[PATCH 2/2] ipv6: netfilter: Simplify NULL comparisons

From: Arushi Singhal
Date: Sat Apr 01 2017 - 12:13:43 EST

Remove instances of explicit NULL comparisons for code compaction.

Signed-off-by: Arushi Singhal <arushisinghal19971997@xxxxxxxxx>
---
net/ipv6/netfilter/ip6t_SYNPROXY.c | 16 ++++++++--------
net/ipv6/netfilter/ip6t_ipv6header.c | 2 +-
net/ipv6/netfilter/ip6table_filter.c | 2 +-
net/ipv6/netfilter/ip6table_mangle.c | 2 +-
net/ipv6/netfilter/ip6table_nat.c | 2 +-
net/ipv6/netfilter/ip6table_raw.c | 2 +-
net/ipv6/netfilter/ip6table_security.c | 2 +-
net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c | 2 +-
net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c | 4 ++--
net/ipv6/netfilter/nf_conntrack_reasm.c | 12 ++++++------
net/ipv6/netfilter/nf_dup_ipv6.c | 2 +-
net/ipv6/netfilter/nf_log_ipv6.c | 12 ++++++------
net/ipv6/netfilter/nf_reject_ipv6.c | 4 ++--
net/ipv6/netfilter/nf_socket_ipv6.c | 8 ++++----
net/ipv6/netfilter/nf_tables_ipv6.c | 2 +-
net/ipv6/netfilter/nft_dup_ipv6.c | 2 +-
16 files changed, 38 insertions(+), 38 deletions(-)

diff --git a/net/ipv6/netfilter/ip6t_SYNPROXY.c b/net/ipv6/netfilter/ip6t_SYNPROXY.c
index 4ef1ddd4bbbd..e0fa78085ad7 100644
--- a/net/ipv6/netfilter/ip6t_SYNPROXY.c
+++ b/net/ipv6/netfilter/ip6t_SYNPROXY.c
@@ -98,7 +98,7 @@ synproxy_send_client_synack(struct net *net,
tcp_hdr_size = sizeof(*nth) + synproxy_options_size(opts);
nskb = alloc_skb(sizeof(*niph) + tcp_hdr_size + MAX_TCP_HEADER,
GFP_ATOMIC);
- if (nskb == NULL)
+ if (!nskb)
return;
skb_reserve(nskb, MAX_TCP_HEADER);

@@ -140,7 +140,7 @@ synproxy_send_server_syn(struct net *net,
tcp_hdr_size = sizeof(*nth) + synproxy_options_size(opts);
nskb = alloc_skb(sizeof(*niph) + tcp_hdr_size + MAX_TCP_HEADER,
GFP_ATOMIC);
- if (nskb == NULL)
+ if (!nskb)
return;
skb_reserve(nskb, MAX_TCP_HEADER);

@@ -185,7 +185,7 @@ synproxy_send_server_ack(struct net *net,
tcp_hdr_size = sizeof(*nth) + synproxy_options_size(opts);
nskb = alloc_skb(sizeof(*niph) + tcp_hdr_size + MAX_TCP_HEADER,
GFP_ATOMIC);
- if (nskb == NULL)
+ if (!nskb)
return;
skb_reserve(nskb, MAX_TCP_HEADER);

@@ -223,7 +223,7 @@ synproxy_send_client_ack(struct net *net,
tcp_hdr_size = sizeof(*nth) + synproxy_options_size(opts);
nskb = alloc_skb(sizeof(*niph) + tcp_hdr_size + MAX_TCP_HEADER,
GFP_ATOMIC);
- if (nskb == NULL)
+ if (!nskb)
return;
skb_reserve(nskb, MAX_TCP_HEADER);

