selinux: do not allocate ancillary buffer on first load

In security_load_policy(), we can defer allocating the newpolicydb
ancillary array to after checking state->initialized, thereby avoiding
the pointless allocation when loading policy the first time.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: merged portions by hand]
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This commit is contained in:
Ondrej Mosnacek 2020-01-16 13:04:34 +01:00 committed by Paul Moore
parent cb89e24658
commit dd89b9d9f3

View File

@ -2183,26 +2183,17 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len)
int rc = 0;
struct policy_file file = { data, len }, *fp = &file;
oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL);
if (!oldpolicydb) {
rc = -ENOMEM;
goto out;
}
newpolicydb = oldpolicydb + 1;
policydb = &state->ss->policydb;
newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL);
if (!newsidtab) {
rc = -ENOMEM;
goto out;
}
if (!newsidtab)
return -ENOMEM;
if (!selinux_initialized(state)) {
rc = policydb_read(policydb, fp);
if (rc) {
kfree(newsidtab);
goto out;
return rc;
}
policydb->len = len;
@ -2211,14 +2202,14 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len)
if (rc) {
kfree(newsidtab);
policydb_destroy(policydb);
goto out;
return rc;
}
rc = policydb_load_isids(policydb, newsidtab);
if (rc) {
kfree(newsidtab);
policydb_destroy(policydb);
goto out;
return rc;
}
state->ss->sidtab = newsidtab;
@ -2231,9 +2222,16 @@ int security_load_policy(struct selinux_state *state, void *data, size_t len)
selinux_status_update_policyload(state, seqno);
selinux_netlbl_cache_invalidate();
selinux_xfrm_notify_policyload();
goto out;
return 0;
}
oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL);
if (!oldpolicydb) {
kfree(newsidtab);
return -ENOMEM;
}
newpolicydb = oldpolicydb + 1;
rc = policydb_read(newpolicydb, fp);
if (rc) {
kfree(newsidtab);