[ANNOUNCEMENT] Updated: bash-4.3.39-2

[ANNOUNCEMENT] Updated: bash-4.3.39-2

[Eric Blake (cygwin)]

[-- Attachment #1: Type: text/plain, Size: 6616 bytes --]

A new release of bash, 4.3.39-2, has been uploaded and will soon reach a
mirror near you; leaving 4.3.33-1 as the previous version.

NEWS:
=====
This is my second build of bash 4.3 for cygwin, incorporating several
new upstream official patches and working around a change in make 4.1
VPATH behavior.

I am aware of an issue reported with using bash on text mode mounts, but
have not yet had time to investigate if the fault lies in bash or in
cygwin1.dll; this build was done solely as a refresh to a newer
patchlevel while I still investigate.

This build of bash is immune to the ShellShock vulnerabilities (although
unpatched bash 4.3 is vulnerable, the official upstream patches solve
the issue).  By now, you should no longer be running a vulnerable bash,
but to double check you can run the following test to make sure you are
not subject to arbitrary remote code execution due to ShellShock:
$ env 'bad=() { echo vulnerable; }' bash -c bad

If it prints "bash: bad: command not found", your version of bash is
safe and not subject to remote exploits.  If it prints "vulnerable", you
need to upgrade now.

There are a few things you should be aware of before using this version:
1. When using binary mounts, cygwin programs try to emulate Linux.  Bash
on Linux does not understand \r\n line endings, but interprets the \r
literally, which leads to syntax errors or odd variable assignments.
Therefore, you will get the same behavior on Cygwin binary mounts by
default.
2. d2u is your friend.  You can use it to convert any problematic script
into binary line endings.
3. Cygwin text mounts automatically work with either line ending style,
because the \r is stripped before bash reads the file.  If you
absolutely must use files with \r\n line endings, consider mounting the
directory where those files live as a text mount.  However, text mounts
are not as well tested or supported on the cygwin mailing list, so you
may encounter other problems with other cygwin tools in those directories.
4. This version of bash has a cygwin-specific set option, named "igncr",
to force bash to ignore \r, independently of cygwin's mount style.  As
of bash-3.2.3-5, it controls regular scripts, command substitution, and
sourced files.  I hope to convince the upstream bash maintainer to
accept this patch into a future bash release even on Linux, rather than
keeping it a cygwin-specific patch, but only time will tell.  There are
several ways to activate this option:
4a. For a single affected script, add this line just after the she-bang:
 (set -o igncr) 2>/dev/null && set -o igncr; # comment is needed
4b. For a single script, invoke bash explicitly with the option, as in
'bash -o igncr ./myscript' rather than the simpler './myscript'.
4c. To affect all scripts, export the environment variable BASH_ENV,
pointing to a file that sets the shell option as desired.  Bash will
source this file on startup for every script.
4d. Added in the bash-3.2-2 release: export the environment variable
SHELLOPTS with igncr included in it.  It is read-only from within bash,
but you can set it before invoking bash; once in bash, it auto-tracks
the current state of 'set -o igncr'.  If exported, then all bash child
processes inherit the same option settings; with the exception added in
3.2.9-11 that certain interactive options are not inherited in
non-interactive use.
4e. bash-4.1.9-1 dropped support for 'shopt -s igncr'; it did not make
sense to support the option through both set and shopt, and SHELLOPTS
proved to be more powerful.
5. You can also experiment with the IFS variable for controlling how
bash will treat \r during variable expansion.
6. There are varying levels of speed at which bash operates.  The
fastest is on a binary mount with igncr disabled (the default behavior).
 Next would be text mounts with igncr disabled and no \r in the
underlying file. Next would be binary mounts with igncr enabled.  And
the slowest that bash will operate is on text mounts with igncr enabled.
7. As additional cygwin extensions, this version of bash includes:
7a. EXECIGNORE - a colon-separated list of glob patterns to ignore
when completing on executables.  EXECIGNORE=*.dll is common.
7b. completion_strip_exe - using 'shopt -s completion_strip_exe'
makes completion strip .exe suffixes
8. This version of bash is immune to ShellShock (CVE-2014-6271 and
friends) because it exports functions via 'BASH_FUNC_foo%%=' rather than
'foo=' environment variables.  However, doing this has exposed
weaknesses in some other utilities like 'ksh' or 'at' that fail to scrub
their environment to exclude what is not a valid name for them.
9. If you don't like how bash behaves, then propose a patch, rather than
proposing idle ideas.  This turn of events has already been talked to
death on the mailing lists by people with many ideas, but few patches.
Thanks to Dan Colascione for providing the EXECIGNORE and
completion_strip_exe patches.