@@ -285,7 +285,7 @@ synproxy_tg6(struct sk_buff *skb, const struct xt_action_param *par)
return NF_DROP;

th = skb_header_pointer(skb, par->thoff, sizeof(_th), &_th);
- if (th == NULL)
+ if (!th)
return NF_DROP;

if (!synproxy_parse_options(skb, par->thoff, th, &opts))
@@ -335,11 +335,11 @@ static unsigned int ipv6_synproxy_hook(void *priv,
int thoff;

ct = nf_ct_get(skb, &ctinfo);
- if (ct == NULL)
+ if (!ct)
return NF_ACCEPT;

synproxy = nfct_synproxy(ct);
- if (synproxy == NULL)
+ if (!synproxy)
return NF_ACCEPT;

if (nf_is_loopback_packet(skb))
@@ -352,7 +352,7 @@ static unsigned int ipv6_synproxy_hook(void *priv,
return NF_ACCEPT;

th = skb_header_pointer(skb, thoff, sizeof(_th), &_th);
- if (th == NULL)
+ if (!th)
return NF_DROP;

state = &ct->proto.tcp;
diff --git a/net/ipv6/netfilter/ip6t_ipv6header.c b/net/ipv6/netfilter/ip6t_ipv6header.c
index 8b147440fbdc..c53ce6928130 100644
--- a/net/ipv6/netfilter/ip6t_ipv6header.c
+++ b/net/ipv6/netfilter/ip6t_ipv6header.c
@@ -65,7 +65,7 @@ ipv6header_mt6(const struct sk_buff *skb, struct xt_action_param *par)
}

hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
- BUG_ON(hp == NULL);
+ BUG_ON(!hp);

/* Calculate the header length */
if (nexthdr == NEXTHDR_FRAGMENT)
diff --git a/net/ipv6/netfilter/ip6table_filter.c b/net/ipv6/netfilter/ip6table_filter.c
index 1343077dde93..5c645fbf62ec 100644
--- a/net/ipv6/netfilter/ip6table_filter.c
+++ b/net/ipv6/netfilter/ip6table_filter.c
@@ -56,7 +56,7 @@ static int __net_init ip6table_filter_table_init(struct net *net)
return 0;

repl = ip6t_alloc_initial_table(&packet_filter);
- if (repl == NULL)
+ if (!repl)
return -ENOMEM;
/* Entry 1 is the FORWARD hook */
((struct ip6t_standard *)repl->entries)[1].target.verdict =
diff --git a/net/ipv6/netfilter/ip6table_mangle.c b/net/ipv6/netfilter/ip6table_mangle.c
index 2b1a9dcdbcb3..7d7ed25ff568 100644
--- a/net/ipv6/netfilter/ip6table_mangle.c
+++ b/net/ipv6/netfilter/ip6table_mangle.c
@@ -96,7 +96,7 @@ static int __net_init ip6table_mangle_table_init(struct net *net)
return 0;

repl = ip6t_alloc_initial_table(&packet_mangler);
- if (repl == NULL)
+ if (!repl)
return -ENOMEM;
ret = ip6t_register_table(net, &packet_mangler, repl, mangle_ops,
&net->ipv6.ip6table_mangle);
diff --git a/net/ipv6/netfilter/ip6table_nat.c b/net/ipv6/netfilter/ip6table_nat.c
index 7d2bd940291f..ec7f82a65a33 100644
--- a/net/ipv6/netfilter/ip6table_nat.c
+++ b/net/ipv6/netfilter/ip6table_nat.c
@@ -109,7 +109,7 @@ static int __net_init ip6table_nat_table_init(struct net *net)
return 0;

repl = ip6t_alloc_initial_table(&nf_nat_ipv6_table);
- if (repl == NULL)
+ if (!repl)
return -ENOMEM;
ret = ip6t_register_table(net, &nf_nat_ipv6_table, repl,
nf_nat_ipv6_ops, &net->ipv6.ip6table_nat);
diff --git a/net/ipv6/netfilter/ip6table_raw.c b/net/ipv6/netfilter/ip6table_raw.c
index d4bc56443dc1..39d61bc9f888 100644
--- a/net/ipv6/netfilter/ip6table_raw.c
+++ b/net/ipv6/netfilter/ip6table_raw.c
@@ -39,7 +39,7 @@ static int __net_init ip6table_raw_table_init(struct net *net)
return 0;

