[PATCH] llc: Constify struct llc_sap_state_trans
From: Christophe JAILLET
Date: Sun Jul 14 2024 - 12:24:54 EST
'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@xxxxxxxxxx>
---
Compile tested-only.
---
include/net/llc_s_st.h | 4 ++--
net/llc/llc_s_st.c | 26 +++++++++++++-------------
net/llc/llc_sap.c | 12 ++++++------
3 files changed, 21 insertions(+), 21 deletions(-)
diff --git a/include/net/llc_s_st.h b/include/net/llc_s_st.h
index ed5b2fa40d32..fca49d483d20 100644
--- a/include/net/llc_s_st.h
+++ b/include/net/llc_s_st.h
@@ -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 */
diff --git a/net/llc/llc_s_st.c b/net/llc/llc_s_st.c
index 308c616883a4..acccc827c562 100644
--- a/net/llc/llc_s_st.c
+++ b/net/llc/llc_s_st.c
@@ -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,
diff --git a/net/llc/llc_sap.c b/net/llc/llc_sap.c
index 116c0e479183..6cd03c2ae7d5 100644
--- a/net/llc/llc_sap.c
+++ b/net/llc/llc_sap.c
@@ -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;
--
2.45.2