1

llc: Constify struct llc_sap_state_trans

'struct llc_sap_state_trans' are not modified in this driver.

Constifying this structure moves some data to a read-only section, so
increase overall security.

On a x86_64, with allmodconfig, as an example:
Before:
======
   text	   data	    bss	    dec	    hex	filename
    339	    456	     24	    819	    333	net/llc/llc_s_st.o

After:
=====
   text	   data	    bss	    dec	    hex	filename
    683	    144	      0	    827	    33b	net/llc/llc_s_st.o

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/9d17587639195ee94b74ff06a11ef97d1833ee52.1720973710.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Christophe JAILLET 2024-07-14 18:15:20 +02:00 committed by Jakub Kicinski
parent 70de41ef78
commit 0970bf676f
3 changed files with 21 additions and 21 deletions

View File

@ -29,8 +29,8 @@ struct llc_sap_state_trans {
};
struct llc_sap_state {
u8 curr_state;
struct llc_sap_state_trans **transitions;
u8 curr_state;
const struct llc_sap_state_trans **transitions;
};
/* only access to SAP state table */

View File

@ -24,7 +24,7 @@
* last entry for this state
* all members are zeros, .bss zeroes it
*/
static struct llc_sap_state_trans llc_sap_state_trans_end;
static const struct llc_sap_state_trans llc_sap_state_trans_end;
/* state LLC_SAP_STATE_INACTIVE transition for
* LLC_SAP_EV_ACTIVATION_REQ event
@ -34,14 +34,14 @@ static const llc_sap_action_t llc_sap_inactive_state_actions_1[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_inactive_state_trans_1 = {
static const struct llc_sap_state_trans llc_sap_inactive_state_trans_1 = {
.ev = llc_sap_ev_activation_req,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_inactive_state_actions_1,
};
/* array of pointers; one to each transition */
static struct llc_sap_state_trans *llc_sap_inactive_state_transitions[] = {
static const struct llc_sap_state_trans *llc_sap_inactive_state_transitions[] = {
[0] = &llc_sap_inactive_state_trans_1,
[1] = &llc_sap_state_trans_end,
};
@ -52,7 +52,7 @@ static const llc_sap_action_t llc_sap_active_state_actions_1[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_1 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_1 = {
.ev = llc_sap_ev_rx_ui,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_active_state_actions_1,
@ -64,7 +64,7 @@ static const llc_sap_action_t llc_sap_active_state_actions_2[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_2 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_2 = {
.ev = llc_sap_ev_unitdata_req,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_active_state_actions_2,
@ -76,7 +76,7 @@ static const llc_sap_action_t llc_sap_active_state_actions_3[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_3 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_3 = {
.ev = llc_sap_ev_xid_req,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_active_state_actions_3,
@ -88,7 +88,7 @@ static const llc_sap_action_t llc_sap_active_state_actions_4[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_4 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_4 = {
.ev = llc_sap_ev_rx_xid_c,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_active_state_actions_4,
@ -100,7 +100,7 @@ static const llc_sap_action_t llc_sap_active_state_actions_5[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_5 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_5 = {
.ev = llc_sap_ev_rx_xid_r,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_active_state_actions_5,
@ -112,7 +112,7 @@ static const llc_sap_action_t llc_sap_active_state_actions_6[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_6 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_6 = {
.ev = llc_sap_ev_test_req,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_active_state_actions_6,
@ -124,7 +124,7 @@ static const llc_sap_action_t llc_sap_active_state_actions_7[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_7 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_7 = {
.ev = llc_sap_ev_rx_test_c,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_active_state_actions_7
@ -136,7 +136,7 @@ static const llc_sap_action_t llc_sap_active_state_actions_8[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_8 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_8 = {
.ev = llc_sap_ev_rx_test_r,
.next_state = LLC_SAP_STATE_ACTIVE,
.ev_actions = llc_sap_active_state_actions_8,
@ -150,14 +150,14 @@ static const llc_sap_action_t llc_sap_active_state_actions_9[] = {
[1] = NULL,
};
static struct llc_sap_state_trans llc_sap_active_state_trans_9 = {
static const struct llc_sap_state_trans llc_sap_active_state_trans_9 = {
.ev = llc_sap_ev_deactivation_req,
.next_state = LLC_SAP_STATE_INACTIVE,
.ev_actions = llc_sap_active_state_actions_9
};
/* array of pointers; one to each transition */
static struct llc_sap_state_trans *llc_sap_active_state_transitions[] = {
static const struct llc_sap_state_trans *llc_sap_active_state_transitions[] = {
[0] = &llc_sap_active_state_trans_2,
[1] = &llc_sap_active_state_trans_1,
[2] = &llc_sap_active_state_trans_3,

View File

@ -114,12 +114,12 @@ void llc_sap_rtn_pdu(struct llc_sap *sap, struct sk_buff *skb)
* Returns the pointer to found transition on success or %NULL for
* failure.
*/
static struct llc_sap_state_trans *llc_find_sap_trans(struct llc_sap *sap,
struct sk_buff *skb)
static const struct llc_sap_state_trans *llc_find_sap_trans(struct llc_sap *sap,
struct sk_buff *skb)
{
int i = 0;
struct llc_sap_state_trans *rc = NULL;
struct llc_sap_state_trans **next_trans;
const struct llc_sap_state_trans *rc = NULL;
const struct llc_sap_state_trans **next_trans;
struct llc_sap_state *curr_state = &llc_sap_state_table[sap->state - 1];
/*
* Search thru events for this state until list exhausted or until
@ -143,7 +143,7 @@ static struct llc_sap_state_trans *llc_find_sap_trans(struct llc_sap *sap,
* Returns 0 for success and 1 for failure of at least one action.
*/
static int llc_exec_sap_trans_actions(struct llc_sap *sap,
struct llc_sap_state_trans *trans,
const struct llc_sap_state_trans *trans,
struct sk_buff *skb)
{
int rc = 0;
@ -166,8 +166,8 @@ static int llc_exec_sap_trans_actions(struct llc_sap *sap,
*/
static int llc_sap_next_state(struct llc_sap *sap, struct sk_buff *skb)
{
const struct llc_sap_state_trans *trans;
int rc = 1;
struct llc_sap_state_trans *trans;
if (sap->state > LLC_NR_SAP_STATES)
goto out;