From 0970bf676f86c2c4d9bf7e672f5504d390c9fce6 Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Sun, 14 Jul 2024 18:15:20 +0200 Subject: [PATCH] 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 Reviewed-by: Simon Horman Link: https://patch.msgid.link/9d17587639195ee94b74ff06a11ef97d1833ee52.1720973710.git.christophe.jaillet@wanadoo.fr Signed-off-by: Jakub Kicinski --- 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;