Remember, you must not have any bash or /bin/sh instances running when
you upgrade the bash package.  This release requires cygwin-2.0.2-1 or
later.  See also the upstream documentation in
/usr/share/doc/bash/.

DESCRIPTION:
============
Bash is an sh-compatible shell that incorporates useful features from
the Korn shell (ksh) and C shell (csh).  It is intended to conform to
the IEEE POSIX P1003.2/ISO 9945.2 Shell and Tools standard.  It offers
functional improvements over sh for both programming and interactive
use. In addition, most sh scripts can be run by Bash without modification.

As of the bash 3.0 series, cygwin /bin/sh defaults to bash, not ash,
similar to some Linux distributions (although /bin/sh may swap to dash
at some future time).

UPDATE:
=======
To update your installation, click on the "Install Cygwin now" link on
the http://cygwin.com/ web page.  This downloads setup.exe to your
system. Save it and run setup, answer the questions and pick up 'bash'
in the 'Base' category (it should already be selected).

DOWNLOAD:
=========
Note that downloads from cygwin.com aren't allowed due to bandwidth
limitations.  This means that you will need to find a mirror which has
this update, please choose the one nearest to you:
http://cygwin.com/mirrors.html

QUESTIONS:
==========
If you want to make a point or ask a question the Cygwin mailing list is
the appropriate place.

-- 
Eric Blake
volunteer cygwin bash package maintainer

For more details on this list (including unsubscription), see:
http://sourceware.org/lists.html



[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Mikhail Usenko]

Eric Blake (cygwin) <...> wrote:
> 4.3.39-2

Hello, Eric.
It has the same issue as in the previous version:
eating one \r from the odd numbered chains of the \r.

bash-4.3.39-2
-------------
$ echo -ne "\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0a
0000001
$ echo -ne "\r\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0a
0000003
$ echo -ne "\r\r\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0a
0000003
$ echo -ne "\r\r\r\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0d 0d 0a
0000005
$ echo -ne "\r\r\r\r\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0d 0d 0a
0000005

$ echo -ne "\r\r\r\r" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0d 0d 0a
0000005
$ echo -ne "\r\r\r\r\r" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0d 0d 0a
0000005


bash-4.3.33-1
-------------
$ echo -ne "\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0a
0000001
$ echo -ne "\r\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0a
0000003
$ echo -ne "\r\r\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0a
0000003
$ echo -ne "\r\r\r\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0d 0d 0a
0000005
$ echo -ne "\r\r\r\r\r\n" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0d 0d 0a
0000005

$ echo -ne "\r\r\r\r" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0d 0d 0a
0000005
$ echo -ne "\r\r\r\r\r" | { read t; echo "$t"; } | od -tx1
0000000 0d 0d 0d 0d 0a
0000005


-- 


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 639 bytes --]

On 06/04/2015 03:51 AM, Mikhail Usenko wrote:
> Eric Blake (cygwin) <...> wrote:
>> 4.3.39-2
> 
> Hello, Eric.
> It has the same issue as in the previous version:
> eating one \r from the odd numbered chains of the \r.

Yes, I know there are still \r issues, although I appreciate the test
case as I'm not sure I have seen this particular complaint.

