You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
102 lines
2.3 KiB
102 lines
2.3 KiB
8 months ago
|
#!/bin/bash -eu
|
||
|
|
|
||
|
|
if [ $UID -ne 0 ]; then
|
||
|
|
echo "WARNING: This script needs to run as root to be effective"
|
||
|
|
exit 1
|
||
|
|
fi
|
||
|
|
|
||
|
|
export SYSTEMD_NSS_BYPASS_SYNTHETIC=1
|
||
|
|
|
||
|
|
if [ "${1:-}" = "--ignore-journal" ]; then
|
||
|
|
shift
|
||
|
|
ignore_journal=1
|
||
|
|
else
|
||
|
|
ignore_journal=0
|
||
|
|
fi
|
||
|
|
|
||
|
|
echo "Checking processes..."
|
||
|
|
if ps h -u 99 | grep .; then
|
||
|
|
echo "ERROR: ps reports processes with UID 99!"
|
||
|
|
exit 2
|
||
|
|
fi
|
||
|
|
echo "... not found"
|
||
|
|
|
||
|
|
echo "Checking UTMP..."
|
||
|
|
if w -h 199 | grep . ; then
|
||
|
|
echo "ERROR: w reports UID 99 as active!"
|
||
|
|
exit 2
|
||
|
|
fi
|
||
|
|
if w -h nobody | grep . ; then
|
||
|
|
echo "ERROR: w reports user nobody as active!"
|
||
|
|
exit 2
|
||
|
|
fi
|
||
|
|
echo "... not found"
|
||
|
|
|
||
|
|
echo "Checking the journal..."
|
||
|
|
if [ "$ignore_journal" = 0 ] && journalctl -q -b -n10 _UID=99 | grep . ; then
|
||
|
|
echo "ERROR: journalctl reports messages from UID 99 in current boot!"
|
||
|
|
exit 2
|
||
|
|
fi
|
||
|
|
echo "... not found"
|
||
|
|
|
||
|
|
echo "Looking for files in /etc, /run, /tmp, and /var..."
|
||
|
|
if find /etc /run /tmp /var -uid 99 -print | grep -m 10 . ; then
|
||
|
|
echo "ERROR: found files belonging to UID 99"
|
||
|
|
exit 2
|
||
|
|
fi
|
||
|
|
echo "... not found"
|
||
|
|
|
||
|
|
echo "Checking if nobody is defined correctly..."
|
||
|
|
if getent passwd nobody |
|
||
|
|
grep '^nobody:[x*]:65534:65534:.*:/:/sbin/nologin';
|
||
|
|
then
|
||
|
|
echo "OK, nothing to do."
|
||
|
|
exit 0
|
||
|
|
else
|
||
|
|
echo "NOTICE: User nobody is not defined correctly"
|
||
|
|
fi
|
||
|
|
|
||
|
|
echo "Checking if nfsnobody or something else is using the uid..."
|
||
|
|
if getent passwd 65534 | grep . ; then
|
||
|
|
echo "NOTICE: will have to remove this user"
|
||
|
|
else
|
||
|
|
echo "... not found"
|
||
|
|
fi
|
||
|
|
|
||
|
|
if [ "${1:-}" = "-x" ]; then
|
||
|
|
if getent passwd nobody >/dev/null; then
|
||
|
|
# this will remove both the user and the group.
|
||
|
|
( set -x
|
||
|
|
userdel nobody
|
||
|
|
)
|
||
|
|
fi
|
||
|
|
|
||
|
|
if getent passwd 65534 >/dev/null; then
|
||
|
|
# Make sure the uid is unused. This should free gid too.
|
||
|
|
name="$(getent passwd 65534 | cut -d: -f1)"
|
||
|
|
( set -x
|
||
|
|
userdel "$name"
|
||
|
|
)
|
||
|
|
fi
|
||
|
|
|
||
|
|
if grep -qE '^(passwd|group):.*\bsss\b' /etc/nsswitch.conf; then
|
||
|
|
echo "Sleeping, so sss can catch up"
|
||
|
|
sleep 3
|
||
|
|
fi
|
||
|
|
|
||
|
|
if getent group 65534; then
|
||
|
|
# Make sure the gid is unused, even if uid wasn't.
|
||
|
|
name="$(getent group 65534 | cut -d: -f1)"
|
||
|
|
( set -x
|
||
|
|
groupdel "$name"
|
||
|
|
)
|
||
|
|
fi
|
||
|
|
|
||
|
|
# systemd-sysusers uses the same gid and uid
|
||
|
|
( set -x
|
||
|
|
systemd-sysusers --inline 'u nobody 65534 "Kernel Overflow User" / /sbin/nologin'
|
||
|
|
)
|
||
|
|
else
|
||
|
|
echo "Pass '-x' to perform changes"
|
||
|
|
fi
|