[Bug 1878517] [NEW] please apply bash 5.0 patch 17

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You have been subscribed to a public bug by Matthieu Clemenceau (mclemenceau):

This section is for Focal SRU purpose

[Impact]
>From https://ftp.gnu.org/gnu/bash
There were cases where bash 5.0 patch 16 reaped process substitution file descriptors (or FIFOs) and processes to early. This is a better fix for the problem that bash50-016 attempted to solve.

[Test Case]
This simple bash script pass when bash with patch 017 is installed
Recommend to run it before and after installing the update to notice the difference

```
#!/usr/bin/bash

ouch() {
    cat < <(echo bar)
    cat "$1"
}

ouch2() {
    { cat; } < <(echo bar)
    cat "$1"
}

ouch <(echo "foo")
ouch2 <(echo "foo")
```
Expected output with the patch installed:

foo
bar
foo
bar

[Regression Potential]
This is an upstream patch level update with no additional modification. The regression potential should be fairly low. Also the patch is intended to only fix this problem.
Possible regression would be unforeseen additional process substitutions that upstream bash would share.
  
End SRU
------
Original Bug Description:

I am using Ubuntu 20.04 for development and has hit a bug in bash 5.0
patch 16.

I can't reproduce it in pure bash, but with bats from https://github.com
/bats-core/bats-core/ it is very easy to repro:

```
# cat << EOF > ya.bats
check() {
 echo "check $@"
 ls -l /proc/self/fd
}

@test "here file" {
 check -p <(echo "hey")
 false
}
EOF

$ bats ya.bats
```

Normally the output should contain the line

   lr-x------ 1 kir kir 64 May 14 02:01 63 -> pipe:[4616918]

which is a result of a "here file" created by bash via <(echo "hey").

In my testing, about 50% of runs don't have /dev/fd/63 listed.

I found out this is a manifest of a bug introduced in bash 5.0 patch 16
(see http://ftp.gnu.org/gnu/bash/bash-5.0-patches/bash50-016)

The bug is fixed in 5.0 patch 17 (see
http://ftp.gnu.org/gnu/bash/bash-5.0-patches/bash50-017).

Please update bash to patchlevel 17.

** Affects: bash (Ubuntu)
     Importance: Medium
     Assignee: Matthieu Clemenceau (mclemenceau)
         Status: Fix Released

** Affects: bash (Ubuntu Focal)
     Importance: Medium
     Assignee: Matthieu Clemenceau (mclemenceau)
         Status: In Progress


** Tags: id-5ec6a2b21639eb7938a123eb
-- 
please apply bash 5.0 patch 17
https://bugs.launchpad.net/bugs/1878517
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