BUG/MEDIUM: remove supplementary groups when changing gid
Without it, haproxy will retain the group membership of root, which may
give more access than intended to the process. For example, haproxy would
still be in the wheel group on Fedora 18, as seen with :
# haproxy -f /etc/haproxy/haproxy.cfg
# ps a -o pid,user,group,command | grep hapr
3545 haproxy haproxy haproxy -f /etc/haproxy/haproxy.cfg
4356 root root grep --color=auto hapr
# grep Group /proc/3545/status
Groups: 0 1 2 3 4 6 10
# getent group wheel
wheel:x:10:root,misc
[WT: The issue has been investigated by independent security research team
and realized by itself not being able to allow security exploitation.
Additionally, dropping groups is not allowed to unprivileged users,
though this mode of deployment is quite common. Thus a warning is
emitted in this case to inform the user. The fix could be backported
into all supported versions as the issue has always been there. ]
2 files changed