xfrm: state: add xfrm_state_deref_prot to state_by* walk under lock

We're under xfrm_state_lock for all those walks, we can use
xfrm_state_deref_prot to silence sparse warnings such as:

net/xfrm/xfrm_state.c:933:17: warning: dereference of noderef expression

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 34cf9f36168333751a7cbd01cdf6cd8d63c87c41..27192b11be43b24a251e44fb07ed31f54a6da97d 100644 (file)
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -870,7 +870,7 @@ xfrm_state_flush_secctx_check(struct net *net, u8 proto, bool task_valid)
        for (i = 0; i <= net->xfrm.state_hmask; i++) {
                struct xfrm_state *x;
 
-               hlist_for_each_entry(x, net->xfrm.state_bydst+i, bydst) {
+               hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + i, bydst) {
                        if (xfrm_id_proto_match(x->id.proto, proto) &&
                           (err = security_xfrm_state_delete(x)) != 0) {
                                xfrm_audit_state_delete(x, 0, task_valid);
@@ -891,7 +891,7 @@ xfrm_dev_state_flush_secctx_check(struct net *net, struct net_device *dev, bool
                struct xfrm_state *x;
                struct xfrm_dev_offload *xso;
 
-               hlist_for_each_entry(x, net->xfrm.state_bydst+i, bydst) {
+               hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + i, bydst) {
                        xso = &x->xso;
 
                        if (xso->dev == dev &&
@@ -931,7 +931,7 @@ int xfrm_state_flush(struct net *net, u8 proto, bool task_valid)
        for (i = 0; i <= net->xfrm.state_hmask; i++) {
                struct xfrm_state *x;
 restart:
-               hlist_for_each_entry(x, net->xfrm.state_bydst+i, bydst) {
+               hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + i, bydst) {
                        if (!xfrm_state_kern(x) &&
                            xfrm_id_proto_match(x->id.proto, proto)) {
                                xfrm_state_hold(x);
@@ -973,7 +973,7 @@ int xfrm_dev_state_flush(struct net *net, struct net_device *dev, bool task_vali
        err = -ESRCH;
        for (i = 0; i <= net->xfrm.state_hmask; i++) {
 restart:
-               hlist_for_each_entry(x, net->xfrm.state_bydst+i, bydst) {
+               hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + i, bydst) {
                        xso = &x->xso;
 
                        if (!xfrm_state_kern(x) && xso->dev == dev) {
@@ -1652,7 +1652,7 @@ xfrm_stateonly_find(struct net *net, u32 mark, u32 if_id,
 
        spin_lock_bh(&net->xfrm.xfrm_state_lock);
        h = xfrm_dst_hash(net, daddr, saddr, reqid, family);
-       hlist_for_each_entry(x, net->xfrm.state_bydst+h, bydst) {
+       hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + h, bydst) {
                if (x->props.family == family &&
                    x->props.reqid == reqid &&
                    (mark & x->mark.m) == x->mark.v &&
@@ -1779,7 +1779,7 @@ static void __xfrm_state_bump_genids(struct xfrm_state *xnew)
        u32 cpu_id = xnew->pcpu_num;
 
        h = xfrm_dst_hash(net, &xnew->id.daddr, &xnew->props.saddr, reqid, family);
-       hlist_for_each_entry(x, net->xfrm.state_bydst+h, bydst) {
+       hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + h, bydst) {
                if (x->props.family     == family &&
                    x->props.reqid      == reqid &&
                    x->if_id            == if_id &&
@@ -1815,7 +1815,7 @@ static struct xfrm_state *__find_acq_core(struct net *net,
        struct xfrm_state *x;
        u32 mark = m->v & m->m;
 
-       hlist_for_each_entry(x, net->xfrm.state_bydst+h, bydst) {
+       hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + h, bydst) {
                if (x->props.reqid  != reqid ||
                    x->props.mode   != mode ||
                    x->props.family != family ||
@@ -2097,7 +2097,7 @@ struct xfrm_state *xfrm_migrate_state_find(struct xfrm_migrate *m, struct net *n
        if (m->reqid) {
                h = xfrm_dst_hash(net, &m->old_daddr, &m->old_saddr,
                                  m->reqid, m->old_family);
-               hlist_for_each_entry(x, net->xfrm.state_bydst+h, bydst) {
+               hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + h, bydst) {
                        if (x->props.mode != m->mode ||
                            x->id.proto != m->proto)
                                continue;
@@ -2116,7 +2116,7 @@ struct xfrm_state *xfrm_migrate_state_find(struct xfrm_migrate *m, struct net *n
        } else {
                h = xfrm_src_hash(net, &m->old_daddr, &m->old_saddr,
                                  m->old_family);
-               hlist_for_each_entry(x, net->xfrm.state_bysrc+h, bysrc) {
+               hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bysrc, net) + h, bysrc) {
                        if (x->props.mode != m->mode ||
                            x->id.proto != m->proto)
                                continue;
@@ -2319,7 +2319,7 @@ void xfrm_state_update_stats(struct net *net)
 
        spin_lock_bh(&net->xfrm.xfrm_state_lock);
        for (i = 0; i <= net->xfrm.state_hmask; i++) {
-               hlist_for_each_entry(x, net->xfrm.state_bydst + i, bydst)
+               hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_bydst, net) + i, bydst)
                        xfrm_dev_state_update_stats(x);
        }
        spin_unlock_bh(&net->xfrm.xfrm_state_lock);
@@ -2510,7 +2510,7 @@ static struct xfrm_state *__xfrm_find_acq_byseq(struct net *net, u32 mark, u32 s
        unsigned int h = xfrm_seq_hash(net, seq);
        struct xfrm_state *x;
 
-       hlist_for_each_entry_rcu(x, net->xfrm.state_byseq + h, byseq) {
+       hlist_for_each_entry(x, xfrm_state_deref_prot(net->xfrm.state_byseq, net) + h, byseq) {
                if (x->km.seq == seq &&
                    (mark & x->mark.m) == x->mark.v &&
                    x->pcpu_num == pcpu_num &&