Bug#934301: ack searches the output file creating a loop

[ali]

Package: ack
Version: 2.24-1
Severity: critical
Justification: causes serious data loss

Dear Maintainer,

   * What led up to the situation?
     Searching a string in a folder with only a single file in it.

   * What exactly did you do (or not do) that was effective (or
     ineffective)?
     I've run "ack Time > time.txt" in a folder that had only one file
     in it (8MB mysql-slow.log.1 to be exact).

   * What was the outcome of this action?
     time.txt file ended up being 14GB in size, filling the disk to 100%
     and crashing the database.

   * What outcome did you expect instead?
     A similar outcome with "ack Time mysql-slow.log.1 > time.txt" which
     results in an output 135KB file.

   * To recreate the problem the file that is being searched needs to be
     big enough, the string that is being searched needs to be scarce
     enough and the output filename should not contain the searched
     string. I can provide the file if needed.

-- System Information:
Debian Release: 10.0
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.19.0-5-amd64 (SMP w/4 CPU cores)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US:en (charmap=UTF-8)
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages ack depends on:
ii  libfile-next-perl  1.16-2
ii  perl               5.28.1-6

ack recommends no packages.

ack suggests no packages.

-- no debconf information