audit: convert PPIDs to the inital PID namespace.
sys_getppid() returns the parent pid of the current process in its own pid
namespace. Since audit filters are based in the init pid namespace, a process
could avoid a filter or trigger an unintended one by being in an alternate pid
namespace or log meaningless information.
Switch to task_ppid_nr() for PPIDs to anchor all audit filters in the
init_pid_ns.
(informed by ebiederman's 6c621b7e)
Cc: stable@vger.kernel.org
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 57bf178..a6cf7ab 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -465,7 +465,7 @@
case AUDIT_PPID:
if (ctx) {
if (!ctx->ppid)
- ctx->ppid = sys_getppid();
+ ctx->ppid = task_ppid_nr(tsk);
result = audit_comparator(ctx->ppid, f->op, f->val);
}
break;
