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=195453Fixes#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>
This certainly won't get inlined right now, but in the spirit of
making this more robust, we have to disable inlining because inlining
would defeat the purpose of separating forkAndExecInChild1 into a
separate function.
Updates #20732.
Change-Id: I736c3f909cc42c5f5783740c2e19ba4827c7c2ec
Reviewed-on: https://go-review.googlesource.com/46174
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Currently, CLONE_VFORK is used without much regard to the stack. This
is dangerous, because anything the child does to the stack is visible
to the parent. For example, if the compiler were to reuse named stack
slots (which it currently doesn't do), it would be easy for the child
running in the same stack frame as the parent to corrupt local
variables that the parent then depended on. We're not sure of anything
specific going wrong in this code right now, but it is at best a
ticking time bomb.
CLONE_VFORK can only safely be used if we ensure the child does not
execute in any of the active stack frames of the parent. This commit
implements this by arranging for the parent to return immediately from
the frame the child will operate in, and for the child to never return
to the frame the parent will operate in.
Fixes#20732.
Change-Id: Iad5b4ddc2b994c082bd278bfd52ef53bd38c037f
Reviewed-on: https://go-review.googlesource.com/46173
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This reverts commit 3d13b5e00c.
Reason for revert: the new TestHttpsInsecure test breaks two darwin builders, the android builders, and one plan9 builder.
Change-Id: I09158e7d1bd2b3ffda57e7f2350f34eb9b62e784
Reviewed-on: https://go-review.googlesource.com/46158
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This adds a qualified mention of golang/dep to the FAQ.
Fixes#19049
Change-Id: I42a114a008a6ca1250d849872dd98fd6523fa659
Reviewed-on: https://go-review.googlesource.com/46005
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
If you have BenchmarkX1 with sub-benchmark Y
and you have BenchmarkX2 with no sub-benchmarks,
then
go test -bench=X/Y
runs BenchmarkX1 once with b.N=1 (to find out about Y)
and then not again, because it has sub-benchmarks,
but arguably also because we're interested in Y.
In contrast, it runs BenchmarkX2 in full, even though clearly
that is not relevant to the match X/Y. We do have to run X2
once with b.N=1 to probe for having X2/Y, but we should not
run it with larger b.N.
Fixes#20589.
Change-Id: Ib86907e844f34dcaac6cd05757f57db1019201d0
Reviewed-on: https://go-review.googlesource.com/46031
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
This is a runtime version of sync.RWMutex that can be used by code in
the runtime package. The type is not quite the same, in that the zero
value is not valid.
For future use by CL 43713.
Updates #19546
Change-Id: I431eb3688add16ce1274dab97285f555b72735bf
Reviewed-on: https://go-review.googlesource.com/45991
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This doesn't change the existing restriction with disallows
spaces in import paths (as found in an import declaration).
It simply permits packages to be under a directory name that
may contain spaces.
Verified manually that it works. This could use a test, but the
change is trivial. We also can't use the existing test framework
(under test/) because the way those tests are run with test/run.go,
the mechanims for compiling a directory, even if it contains blanks
it its name, does't produce compiler paths with blanks
(the compilation is local).
Fixes#20306.
Change-Id: I6cbffb86c3394347897c3c94b110da0aadc5bfdf
Reviewed-on: https://go-review.googlesource.com/46001
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Changed link for cover from x-tools to correct
Fix#20662
Change-Id: I9b839ed952e9abb12b3d1655ac4cf5976f374a4b
Reviewed-on: https://go-review.googlesource.com/46012
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
OpenBSD no longer has procfs.
Based on a patch by Matthieu Sarter.
Fixes#19453.
Change-Id: Ia09d16f8a1cbef2f8cc1c5f49e9c61ec7d026a40
Reviewed-on: https://go-review.googlesource.com/46004
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Updates http2 to x/net/http2 git rev 973f3f3 for:
http2: make Transport treat http.NoBody like it were nil
https://golang.org/cl/45993
Updates #18891
Change-Id: I846ccf286992ed2c6249014e51fdeb40b35e50ed
Reviewed-on: https://go-review.googlesource.com/46000
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Only forget about it if the context timed out, as the comment says.
Fixes#20703.
Change-Id: Ie6234f1a32f85e6bfd052dc24a33aa63b8883c37
Reviewed-on: https://go-review.googlesource.com/45999
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Per email from acoshift.
Change-Id: Ieb79244d17623e112a385e6b43843d3ffb185cf6
Reviewed-on: https://go-review.googlesource.com/45995
Reviewed-by: Matt Layher <mdlayher@gmail.com>
Make it clearer that -test=X/Y runs all the tests matching X,
even if they don't have sub-tests matching Y.
Fixes#20589.
Change-Id: Ic27e89e748d60f67b50c68445ec0480066bdf207
Reviewed-on: https://go-review.googlesource.com/46030
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The ascii85, base32 and base64 packages all contain a test called
TestDecoderBuffering. Each of these tests contain a loop that ignores
the error returned from the Read method of their decoders. The result
being that the tests loop for ever if the decoders actually return an
error. This commit fixes the issue by terminating the loops if an error
occurs and failing the tests with a suitable error message.
