[PATCH 2/5] netfilter: Clean up tests if NULL returned on failure

From: simran singhal
Date: Tue Mar 21 2017 - 04:45:09 EST


Some functions like kmalloc/kzalloc return NULL on failure. When NULL
represents failure, !x is commonly used.

This was done using Coccinelle:
@@
expression *e;
identifier l1;
@@
e = \(kmalloc\|kzalloc\|kcalloc\|devm_kzalloc\)(...);
...
- e == NULL
+ !e

Signed-off-by: simran singhal <singhalsimran0@xxxxxxxxx>
---

--This is my contribution to the netfilter project of
Outreachy Round 14.

net/netfilter/nf_conntrack_netlink.c | 2 +-
net/netfilter/nf_conntrack_proto.c | 2 +-
net/netfilter/nf_nat_core.c | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 6806b5e..cdcf4c1 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -779,7 +779,7 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[])
struct ctnetlink_filter *filter;

filter = kzalloc(sizeof(*filter), GFP_KERNEL);
- if (filter == NULL)
+ if (!filter)
return ERR_PTR(-ENOMEM);

filter->mark.val = ntohl(nla_get_be32(cda[CTA_MARK]));
diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c
index 2d6ee18..48d8354 100644
--- a/net/netfilter/nf_conntrack_proto.c
+++ b/net/netfilter/nf_conntrack_proto.c
@@ -358,7 +358,7 @@ int nf_ct_l4proto_register_one(struct nf_conntrack_l4proto *l4proto)
proto_array = kmalloc(MAX_NF_CT_PROTO *
sizeof(struct nf_conntrack_l4proto *),
GFP_KERNEL);
- if (proto_array == NULL) {
+ if (!proto_array) {
ret = -ENOMEM;
goto out_unlock;
}
diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
index 94b14c5..922bd5b 100644
--- a/net/netfilter/nf_nat_core.c
+++ b/net/netfilter/nf_nat_core.c
@@ -626,7 +626,7 @@ int nf_nat_l4proto_register(u8 l3proto, const struct nf_nat_l4proto *l4proto)
if (nf_nat_l4protos[l3proto] == NULL) {
l4protos = kmalloc(IPPROTO_MAX * sizeof(struct nf_nat_l4proto *),
GFP_KERNEL);
- if (l4protos == NULL) {
+ if (!l4protos) {
ret = -ENOMEM;
goto out;
}
--
2.7.4