> $ echo -ne "\r\n" | { read t; echo "$t"; } | od -tx1

'echo -ne' is non-portable (I can break it with 'shopt -s xpg_echo');
get used to using 'printf' instead.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 433 bytes --]

On 06/04/2015 03:51 AM, Mikhail Usenko wrote:
> Eric Blake (cygwin) <...> wrote:
>> 4.3.39-2
> 
> Hello, Eric.
> It has the same issue as in the previous version:
> eating one \r from the odd numbered chains of the \r.
> 

Please try the (currently-experimental) 4.3.42-4, which should fix the
issues observed.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Mikhail Usenko]

On Thu, 24 Sep 2015 15:10:25 -0600
Eric Blake <...> wrote:
> On 06/04/2015 03:51 AM, Mikhail Usenko wrote:
> > Eric Blake (cygwin) <...> wrote:
> >> 4.3.39-2
> > 
> > Hello, Eric.
> > It has the same issue as in the previous version:
> > eating one \r from the odd numbered chains of the \r.
> > 
> 
> Please try the (currently-experimental) 4.3.42-4, which should fix the
> issues observed.
> 

On Thu, 24 Sep 2015 10:55:45 -0600
Eric Blake <...> wrote:
> 
> Jeff Downs helped me investigate off-list, and I think he found the
> culprit (a typo in input.c that requested O_TEXT when it meant B_TEXT,
> when mapping from open() flags to bash's internal B_* flags). I'm
> building a new bash build right now, and will shortly be posting it for
> testing.
> 


Hello, Eric.
Thank you for working on this annoying problem that stops
some parsing scripts (that worked in cygwin in 3-4 bash versions ago)
to work correctly and thereby so the cygwin/bash overall employing.
But catching that bug (in upstream?) hasn't changed anything
at least on my installation:

---%<---<cygwin-test.sh>---%<---
#! /bin/bash
bash -version | head -n1
echo

sender()
{
  echo -n  '\r\n' >&2
  echo -ne '\r\n'
  sleep 1
  echo -n  '\r\r\n' >&2
  echo -ne '\r\r\n'
  sleep 1
  echo -n  '\r\r\r\n' >&2
  echo -ne '\r\r\r\n'
  sleep 1
  echo -n  '\r\r\r\r\n' >&2
  echo -ne '\r\r\r\r\n'
  sleep 1
  echo -n  '\r\r\r\r\r\n' >&2
  echo -ne '\r\r\r\r\r\n'
  sleep 1
}

receiver()
{
  t=""
  while read t || [ "$t" ]; do
    echo -ne ": \t"
    od -A n -t x1  <<<"$t"
  done  >&2
}


# implicit pipe
receiver < <(sender)

# explicit pipeline
sender | receiver
--->%---<cygwin-test.sh>--->%---


$ ./cygwin-test.sh
GNU bash, version 4.3.42(4)-release (x86_64-unknown-cygwin)

\r\n:    0a
\r\r\n:          0d 0d 0a
\r\r\r\n:        0d 0d 0a
\r\r\r\r\n:      0d 0d 0d 0d 0a
\r\r\r\r\r\n:    0d 0d 0d 0d 0a
\r\n:    0a
\r\r\n:          0d 0d 0a
\r\r\r\n:        0d 0d 0a
\r\r\r\r\n:      0d 0d 0d 0d 0a
\r\r\r\r\r\n:    0d 0d 0d 0d 0a


-- 
Mike


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 1311 bytes --]

On 09/28/2015 08:30 AM, Mikhail Usenko wrote:

> But catching that bug (in upstream?) hasn't changed anything
> at least on my installation:

Okay, so it sounds like your issue is separate.

> 
> ---%<---<cygwin-test.sh>---%<---
> #! /bin/bash
> bash -version | head -n1
> echo
> 
> sender()
> {
>   echo -n  '\r\n' >&2
>   echo -ne '\r\n'

'echo -n' and 'echo -e' are non-portable (even in bash; because I can
use 'shopt -s xpgecho' to get POSIX-mandated behavior).  Use 'printf'
instead.


> receiver()
> {
>   t=""
>   while read t || [ "$t" ]; do
>     echo -ne ": \t"
>     od -A n -t x1  <<<"$t"
>   done  >&2
> }
> 
> 
> # implicit pipe
> receiver < <(sender)
> 
> # explicit pipeline
> sender | receiver

Okay, I can see the disappearing \r even on a binary mount, so it
appears to be unrelated to the fix for text mounts.

