Question regarding sudo & crontab
I just created a script that is being run as a @reboot item in crontab -e.
It runs two scripts...in order. One creates ramdisks and populates them, and another runs an executable that depends on those ramdisks.
The first script looks like this:
#! /bin/bash
cd ~/trlserver/nginx
mkdir -p logs
sudo mount -t tmpfs -o size=1024M tmpfs logs
sudo chown $(whoami): logs
cd ~/trlserver/data
mkdir -p 20180927_na2018_ramdisk
sudo mount -t tmpfs -o size=5G tmpfs 20180927_na2018_ramdisk
sudo chown $(whoami): 20180927_na2018_ramdisk
cp -a 20180927_na2018/* 20180927_na2018_ramdisk
cp -a 20180927_na2018.additions/* 20180927_na2018_ramdisk
I've read the accepted answer here:
https://askubuntu.com/questions/173924/how-to-run-a-cron-job-using-the-sudo-command
Questions:
1) I could move this to be run separately (sudo crontab -e), and hardcode the user name, but how do I guarantee it would be executed before the script that depends on it?
2) What prevents an attacker from creating a cron job (crontab -e) that uses sudo set to run one minute from the current time...effectively bypassing password entry for use of sudo? (I tried this and it seemed to work)
sudo cron
asked 2 hours ago
zzxyzzzxyz
16410
add a comment |
I just created a script that is being run as a @reboot item in crontab -e.
It runs two scripts...in order. One creates ramdisks and populates them, and another runs an executable that depends on those ramdisks.
The first script looks like this:
#! /bin/bash
cd ~/trlserver/nginx
mkdir -p logs
sudo mount -t tmpfs -o size=1024M tmpfs logs
sudo chown $(whoami): logs
cd ~/trlserver/data
mkdir -p 20180927_na2018_ramdisk
sudo mount -t tmpfs -o size=5G tmpfs 20180927_na2018_ramdisk
sudo chown $(whoami): 20180927_na2018_ramdisk
cp -a 20180927_na2018/* 20180927_na2018_ramdisk
cp -a 20180927_na2018.additions/* 20180927_na2018_ramdisk
I've read the accepted answer here:
https://askubuntu.com/questions/173924/how-to-run-a-cron-job-using-the-sudo-command
Questions:
1) I could move this to be run separately (sudo crontab -e), and hardcode the user name, but how do I guarantee it would be executed before the script that depends on it?
2) What prevents an attacker from creating a cron job (crontab -e) that uses sudo set to run one minute from the current time...effectively bypassing password entry for use of sudo? (I tried this and it seemed to work)
sudo cron
asked 2 hours ago
zzxyzzzxyz
16410
add a comment |
I just created a script that is being run as a @reboot item in crontab -e.
It runs two scripts...in order. One creates ramdisks and populates them, and another runs an executable that depends on those ramdisks.
The first script looks like this:
#! /bin/bash
cd ~/trlserver/nginx
mkdir -p logs
sudo mount -t tmpfs -o size=1024M tmpfs logs
sudo chown $(whoami): logs
cd ~/trlserver/data
mkdir -p 20180927_na2018_ramdisk
sudo mount -t tmpfs -o size=5G tmpfs 20180927_na2018_ramdisk
sudo chown $(whoami): 20180927_na2018_ramdisk
cp -a 20180927_na2018/* 20180927_na2018_ramdisk
cp -a 20180927_na2018.additions/* 20180927_na2018_ramdisk
I've read the accepted answer here:
https://askubuntu.com/questions/173924/how-to-run-a-cron-job-using-the-sudo-command
Questions:
1) I could move this to be run separately (sudo crontab -e), and hardcode the user name, but how do I guarantee it would be executed before the script that depends on it?
2) What prevents an attacker from creating a cron job (crontab -e) that uses sudo set to run one minute from the current time...effectively bypassing password entry for use of sudo? (I tried this and it seemed to work)
sudo cron
asked 2 hours ago
zzxyzzzxyz
16410
I just created a script that is being run as a @reboot item in crontab -e.
It runs two scripts...in order. One creates ramdisks and populates them, and another runs an executable that depends on those ramdisks.
The first script looks like this:
#! /bin/bash
cd ~/trlserver/nginx
mkdir -p logs
sudo mount -t tmpfs -o size=1024M tmpfs logs
sudo chown $(whoami): logs
cd ~/trlserver/data
mkdir -p 20180927_na2018_ramdisk
sudo mount -t tmpfs -o size=5G tmpfs 20180927_na2018_ramdisk
sudo chown $(whoami): 20180927_na2018_ramdisk
cp -a 20180927_na2018/* 20180927_na2018_ramdisk
cp -a 20180927_na2018.additions/* 20180927_na2018_ramdisk
I've read the accepted answer here:
https://askubuntu.com/questions/173924/how-to-run-a-cron-job-using-the-sudo-command
Questions:
1) I could move this to be run separately (sudo crontab -e), and hardcode the user name, but how do I guarantee it would be executed before the script that depends on it?
2) What prevents an attacker from creating a cron job (crontab -e) that uses sudo set to run one minute from the current time...effectively bypassing password entry for use of sudo? (I tried this and it seemed to work)
sudo cron
sudo cron
asked 2 hours ago
zzxyzzzxyz
16410
asked 2 hours ago
zzxyzzzxyz
16410
asked 2 hours ago
zzxyzzzxyz
16410
asked 2 hours ago
zzxyzzzxyz
16410
asked 2 hours ago
zzxyzzzxyz
16410
16410
add a comment |
add a comment |
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