repl = ip6t_alloc_initial_table(&packet_raw);
- if (repl == NULL)
+ if (!repl)
return -ENOMEM;
ret = ip6t_register_table(net, &packet_raw, repl, rawtable_ops,
&net->ipv6.ip6table_raw);
diff --git a/net/ipv6/netfilter/ip6table_security.c b/net/ipv6/netfilter/ip6table_security.c
index cf26ccb04056..fad7d03e2553 100644
--- a/net/ipv6/netfilter/ip6table_security.c
+++ b/net/ipv6/netfilter/ip6table_security.c
@@ -56,7 +56,7 @@ static int __net_init ip6table_security_table_init(struct net *net)
return 0;

repl = ip6t_alloc_initial_table(&security_table);
- if (repl == NULL)
+ if (!repl)
return -ENOMEM;
ret = ip6t_register_table(net, &security_table, repl, sectbl_ops,
&net->ipv6.ip6table_security);
diff --git a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
index 4e3402486833..b88b98105c61 100644
--- a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
@@ -49,7 +49,7 @@ static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,

ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
sizeof(_addrs), _addrs);
- if (ap == NULL)
+ if (!ap)
return false;

memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
diff --git a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
index d2c2ccbfbe72..46892d085c25 100644
--- a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
@@ -43,7 +43,7 @@ static bool icmpv6_pkt_to_tuple(const struct sk_buff *skb,
struct icmp6hdr _hdr;

hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
- if (hp == NULL)
+ if (!hp)
return false;
tuple->dst.u.icmp.type = hp->icmp6_type;
tuple->src.u.icmp.id = hp->icmp6_identifier;
@@ -203,7 +203,7 @@ icmpv6_error(struct net *net, struct nf_conn *tmpl,
int type;

icmp6h = skb_header_pointer(skb, dataoff, sizeof(_ih), &_ih);
- if (icmp6h == NULL) {
+ if (!icmp6h) {
if (LOG_INVALID(net, IPPROTO_ICMPV6))
nf_log_packet(net, PF_INET6, 0, skb, NULL, NULL, NULL,
"nf_ct_icmpv6: short packet ");
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index 986d4ca38832..042bcbb11f00 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -102,7 +102,7 @@ static int nf_ct_frag6_sysctl_register(struct net *net)
if (!net_eq(net, &init_net)) {
table = kmemdup(table, sizeof(nf_ct_frag6_sysctl_table),
GFP_KERNEL);
- if (table == NULL)
+ if (!table)
goto err_alloc;

table[0].data = &net->nf_frag.frags.timeout;
@@ -114,7 +114,7 @@ static int nf_ct_frag6_sysctl_register(struct net *net)
}

hdr = register_net_sysctl(net, "net/netfilter", table);
- if (hdr == NULL)
+ if (!hdr)
goto err_reg;

net->nf_frag.sysctl.frags_hdr = hdr;
@@ -279,7 +279,7 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
goto err;

/* Point into the IP datagram 'data' part. */
- if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) {
+ if (!pskb_pull(skb, (u8 *)(fhdr + 1) - skb->data)) {
pr_debug("queue: message is too short.\n");
goto err;
}
@@ -379,7 +379,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct sk_buff *prev, struct net_devic

inet_frag_kill(&fq->q, &nf_frags);

