| Message ID | 1487498660-16600-4-git-send-email-hoeun.ryu@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2017/02/19 19:04, Hoeun Ryu wrote: > It would be good that selinux hooks objects are marked as > `__ro_mostly_after_init`. They can not be simply marked as `__ro_after_init' > because they should be writable during selinux_disable procedure. > `__ro_mostly_after_init` section is temporarily read-write during > selinux_disable procedure via set_ro_mostly_after_init_rw/ro pair. Now that > they can be read-only except during the procedure. > > -static struct security_hook_list selinux_hooks[] = { > +static struct security_hook_list selinux_hooks[] __ro_mostly_after_init = { This won't work. This variable is array of "struct list_head". You need to set same attribute to variables pointed by "struct list_head"->next and "struct list_head"->prev . > LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), > LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), > LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 9a8f12f..64fd799 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6106,7 +6106,7 @@ static int selinux_key_getsecurity(struct key *key, char **_buffer) #endif -static struct security_hook_list selinux_hooks[] = { +static struct security_hook_list selinux_hooks[] __ro_mostly_after_init = { LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), @@ -6381,7 +6381,7 @@ security_initcall(selinux_init); #if defined(CONFIG_NETFILTER) -static struct nf_hook_ops selinux_nf_ops[] = { +static struct nf_hook_ops selinux_nf_ops[] __ro_mostly_after_init = { { .hook = selinux_ipv4_postroute, .pf = NFPROTO_IPV4, @@ -6477,13 +6477,17 @@ int selinux_disable(void) selinux_disabled = 1; selinux_enabled = 0; + set_ro_mostly_after_init_rw(); security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); + set_ro_mostly_after_init_ro(); /* Try to destroy the avc node cache */ avc_disable(); /* Unregister netfilter hooks. */ + set_ro_mostly_after_init_ro(); selinux_nf_ip_exit(); + set_ro_mostly_after_init_rw(); /* Unregister selinuxfs. */ exit_sel_fs();
It would be good that selinux hooks objects are marked as `__ro_mostly_after_init`. They can not be simply marked as `__ro_after_init' because they should be writable during selinux_disable procedure. `__ro_mostly_after_init` section is temporarily read-write during selinux_disable procedure via set_ro_mostly_after_init_rw/ro pair. Now that they can be read-only except during the procedure. Signed-off-by: Hoeun Ryu <hoeun.ryu@gmail.com> --- security/selinux/hooks.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)