 ± 0%      36.0 ± 0%  -47.83%  (p=0.000 n=10+10)

Change-Id: I84118d8473037d873f73903d4e4f6ed14f531ce7
Reviewed-on: https://go-review.googlesource.com/c/164961
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-02 20:13:13 +00:00
Keith Randall c9762b8a7e syscall: move uses of Syscall to libSystem on darwin
Miscellaneous additional conversions from raw syscalls
to using their libc equivalent.

Update #17490

Change-Id: If9ab22cc1d676c1f20fb161ebf02b0c28f71585d
Reviewed-on: https://go-review.googlesource.com/c/148257
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-11-08 03:01:54 +00:00
Clément Chigot 49be65eeba syscall: change solaris files to libc files
AIX and Solaris both requires libc to make any syscalls and their
implementation is really similar.
Therefore, Solaris files reused by AIX have their name changed to *_libc.

exec_libc.go is also adapted to AIX.

Updates: #25893

Change-Id: I50d1d7b964831637013d5e64799187cd9565c42b
Reviewed-on: https://go-review.googlesource.com/c/138719
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-10 00:58:17 +00:00
Shawn Walker-Salas 2d1bd1fe9d syscall: fix Exec on solaris
The test added for issue #18146 exposed a long-existing bug in the
Solaris port; notably, that syscall.Exec uses RawSyscall -- which is not
actually functional for the Solaris port (intentionally) and only exists
as a placebo to satisfy build requirements.

Call syscall.execve instead for Solaris.

Fixes #20832

Change-Id: I327d863f4bbbbbb6e5ecf66b82152c4030825d09
Reviewed-on: https://go-review.googlesource.com/47032
Run-TryBot: Shawn Walker-Salas <shawn.walker@oracle.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-06-28 19:02:05 +00:00
John R. Lenton 91139b87f7 runtime, syscall: workaround for bug in Linux's execve
Linux's execve has (at the time of writing, and since v2.6.30) a bug when it ran
concurrently with clone, in that it would fail to set up some datastructures if
the thread count before and after some steps differed. This is described better
and in more detail by Colin King in Launchpad¹ and kernel² bugs. When a program
written in Go runtime.Exec's a setuid binary, this issue may cause the resulting
process to not have the expected uid. This patch works around the issue by using
a mutex to serialize exec and clone.

1. https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1672819
2. https://bugzilla.kernel.org/show_bug.cgi?id=195453

Fixes #19546

Change-Id: I126e87d1d9ce3be5ea4ec9c7ffe13f92e087903d
Reviewed-on: https://go-review.googlesource.com/43713
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-06-20 23:53:17 +00:00
Wander Lairson Costa 79f6a5c7bd syscall: only call setgroups if we need to
If the caller set ups a Credential in os/exec.Command,
os/exec.Command.Start will end up calling setgroups(2), even if no
supplementary groups were given.

Only root can call setgroups(2) on BSD kernels, which causes Start to
fail for non-root users when they try to set uid and gid for the new
process.

We fix by introducing a new field to syscall.Credential named
NoSetGroups, and setgroups(2) is only called if it is false.
We make this field with inverted logic to preserve backward
compatibility.

RELNOTES=yes

Change-Id: I3cff1f21c117a1430834f640ef21fd4e87e06804
Reviewed-on: https://go-review.googlesource.com/36697
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-02-17 14:36:27 +00:00
Kevin Burke 8d1d9292ff syscall: document that Exec wraps execve(2)
Change-Id: I611511434f37c75f77c22f61f469108243bc0101
Reviewed-on: https://go-review.googlesource.com/29121
Reviewed-by: Russ Cox <rsc@golang.org>
2016-10-12 15:02:57 +00:00
Marvin Stenger d0fb649713 all: use &^ operator if possible
This is a change improving consistency in the source tree.
The pattern foo &= ^bar, was only used six times in src/ directory.
The usage of the supported &^ (bit clear / AND NOT) operator is way more
common, about factor 10x.

Change-Id: If26a2994fd81d23d42189bee00245eb84e672cf3
Reviewed-on: https://go-review.googlesource.com/21224
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-29 14:28:41 +00:00
Brad Fitzpatrick 5fea2ccc77 all: single space after period.
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.

This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:

$ perl -i -npe 's,^(\s*// .+[a-z]\.)  +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.)  +([A-Z])')
$ go test go/doc -update

Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-02 00:13:47 +00:00
Shenghou Ma 3925a7c5db all: switch to the new deprecation convention
While we're at it, move some misplaced comment blocks around.

Change-Id: I1847d7f1ca1dbb8e5de737203c4ed6c66e112508
Reviewed-on: https://go-review.googlesource.com/10188
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-06-18 19:16:23 +00:00
Russ Cox c007ce824d build: move package sources from src/pkg to src
Preparation was in CL 134570043.
This CL contains only the effect of 'hg mv src/pkg/* src'.
For more about the move, see golang.org/s/go14nopkg.
2014-09-08 00:08:51 -04:00