selinux: convert range transition list to a hashtab
Per https://bugzilla.redhat.com/show_bug.cgi?id=548145
there are sufficient range transition rules in modern (Fedora) policy to
make mls_compute_sid a significant factor on the shmem file setup path
due to the length of the range_tr list. Replace the simple range_tr
list with a hashtab inside the security server to help mitigate this
problem.
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c
index e6654b5..443ae73 100644
--- a/security/selinux/ss/mls.c
+++ b/security/selinux/ss/mls.c
@@ -513,7 +513,8 @@
u32 specified,
struct context *newcontext)
{
- struct range_trans *rtr;
+ struct range_trans rtr;
+ struct mls_range *r;
if (!selinux_mls_enabled)
return 0;
@@ -521,15 +522,12 @@
switch (specified) {
case AVTAB_TRANSITION:
/* Look for a range transition rule. */
- for (rtr = policydb.range_tr; rtr; rtr = rtr->next) {
- if (rtr->source_type == scontext->type &&
- rtr->target_type == tcontext->type &&
- rtr->target_class == tclass) {
- /* Set the range from the rule */
- return mls_range_set(newcontext,
- &rtr->target_range);
- }
- }
+ rtr.source_type = scontext->type;
+ rtr.target_type = tcontext->type;
+ rtr.target_class = tclass;
+ r = hashtab_search(policydb.range_tr, &rtr);
+ if (r)
+ return mls_range_set(newcontext, r);
/* Fallthrough */
case AVTAB_CHANGE:
if (tclass == policydb.process_class)