Is there an ideal chmod for /tmp (with /var/tmp symlinked to /tmp)?
I've seen people mention it both ways just curious as to the difference.
Is it a security difference?
on 02/08/2013 – Made popular on 02/08/2013
I'm "hacking" an ARM-base quadcopter running a stripped down Linux as part of a class assignment, and after getting into it using telnet and getting access to the bash terminal, and then messing around the file system I wanted to see what commands were available and how I could mess with it.
when I tried opening google-chrome in Ubuntu 12.04 LTS, I received the following error:
[1976:2032:299999600:ERROR:shared_memory_posix.cc(171)] Creating shared memory in /dev/shm/.com.google.Chrome.0ApmLo failed: No such file or directory
[1976:2032:299999742:ERROR:shared_memory_posix.cc(174)] Unable to access(W_OK|X_OK) /dev/shm: No such file or directory
You don't usually use mode= options with ext4 (and other Linux) filesystems. If you want these filesystems to have a specific mode or ownership, you have to mount them, and then set the ownerships with chmod / chown. In particular check that your /tmp/ filesystem was writable (chmod 1777 /tmp/.).Other than that there is nothing wrong with your fstab.
I noticed while answering another question that test and [ are different binaries, but the [ manpage pulls up test's. Besides the requirement for an ending ], is there any difference? If not, why are they separate binaries instead of being symlinked? (They are also bash builtins, and bash doesn't show a difference either.)