- WARN_ON(head == NULL);
+ WARN_ON(!head);
WARN_ON(NFCT_FRAG6_CB(head)->offset != 0);

ecn = ip_frag_ecn_table[fq->ecn];
@@ -408,7 +408,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct sk_buff *prev, struct net_devic
int i, plen = 0;

clone = alloc_skb(0, GFP_ATOMIC);
- if (clone == NULL)
+ if (!clone)
return false;

clone->next = head->next;
@@ -592,7 +592,7 @@ int nf_ct_frag6_gather(struct net *net, struct sk_buff *skb, u32 user)
skb_orphan(skb);
fq = fq_find(net, fhdr->identification, user, &hdr->saddr, &hdr->daddr,
skb->dev ? skb->dev->ifindex : 0, ip6_frag_ecn(hdr));
- if (fq == NULL) {
+ if (!fq) {
pr_debug("Can't find and can't create new queue\n");
return -ENOMEM;
}
diff --git a/net/ipv6/netfilter/nf_dup_ipv6.c b/net/ipv6/netfilter/nf_dup_ipv6.c
index 888ecd106e5f..b77896b2a9bd 100644
--- a/net/ipv6/netfilter/nf_dup_ipv6.c
+++ b/net/ipv6/netfilter/nf_dup_ipv6.c
@@ -53,7 +53,7 @@ void nf_dup_ipv6(struct net *net, struct sk_buff *skb, unsigned int hooknum,
if (this_cpu_read(nf_skb_duplicated))
return;
skb = pskb_copy(skb, GFP_ATOMIC);
- if (skb == NULL)
+ if (!skb)
return;

#if IS_ENABLED(CONFIG_NF_CONNTRACK)
diff --git a/net/ipv6/netfilter/nf_log_ipv6.c b/net/ipv6/netfilter/nf_log_ipv6.c
index 97c724224da7..d8a88b81893b 100644
--- a/net/ipv6/netfilter/nf_log_ipv6.c
+++ b/net/ipv6/netfilter/nf_log_ipv6.c
@@ -55,7 +55,7 @@ static void dump_ipv6_packet(struct nf_log_buf *m,
logflags = NF_LOG_DEFAULT_MASK;

ih = skb_header_pointer(skb, ip6hoff, sizeof(_ip6h), &_ip6h);
- if (ih == NULL) {
+ if (!ih) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
@@ -78,7 +78,7 @@ static void dump_ipv6_packet(struct nf_log_buf *m,
const struct ipv6_opt_hdr *hp;

hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
- if (hp == NULL) {
+ if (!hp) {
nf_log_buf_add(m, "TRUNCATED");
return;
}
@@ -95,7 +95,7 @@ static void dump_ipv6_packet(struct nf_log_buf *m,
nf_log_buf_add(m, "FRAG:");
fh = skb_header_pointer(skb, ptr, sizeof(_fhdr),
&_fhdr);
- if (fh == NULL) {
+ if (!fh) {
nf_log_buf_add(m, "TRUNCATED ");
return;
}
@@ -143,7 +143,7 @@ static void dump_ipv6_packet(struct nf_log_buf *m,

ah = skb_header_pointer(skb, ptr, sizeof(_ahdr),
&_ahdr);
- if (ah == NULL) {
+ if (!ah) {
/*
* Max length: 26 "INCOMPLETE [65535
* bytes] )"
@@ -178,7 +178,7 @@ static void dump_ipv6_packet(struct nf_log_buf *m,
*/
eh = skb_header_pointer(skb, ptr, sizeof(_esph),
&_esph);
- if (eh == NULL) {
+ if (!eh) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
skb->len - ptr);
return;
@@ -224,7 +224,7 @@ static void dump_ipv6_packet(struct nf_log_buf *m,

/* Max length: 25 "INCOMPLETE [65535 bytes] " */
ic = skb_header_pointer(skb, ptr, sizeof(_icmp6h), &_icmp6h);
- if (ic == NULL) {
+ if (!ic) {
nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
skb->len - ptr);
return;
diff --git a/net/ipv6/netfilter/nf_reject_ipv6.c b/net/ipv6/netfilter/nf_reject_ipv6.c
index eedee5d108d9..c97ed15df5c2 100644
--- a/net/ipv6/netfilter/nf_reject_ipv6.c
+++ b/net/ipv6/netfilter/nf_reject_ipv6.c
@@ -44,7 +44,7 @@ const struct tcphdr *nf_reject_ip6_tcphdr_get(struct sk_buff *oldskb,

otcph = skb_header_pointer(oldskb, tcphoff, sizeof(struct tcphdr),
otcph);
- if (otcph == NULL)
+ if (!otcph)
return NULL;

