Package: bash
Version: 5.1-2+b3
Severity: important

Dear Maintainer,

The error was detected by the script that generates Kubernetes Secret
objects. For safety, the script checked the text saved to the file with the
original content of the bash variable. For such a check the script read the
contents of the file into another variable and compared its value with the
original value.

The error appears consistently with LANG="en_US.UTF-8" in the Google Cloud
Shell container and in an AWS EC2 virtual machine created from an AMI
Debian 11 image
(AMI ID: ami-0fc5afe6a259e0ed4).
If LANG=C, then the error disappears.

The frequency of the error depends on the specific content of the bash
script (or its size) and some indirect circumstances of the script being
run.

It should be noted that the cause of the error is very difficult to
diagnose, so the number of users actually affected by it is unknown.

Attached to the letter is the script example with specific data, which
periodically generates the specified error. Run the script several times to
observe the error (~10):

   rm -f output1.txt output2.txt output3.txt
   MYUTF8=' ... ';
   echo -n "$MYUTF8" > "output1.txt"
   echo    "$( < output1.txt )" > output2.txt
   MYINPUT="$( < output1.txt )"
   echo    "$MYINPUT"           > output3.txt
   if ! diff output2.txt output3.txt ; then
      echo -e "\noutput2.txt and output3.txt files should be the same, but
they are different!\n"
   fi

Example of data corruption:

$ diff output2.txt output3.txt
11c11
<
 
ввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввввв
---
>
 
ввввввввввввввввввввввввввввввввввввввввввввввввввР�вввввввввввввввввввввввввввввввввввввв

Regards,
Vladimir Vinogradov

-- System Information:

$ cat /etc/os-release
  PRETTY_NAME="Debian GNU/Linux 11 (bullseye)"
  NAME="Debian GNU/Linux"
  VERSION_ID="11"
  VERSION="11 (bullseye)"
  VERSION_CODENAME=bullseye
  ID=debian

Debian Release: 11.3
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500,
'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 5.10.0-14-cloud-amd64 (SMP w/2 CPU threads)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE
not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages bash depends on:
ii  base-files   11.1+deb11u3
ii  debianutils  4.11.2
ii  libc6        2.31-13+deb11u3
ii  libtinfo6    6.2+20201114-2

Versions of packages bash recommends:
ii  bash-completion  1:2.11-2

Versions of packages bash suggests:
pn  bash-doc  <none>

-- no debconf information

Attachment: bash_5.1-2_debian-11_bug
Description: Binary data

Reply via email to