#990962 /usr/bin/mkfifo: -Z leaks previous context into next directory without explicit label

Package:
coreutils
Source:
coreutils
Description:
GNU core utilities
Submitter:
наб
Date:
2021-07-11 19:27:05 UTC
Severity:
normal
#990962#5
Date:
2021-07-11 19:16:59 UTC
From:
To:
Dear Maintainer,

Consider the following case:
-- >8 --
# mkfifo -Z zupa
# mkfifo -Z /tmp/zupa
# ls -lZ zupa /tmp/zupa
prw-r--r--. 1 root root system_u:object_r:admin_home_t:s0   0 Jul 11 21:02 zupa
prw-r--r--. 1 root root unconfined_u:object_r:user_tmp_t:s0 0 Jul 11 21:02 /tmp/zupa
-- >8 --

Makes sense, as selinux_label(3) returns nothing for /tmp/zupa.

Now consider:
-- >8 --
# mkfifo -Z zupa /tmp/zupa
# ls -lZ zupa /tmp/zupa
prw-r--r--. 1 root root system_u:object_r:admin_home_t:s0 0 Jul 11 21:02 zupa
prw-r--r--. 1 root root system_u:object_r:admin_home_t:s0 0 Jul 11 21:02 /tmp/zupa
-- >8 --

As the kids say: oof, ouch, owie!