netfilter: conntrack: make all extensions 8-byte alignned

Florian Westphal · ummakynes · commit bb62a765b1b5 · 2022-02-04T06:30:28.000+01:00
All extensions except one need 8 byte alignment, so just make that the
default.

Signed-off-by: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
diff --git a/include/net/netfilter/nf_conntrack_extend.h b/include/net/netfilter/nf_conntrack_extend.h
@@ -49,7 +49,7 @@ enum nf_ct_ext_id {
 struct nf_ct_ext {
 	u8 offset[NF_CT_EXT_NUM];
 	u8 len;
-	char data[];
+	char data[] __aligned(8);
 };
 
 static inline bool __nf_ct_ext_exist(const struct nf_ct_ext *ext, u8 id)
@@ -83,10 +83,7 @@ struct nf_ct_ext_type {
 	void (*destroy)(struct nf_conn *ct);
 
 	enum nf_ct_ext_id id;
-
-	/* Length and min alignment. */
 	u8 len;
-	u8 align;
 };
 
 int nf_ct_extend_register(const struct nf_ct_ext_type *type);
diff --git a/net/netfilter/nf_conntrack_acct.c b/net/netfilter/nf_conntrack_acct.c
@@ -24,7 +24,6 @@ MODULE_PARM_DESC(acct, "Enable connection tracking flow accounting.");
 
 static const struct nf_ct_ext_type acct_extend = {
 	.len	= sizeof(struct nf_conn_acct),
-	.align	= __alignof__(struct nf_conn_acct),
 	.id	= NF_CT_EXT_ACCT,
 };
 
diff --git a/net/netfilter/nf_conntrack_ecache.c b/net/netfilter/nf_conntrack_ecache.c
@@ -306,7 +306,6 @@ static int nf_ct_events __read_mostly = NF_CT_EVENTS_DEFAULT;
 
 static const struct nf_ct_ext_type event_extend = {
 	.len	= sizeof(struct nf_conntrack_ecache),
-	.align	= __alignof__(struct nf_conntrack_ecache),
 	.id	= NF_CT_EXT_ECACHE,
 };
 
diff --git a/net/netfilter/nf_conntrack_extend.c b/net/netfilter/nf_conntrack_extend.c
@@ -65,7 +65,7 @@ void *nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp)
 		return NULL;
 	}
 
-	newoff = ALIGN(oldlen, t->align);
+	newoff = ALIGN(oldlen, __alignof__(struct nf_ct_ext));
 	newlen = newoff + t->len;
 	rcu_read_unlock();
 
diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c
@@ -552,7 +552,6 @@ EXPORT_SYMBOL_GPL(nf_nat_helper_unregister);
 
 static const struct nf_ct_ext_type helper_extend = {
 	.len	= sizeof(struct nf_conn_help),
-	.align	= __alignof__(struct nf_conn_help),
 	.id	= NF_CT_EXT_HELPER,
 };
 
diff --git a/net/netfilter/nf_conntrack_labels.c b/net/netfilter/nf_conntrack_labels.c
@@ -81,7 +81,6 @@ EXPORT_SYMBOL_GPL(nf_connlabels_put);
 
 static const struct nf_ct_ext_type labels_extend = {
 	.len    = sizeof(struct nf_conn_labels),
-	.align  = __alignof__(struct nf_conn_labels),
 	.id     = NF_CT_EXT_LABELS,
 };
 
diff --git a/net/netfilter/nf_conntrack_seqadj.c b/net/netfilter/nf_conntrack_seqadj.c
@@ -235,7 +235,6 @@ EXPORT_SYMBOL_GPL(nf_ct_seq_offset);
 
 static const struct nf_ct_ext_type nf_ct_seqadj_extend = {
 	.len	= sizeof(struct nf_conn_seqadj),
-	.align	= __alignof__(struct nf_conn_seqadj),
 	.id	= NF_CT_EXT_SEQADJ,
 };
 
diff --git a/net/netfilter/nf_conntrack_timeout.c b/net/netfilter/nf_conntrack_timeout.c
@@ -137,7 +137,6 @@ EXPORT_SYMBOL_GPL(nf_ct_destroy_timeout);
 
 static const struct nf_ct_ext_type timeout_extend = {
 	.len	= sizeof(struct nf_conn_timeout),
-	.align	= __alignof__(struct nf_conn_timeout),
 	.id	= NF_CT_EXT_TIMEOUT,
 };
 
diff --git a/net/netfilter/nf_conntrack_timestamp.c b/net/netfilter/nf_conntrack_timestamp.c
@@ -21,7 +21,6 @@ MODULE_PARM_DESC(tstamp, "Enable connection tracking flow timestamping.");
 
 static const struct nf_ct_ext_type tstamp_extend = {
 	.len	= sizeof(struct nf_conn_tstamp),
-	.align	= __alignof__(struct nf_conn_tstamp),
 	.id	= NF_CT_EXT_TSTAMP,
 };
 
diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
@@ -877,7 +877,6 @@ static void nf_nat_cleanup_conntrack(struct nf_conn *ct)
 
 static struct nf_ct_ext_type nat_extend __read_mostly = {
 	.len		= sizeof(struct nf_conn_nat),
-	.align		= __alignof__(struct nf_conn_nat),
 	.destroy	= nf_nat_cleanup_conntrack,
 	.id		= NF_CT_EXT_NAT,
 };
diff --git a/net/netfilter/nf_synproxy_core.c b/net/netfilter/nf_synproxy_core.c
@@ -238,7 +238,6 @@ synproxy_tstamp_adjust(struct sk_buff *skb, unsigned int protoff,
 
 static struct nf_ct_ext_type nf_ct_synproxy_extend __read_mostly = {
 	.len		= sizeof(struct nf_conn_synproxy),
-	.align		= __alignof__(struct nf_conn_synproxy),
 	.id		= NF_CT_EXT_SYNPROXY,
 };
 
diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c
@@ -59,7 +59,6 @@ static const struct rhashtable_params zones_params = {
 
 static struct nf_ct_ext_type act_ct_extend __read_mostly = {
 	.len		= sizeof(struct nf_conn_act_ct_ext),
-	.align		= __alignof__(struct nf_conn_act_ct_ext),
 	.id		= NF_CT_EXT_ACT_CT,
 };
 

Original file line number	Diff line number	Diff line change
`@@ -65,7 +65,7 @@ void nf_ct_ext_add(struct nf_conn ct, enum nf_ct_ext_id id, gfp_t gfp)`
`65`	`65`	`return NULL;`
`66`	`66`	`}`
`67`	`67`
`68`		`- newoff = ALIGN(oldlen, t->align);`
	`68`	`+ newoff = ALIGN(oldlen, __alignof__(struct nf_ct_ext));`
`69`	`69`	`newlen = newoff + t->len;`
`70`	`70`	`rcu_read_unlock();`
`71`	`71`