Meanwhile, doing something like this (with a shorter sender):

# sender | od -An -tx1
\r\n\r\r\n\r\r\r\n 0d 0a 0d 0d 0a 0d 0d 0d 0a

shows that the pipeline is not eating the \r, but rather it appears to
be an issue in 'read'.  I'm still investigating, but thanks for the
recipe, as it gives me something to focus on.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 758 bytes --]

On 09/28/2015 09:04 AM, Tim Higgins wrote:
> Team 
> When I run startx I get the following error.
> higginst@HigginsT-LT-W7 ~
> $ startx
> 

And this is related to bash, how?

Please don't top-post or commandeer unrelated threads. If you have an
unrelated question, start a new thread.


> 
> 
> CONFIDENTIALITY:  This e-mail (including any attachments) may contain confidential,

And also please don't send unenforceable legalese to this
publicly-archived list. If your employer mandates this junk, then send
from a different account (gmane is one way to post to this list via the
web rather than an employer-botched email).

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Mikhail Usenko]

On Mon, 28 Sep 2015 08:56:14 -0600
Eric Blake <...> wrote:
> 
> 'echo -n' and 'echo -e' are non-portable (even in bash; because I can
> use 'shopt -s xpgecho' to get POSIX-mandated behavior).  Use 'printf'
> instead.
> 

xpg_echo doesn't change 'echo -ne' behavior
('echo -e' force backslash-escape sequences expansion independently)

$ shopt xpg_echo
xpg_echo        off
$ echo -e '\r\n' | od -tx1
0000000 0d 0a 0a
0000003
$ shopt -s xpg_echo
$ shopt xpg_echo
xpg_echo        on
$ echo -e '\r\n' | od -tx1
0000000 0d 0a 0a
0000003
$ echo '\r\n' | od -tx1
0000000 0d 0a 0a
0000003



-- 
Mike


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 749 bytes --]

On 09/28/2015 10:48 AM, Mikhail Usenko wrote:
> On Mon, 28 Sep 2015 08:56:14 -0600
> Eric Blake <...> wrote:
>>
>> 'echo -n' and 'echo -e' are non-portable (even in bash; because I can
>> use 'shopt -s xpgecho' to get POSIX-mandated behavior).  Use 'printf'
>> instead.
>>
> 
> xpg_echo doesn't change 'echo -ne' behavior

xpg_echo in isolation does not, and POSIXLY_CORRECT in isolation does
not, but together they DO affect echo:

$ bash -c 'echo -n hi'
hi
$ bash -c 'shopt -s xpg_echo; echo -n hi'
hi
$ bash -c 'POSIXLY_CORRECT=1; echo -n hi'
hi
$ bash -c 'POSIXLY_CORRECT=1; shopt -s xpg_echo; echo -n hi'
-n hi

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]

Re: [ANNOUNCEMENT] Updated: bash-4.3.39-2

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 981 bytes --]

On 09/28/2015 08:56 AM, Eric Blake wrote:
> On 09/28/2015 08:30 AM, Mikhail Usenko wrote:
> 
>> But catching that bug (in upstream?) hasn't changed anything
>> at least on my installation:
> 

> Okay, I can see the disappearing \r even on a binary mount, so it
> appears to be unrelated to the fix for text mounts.
> 
> Meanwhile, doing something like this (with a shorter sender):
> 
> # sender | od -An -tx1
> \r\n\r\r\n\r\r\r\n 0d 0a 0d 0d 0a 0d 0d 0d 0a
> 
> shows that the pipeline is not eating the \r, but rather it appears to
> be an issue in 'read'.  I'm still investigating, but thanks for the
> recipe, as it gives me something to focus on.

I think I've figured out the problem in the 'read' builtin, and the new
bash-4.3.43-5 should fix it. Please test to make sure.

https://lists.gnu.org/archive/html/bug-bash/2016-08/msg00010.html

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]