/* No RST for RST. */
@@ -241,7 +241,7 @@ void nf_send_unreach6(struct net *net, struct sk_buff *skb_in,
if (!reject6_csum_ok(skb_in, hooknum))
return;

- if (hooknum == NF_INET_LOCAL_OUT && skb_in->dev == NULL)
+ if (hooknum == NF_INET_LOCAL_OUT && !skb_in->dev)
skb_in->dev = net->loopback_dev;

icmpv6_send(skb_in, ICMPV6_DEST_UNREACH, code, 0);
diff --git a/net/ipv6/netfilter/nf_socket_ipv6.c b/net/ipv6/netfilter/nf_socket_ipv6.c
index ebb2bf84232a..e7e85795edec 100644
--- a/net/ipv6/netfilter/nf_socket_ipv6.c
+++ b/net/ipv6/netfilter/nf_socket_ipv6.c
@@ -41,7 +41,7 @@ extract_icmp6_fields(const struct sk_buff *skb,

icmph = skb_header_pointer(skb, outside_hdrlen,
sizeof(_icmph), &_icmph);
- if (icmph == NULL)
+ if (!icmph)
return 1;

if (icmph->icmp6_type & ICMPV6_INFOMSG_MASK)
@@ -49,7 +49,7 @@ extract_icmp6_fields(const struct sk_buff *skb,

inside_iph = skb_header_pointer(skb, outside_hdrlen + sizeof(_icmph),
sizeof(*ipv6_var), ipv6_var);
- if (inside_iph == NULL)
+ if (!inside_iph)
return 1;
inside_nexthdr = inside_iph->nexthdr;

@@ -65,7 +65,7 @@ extract_icmp6_fields(const struct sk_buff *skb,

ports = skb_header_pointer(skb, inside_hdrlen,
sizeof(_ports), &_ports);
- if (ports == NULL)
+ if (!ports)
return 1;

/* the inside IP packet is the one quoted from our side, thus
@@ -119,7 +119,7 @@ struct sock *nf_sk_lookup_slow_v6(struct net *net, const struct sk_buff *skb,
struct udphdr _hdr, *hp;

hp = skb_header_pointer(skb, thoff, sizeof(_hdr), &_hdr);
- if (hp == NULL)
+ if (!hp)
return NULL;

saddr = &iph->saddr;
diff --git a/net/ipv6/netfilter/nf_tables_ipv6.c b/net/ipv6/netfilter/nf_tables_ipv6.c
index d6e4ba5de916..7a3d1b5017a1 100644
--- a/net/ipv6/netfilter/nf_tables_ipv6.c
+++ b/net/ipv6/netfilter/nf_tables_ipv6.c
@@ -59,7 +59,7 @@ EXPORT_SYMBOL_GPL(nft_af_ipv6);
static int nf_tables_ipv6_init_net(struct net *net)
{
net->nft.ipv6 = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
- if (net->nft.ipv6 == NULL)
+ if (!net->nft.ipv6)
return -ENOMEM;

memcpy(net->nft.ipv6, &nft_af_ipv6, sizeof(nft_af_ipv6));
diff --git a/net/ipv6/netfilter/nft_dup_ipv6.c b/net/ipv6/netfilter/nft_dup_ipv6.c
index d8b5b60b7d53..2badafe43db9 100644
--- a/net/ipv6/netfilter/nft_dup_ipv6.c
+++ b/net/ipv6/netfilter/nft_dup_ipv6.c
@@ -38,7 +38,7 @@ static int nft_dup_ipv6_init(const struct nft_ctx *ctx,
struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
int err;

- if (tb[NFTA_DUP_SREG_ADDR] == NULL)
+ if (!tb[NFTA_DUP_SREG_ADDR])
return -EINVAL;

priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]);
--
2.11.0