From fef917ca6ba5d08b075dbc28de13ba4d1ffc2a9a Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Tue, 17 Apr 2012 16:26:54 -0400 Subject: [PATCH] fcaps: clear the same personality flags as suid when fcaps are used BugLink: http://bugs.launchpad.net/bugs/987337 commit d52fc5dde171f030170a6cb78034d166b13c9445 upstream. If a process increases permissions using fcaps all of the dangerous personality flags which are cleared for suid apps should also be cleared. Thus programs given priviledge with fcaps will continue to have address space randomization enabled even if the parent tried to disable it to make it easier to attack. Signed-off-by: Eric Paris Reviewed-by: Serge Hallyn Signed-off-by: James Morris Signed-off-by: Greg Kroah-Hartman Signed-off-by: Tim Gardner --- security/commoncap.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/security/commoncap.c b/security/commoncap.c index 09a5dbf..6693fe4 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -512,6 +512,11 @@ int cap_bprm_set_creds(struct linux_binprm *bprm) } skip: + /* if we have fs caps, clear dangerous personality flags */ + if (!cap_issubset(new->cap_permitted, old->cap_permitted)) + bprm->per_clear |= PER_CLEAR_ON_SETID; + + /* Don't let someone trace a set[ug]id/setpcap binary with the revised * credentials unless they have the appropriate permit. * -- 1.7.10.4