Currently the kernel audit system represents arch's as numbers and will
gladly accept comparisons between archs using >, <, >=, <= when the only
thing that makes sense is = or !=. I'm told that the next revision of
auditctl will do this checking but this will provide enforcement in the
kernel even for old userspace. A simple command to show the issue would
be to run
auditctl -d entry,always -F arch>i686 -S chmod
with this patch the kernel will reject this with -EINVAL
Please comment/ack/nak as soon as possible.
-Eric
kernel/auditfilter.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
--- linux-2.6.18.i686/kernel/auditfilter.c.audit.arch 2006-09-28 16:44:11.000000000 -0400
+++ linux-2.6.18.i686/kernel/auditfilter.c 2006-09-28 17:38:34.000000000 -0400
@@ -411,7 +411,6 @@ static struct audit_entry *audit_rule_to
case AUDIT_FSGID:
case AUDIT_LOGINUID:
case AUDIT_PERS:
- case AUDIT_ARCH:
case AUDIT_MSGTYPE:
case AUDIT_PPID:
case AUDIT_DEVMAJOR:
@@ -423,6 +422,14 @@ static struct audit_entry *audit_rule_to
case AUDIT_ARG2:
case AUDIT_ARG3:
break;
+ /* arch is only allowed to be = or != */
+ case AUDIT_ARCH:
+ if ((f->op != AUDIT_NOT_EQUAL) && (f->op != AUDIT_EQUAL)
+ && (f->op != AUDIT_NEGATE) && (f->op)) {
+ err = -EINVAL;
+ goto exit_free;
+ }
+ break;
case AUDIT_PERM:
if (f->val & ~15)
goto exit_free;