mkstemp failing with RHEL 8 OS non-root user

Question

I have small script which creates a tmp files using mkstemp. My script was created using root user , but if I logged in as someother user other than root then my scripts runs but msktemp fails and says permission denied

sh: /tmp/tmpFile-khB5hH: Permission denied

Same thing while doing in RHEL 7 works and no Permission denied error, what is changed in RHEL 8. looks like RHEL 8 is checking logged on user vs effective user.

I tested this up in RHEL 7.5 and RHEL 8.4.

If someone know change in RHEL 8 which leads to permission problems please suggest. Thanks

What does ls -ld /tmp output? See also https://unix.stackexchange.com/questions/71622/what-are-correct-permissions-for-tmp-i-unintentionally-set-it-all-public-recu — Kusalananda, Aug 13 '21 at 17:12
@steve well problem is happening because my logged on user is different from the effective use ..hence it says permission denied which it should not do. mkstemp is able to create the temp file in /tmp when logged on user and my script user is same.....thought in RHEL7 it works fine — cjoshi, Aug 15 '21 at 11:53

score 0 · Answer 1 · answered Aug 17 '21 at 12:01

0

I have set the logged on user in my script by seteguid(getuid()) this work though it is dangerous. this make logged on user as always effective user and it doesnt fail on RHEL8.

answered Aug 17 '21 at 12:01

cjoshi

1

mkstemp failing with RHEL 8 OS non-root user

1 Answers1