brlin-tw

hi, i'm daniel. i'm a 15-year-old with some programming experience and i do a little bug hunting in my free time. here's the insane story of how I found a single bug that affected over half of all Fortune 500 companies:

say hello to zendesk

If you've spent some time online, you’ve probably come across Zendesk.

Zendesk is a customer service tool used by some of the world’s top companies. It’s easy to set up: you link it to your company’s support email (like [email protected]), and Zendesk starts managing incoming emails and creating tickets. You can handle these tickets yourself or have a support team do it for you. Zendesk is a billion-dollar company, trusted by big names like Cloudflare.

Personally, I’ve always found it surprising that these massive companies, worth billions, rely on third-party tools like Zendesk instead of building their own in-house ticketing systems.

your weakest link

brlin-tw

$ TEST_FILE=/media/brlin/1TB/fio-test.bin TEST_SIZE=10G fio flash-storage-generic.fio
seq-read: (g=0): rw=read, bs=(R) 4096KiB-4096KiB, (W) 4096KiB-4096KiB, (T) 4096KiB-4096KiB, ioengine=libaio, iodepth=8
seq-write: (g=1): rw=write, bs=(R) 4096KiB-4096KiB, (W) 4096KiB-4096KiB, (T) 4096KiB-4096KiB, ioengine=libaio, iodepth=8
rand-read: (g=2): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=32
rand-write: (g=3): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=32
fio-3.36
Starting 4 processes
seq-read: Laying out IO file (1 file / 10256MiB)
Jobs: 1 (f=1): [_(2),r(1),P(1)][34.3%][r=48.0MiB/s,w=392MiB/s][r=12.3k,w=98 IOPS][eta 01m:59Jobs: 1 (f=1): [_(2),r(1),P(1)][36.8%][r=205MiB/s][r=52.5k IOPS][eta 01m:48s]               Jobs: 1 (f=0): [_(3),f(1)][100.0%][w=278MiB/s][w=71.0k IOPS][eta 00m:00s]                 
seq-read: (groupid=0, jobs=1): err= 0: pid=273989: Mon Jul  1 16:12:11 2024

brlin-tw

#!/bin/bash
# Steps:
# 1) Make sure bash is available
# 2) Create udev rule
# - path to new udev rule: /etc/udev/rules.d/50-x-resize.rules
# - udev rule content: 
# ACTION=="change",KERNEL=="card0", SUBSYSTEM=="drm", RUN+="/usr/local/bin/x-resize" 
# 3) Create /var/log/autores directory
# 4) Create script /usr/local/bin/x-resize (this file) and make executable
# 5) Reload udev rules with `sudo udevadm control --reload-rules`

brlin-tw

This gist is currenctly archived.

Please refer to previous revisions if you know what to do.

The patch proposed was merged into kernel in 5.8 release, but no longer working as of linux 5.11

Please contact me, if you have new info about workarounds for CSR Bluetooth Dongle.

Telegram:

brlin-tw

#!/bin/bash
exec {times}> times {typescript}> typescript < "${1-/dev/stdin}"
while read -r; do [[ $REPLY = '  "stdout": [' ]] && break; done # skip to this line
LANG=C
printf "Script started on %(%c)T\n" -1 >&"$typescript" # dummy
while read -r open; [[ $open = '[' ]]; do
  read -r elapsed; read -r string; read -r close
  eval printf %b%n "$string" characters >&"$typescript" # put count in $characters
  printf "%s %s\n" "${elapsed%,}" "$characters" >&"$times"
done

brlin-tw

Computer Information:
    Manufacturer:  Unknown
    Model:  Unknown
    Form Factor: Desktop
    No Touch Input Detected

Processor Information:
    CPU Vendor:  GenuineIntel
    CPU Brand:  Intel(R) Core(TM) i5-4460  CPU @ 3.20GHz
    CPU Family:  0x6

brlin-tw

Thread 1 "poedit" received signal SIGSEGV, Segmentation fault.
0x00007fa29b5c2192 in EVP_PBE_cleanup ()
   from target:/snap/poedit/8/gnome-platform/lib/x86_64-linux-gnu/libcrypto.so.1.0.0
#0  0x00007fa29b5c2192 in EVP_PBE_cleanup ()
   from target:/snap/poedit/8/gnome-platform/lib/x86_64-linux-gnu/libcrypto.so.1.0.0
#1  0x00007fa29b5bbe67 in EVP_cleanup ()
   from target:/snap/poedit/8/gnome-platform/lib/x86_64-linux-gnu/libcrypto.so.1.0.0
#2  0x0000000000816edc in boost::asio::ssl::detail::openssl_init_base::do_init::~do_init() ()
#3  0x000000000085ecf4 in std::_Sp_counted_ptr<boost::asio::ssl::detail::openssl_init_base::do_init*, (__gnu_cxx::_Lock_policy)2>::_M_dispose() ()
#4  0x00007fa29be87696 in std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release() ()

brlin-tw

#!/usr/bin/env bash

set -o errexit

if test "${USER}" != root; then
    echo You should run this program as root.
    exit 1
fi

if test -e /opt/Changingtec/CGServiSign; then

brlin-tw

14079 execve("/usr/lib/snapd/snap-confine", ["/usr/lib/snapd/snap-confine", "snap.guvcview-brlin.guvcview", "/usr/lib/snapd/snap-exec", "guvcview-brlin.guvcview"], [/* 102 vars */]) = 0
14079 brk(NULL)                         = 0x1265000
14079 fcntl(0, F_GETFD)                 = 0
14079 fcntl(1, F_GETFD)                 = 0
14079 fcntl(2, F_GETFD)                 = 0
14079 access("/etc/suid-debug", F_OK)   = -1 ENOENT (No such file or directory)
14079 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
14079 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
14079 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
14079 fstat(3, {st_mode=S_IFREG|0644, st_size=231591, ...}) = 0

brlin-tw

#!/usr/bin/env bash
declare -r APPLICATION_NAME='Clean Filter for GNU Bash Scripts'
# 林博仁 © 2017, 2018

# NOTE: ALWAYS PRINT MESSAGES TO STDERR as output to stdout will contaminate the input files when the program is operate in filter mode.

## Makes debuggers' life easier - Unofficial Bash Strict Mode
## BASHDOC: Shell Builtin Commands - Modifying Shell Behavior - The Set Builtin
set -o errexit
set -o errtrace