[PATCH] SELinux: audit task comm if exe cannot be determined

This patch ensures that the comm is included in the audit message if avc_audit
is unable to determine the exe due to the mmap_sem being held.  This is
helpful in tracking down the causes of permission denials that occur in the
mmap/mprotect hooks.
Signed-off-by: Stephen Smalley <sds@epoch.ncsc.mil>
Signed-off-by: James Morris <jmorris@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

security/selinux/avc.c

@@ -573,6 +573,8 @@ void avc_audit(u32 ssid, u32 tsid,
 					vma = vma->vm_next;
 				}
 				up_read(&mm->mmap_sem);
+			} else {
+				audit_log_format(ab, " comm=%s", tsk->comm);
 			}
 			if (tsk != current)
 				mmput(mm);