Activity log for bug #1643167

Date Who What changed Old value New value Message
2016-11-19 11:29:52 thiner bug added bug
2016-11-19 11:30:52 thiner description Bash itself won't crash on extraordinarily input, but the little utilitarian tool crashes. With the ulimit set in /etc/bash.bashrc, the crash info is graceful as seen below. However, it ended up crashing my computer out. (Actually it took my computer into the pitfall of swap, as I found out later. That means, it consumes too much MEMORY, not cpu time.) The source code seems as if the spelling error candidates are O(n^2). (Although actually it is, at least.) Possibly a denial of service attack on computer without good config on ulimit :) ~# `printf '=%.0s' {1..10000}` Sorry, command-not-found has crashed! Please file a bug report at: https://bugs.launchpad.net/command-not-found/+filebug Please include the following information with the report: command-not-found version: 0.3 Python version: 3.5.2 final 0 Distributor ID: Ubuntu Description: Ubuntu 16.04.1 LTS Release: 16.04 Codename: xenial Exception information: Traceback (most recent call last): File "/usr/lib/python3/dist-packages/CommandNotFound/util.py", line 24, in crash_guard callback() File "/usr/lib/command-not-found", line 90, in main if not cnf.advise(args[0], options.ignore_installed) and not options.no_failure_msg: File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 267, in advise self.print_spelling_suggestion(command) File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 143, in print_spelling_suggestion for w in similar_words(word): File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 102, in similar_words replaces = [a + c + b[1:] for a, b in s for c in alphabet if b] File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 102, in <listcomp> replaces = [a + c + b[1:] for a, b in s for c in alphabet if b] MemoryError Bash itself won't crash on extraordinarily long input, but the little utilitarian tool will. With the ulimit set in /etc/bash.bashrc, the crash info is graceful as seen below. However, it ended up crashing my computer out. (Actually it took my computer into the pitfall of swap, as I found out later. That means, it consumes too much MEMORY, not cpu time.) The source code seems as if the spelling error candidates are O(n^2). (Although actually it is, at least.) Possibly a denial of service attack on computer without good config on ulimit :) ~# `printf '=%.0s' {1..10000}` Sorry, command-not-found has crashed! Please file a bug report at: https://bugs.launchpad.net/command-not-found/+filebug Please include the following information with the report: command-not-found version: 0.3 Python version: 3.5.2 final 0 Distributor ID: Ubuntu Description: Ubuntu 16.04.1 LTS Release: 16.04 Codename: xenial Exception information: Traceback (most recent call last):   File "/usr/lib/python3/dist-packages/CommandNotFound/util.py", line 24, in crash_guard     callback()   File "/usr/lib/command-not-found", line 90, in main     if not cnf.advise(args[0], options.ignore_installed) and not options.no_failure_msg:   File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 267, in advise     self.print_spelling_suggestion(command)   File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 143, in print_spelling_suggestion     for w in similar_words(word):   File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 102, in similar_words     replaces = [a + c + b[1:] for a, b in s for c in alphabet if b]   File "/usr/lib/python3/dist-packages/CommandNotFound/CommandNotFound.py", line 102, in <listcomp>     replaces = [a + c + b[1:] for a, b in s for c in alphabet if b] MemoryError
2016-11-27 16:14:11 Dominique Ramaekers command-not-found: status New Confirmed
2016-11-27 16:14:23 Dominique Ramaekers command-not-found: assignee Dadio (dominique-ramaekers)
2016-11-29 18:33:10 Dominique Ramaekers command-not-found: status Confirmed In Progress
2016-11-29 18:45:01 Launchpad Janitor branch linked lp:~dominique-ramaekers/command-not-found/thinerBug
2016-11-29 18:57:21 Dominique Ramaekers command-not-found: importance Undecided High
2016-11-29 18:57:31 Dominique Ramaekers command-not-found: status In Progress Fix Committed
2016-12-13 06:57:35 Launchpad Janitor branch linked lp:~ubuntu-core-dev/command-not-found/ubuntu
2017-07-30 15:46:47 Dominique Ramaekers command-not-found: status Fix Committed Fix Released
2017-09-02 05:20:38 Dominique Ramaekers information type Private Security Public Security
2020-10-14 16:37:45 Noah Gorny branch unlinked lp:command-not-found