Change-Id: Idb385673cf9f3f6f8befe4288b4be366ab0985fd
Reviewed-on: https://go-review.googlesource.com/46010
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
If an image has been cropped horizontally, writeImageBlock detects that
its width and Stride differ and acts accordingly.
However, if an image has been cropped vertically, trimming from the
bottom, the whole original image will be written in place. This results
in more data in the LZW stream than necessary, and many decoders
including image/gif's itself will fail to load.
Fixes#20692
Change-Id: Id332877e31bcf3729c89d8a50c1be0464028d82e
Reviewed-on: https://go-review.googlesource.com/45972
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Run-TryBot: Nigel Tao <nigeltao@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Nigel Tao <nigeltao@golang.org>
In some cases the netpoll code can cause a spurious wakeup. This is
normally harmless, as the woken up code simply retries the operation.
However, for connect, the test we were using to see whether the
connect had succeeded (setsockopt(SO_ERROR)) was not reliable in the
case of a spurious wakeup. Change to using a reliable test (getpeername).
On Darwin we used a different technique: a second call to connect;
change Darwin to use getpeername as well.
Return the result of getpeername to avoid having to call it twice.
Fixes#19289.
Change-Id: I119ec8e7a41f482f1e590d4c65a37f6103fa22d9
Reviewed-on: https://go-review.googlesource.com/45815
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Minimal reconstruction of reported failure case.
Manually verified that test fails with CL 45911 reverted.
Change-Id: Ia5d11500d91b46ba1eb5d841db3987edb9136c39
Reviewed-on: https://go-review.googlesource.com/45970
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
The existing docs states that, get looks for a branch or tag
that matches the locally installed version of Go.
First, this is only working for "go1", so it could be confusing.
Second, "If no such version exists it retrieves the most recent
version of the package". It's more the default branch, by git defaults,
rather than most recent version.
This should address the potential unclear parts.
Fixes#20320
Change-Id: Id7d727d88dc350c9902974b64fa28c3766f7e245
Reviewed-on: https://go-review.googlesource.com/45890
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Some of the _test.go files in the encoding packages contain a private
function called testEqual that calls testing.Errorf if the arguments
passed to it are unequal. The line numbers output by such calls to
Errorf identify the failure as being in testEqual itself which is not
very useful. This commit fixes the problem by adding a call to the
new t.Helper method in each of the testEqual functions. The line
numbers output when errors do occur now identify the real source of
the error.
Change-Id: I582d1934f40ef2b788116c3811074c67ea882021
Reviewed-on: https://go-review.googlesource.com/45871
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
They were failing when run on 32bit RFS, with 32bit gdb.
(mips64 builder now has 64bit RFS, with gdb 7.9.)
Leaving TestGdbPythonCgo disabled, it behaves as described in #18784.
Fixes#18173
Change-Id: I3c438cd5850b7bfd118ac6396f40c1208bac8c2d
Reviewed-on: https://go-review.googlesource.com/45874
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Before CL 36170, we identified all function bodies that needed to be
exported before writing any export data.
With CL 36170, we started identifying additional functions while
exporting function bodies. As a consequence, we cannot use a
range-based for loop for iterating over function bodies anymore.
Fixes#18895.
Change-Id: I9cbefa8d311ca8c9898c8272b2ac365976b02396
Reviewed-on: https://go-review.googlesource.com/45817
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
These are used by DIV[U] and MOD[U] assembly instructions.
Add a test in the stdlib so we actually exercise linking
to these routines.
Update #19507
Change-Id: I0d8e19a53e3744abc0c661ea95486f94ec67585e
Reviewed-on: https://go-review.googlesource.com/45703
Reviewed-by: Cherry Zhang <cherryyz@google.com>
I thought I was almost done, but had forgot the tools section, hidden
in comments.
Move the comments to a <pre> block, so it's visible in the HTML.
Updates #20587
Change-Id: I1dc22c63d9ee297e44bbb742f03b4a722247dbe8
Reviewed-on: https://go-review.googlesource.com/45811
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Only one TODO remains, for pprof changes.
Updates #20587
Change-Id: Ib67b23adc7851cc96455b0c20649c8e565a4f92a
Reviewed-on: https://go-review.googlesource.com/45810
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The existing code used Type.String() to obtain the name of a type;
specifically type reflect.Method in this case. However, Type.String()
formatting is intended for error messages and uses the format
pkgpath.name instead of pkgname.name if a package (in this case
package reflect) is imported multiple times. As a result, the
reflect.Method type detection failed under peculiar circumstances
(see the included test case).
Thanks to https://github.com/ericlagergren for tracking down
an easy way to make the bug disappear (which in turn directly
led to the underlying cause).
Fixes#19028.
Change-Id: I1b9c5dfd183260a9be74969fe916a94146fc36da
Reviewed-on: https://go-review.googlesource.com/45777
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
