From: Simon Horman horms@kernel.org
[ Upstream commit fc56878ca1c288e49b5cbb43860a5938e3463654 ]
If CONFIG_BRIDGE_NETFILTER is not enabled, which is the case for x86_64 defconfig, then building nf_reject_ipv4.c and nf_reject_ipv6.c with W=1 using gcc-14 results in the following warnings, which are treated as errors:
net/ipv4/netfilter/nf_reject_ipv4.c: In function 'nf_send_reset': net/ipv4/netfilter/nf_reject_ipv4.c:243:23: error: variable 'niph' set but not used [-Werror=unused-but-set-variable] 243 | struct iphdr *niph; | ^~~~ cc1: all warnings being treated as errors net/ipv6/netfilter/nf_reject_ipv6.c: In function 'nf_send_reset6': net/ipv6/netfilter/nf_reject_ipv6.c:286:25: error: variable 'ip6h' set but not used [-Werror=unused-but-set-variable] 286 | struct ipv6hdr *ip6h; | ^~~~ cc1: all warnings being treated as errors
Address this by reducing the scope of these local variables to where they are used, which is code only compiled when CONFIG_BRIDGE_NETFILTER enabled.
Compile tested and run through netfilter selftests.
Reported-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Closes: https://lore.kernel.org/netfilter-devel/20240906145513.567781-1-andriy.shevc... Signed-off-by: Simon Horman horms@kernel.org Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/netfilter/nf_reject_ipv4.c | 10 ++++------ net/ipv6/netfilter/nf_reject_ipv6.c | 5 ++--- 2 files changed, 6 insertions(+), 9 deletions(-)
diff --git a/net/ipv4/netfilter/nf_reject_ipv4.c b/net/ipv4/netfilter/nf_reject_ipv4.c index 04504b2b51df5..87fd945a0d27a 100644 --- a/net/ipv4/netfilter/nf_reject_ipv4.c +++ b/net/ipv4/netfilter/nf_reject_ipv4.c @@ -239,9 +239,8 @@ static int nf_reject_fill_skb_dst(struct sk_buff *skb_in) void nf_send_reset(struct net *net, struct sock *sk, struct sk_buff *oldskb, int hook) { - struct sk_buff *nskb; - struct iphdr *niph; const struct tcphdr *oth; + struct sk_buff *nskb; struct tcphdr _oth;
oth = nf_reject_ip_tcphdr_get(oldskb, &_oth, hook); @@ -266,14 +265,12 @@ void nf_send_reset(struct net *net, struct sock *sk, struct sk_buff *oldskb, nskb->mark = IP4_REPLY_MARK(net, oldskb->mark);
skb_reserve(nskb, LL_MAX_HEADER); - niph = nf_reject_iphdr_put(nskb, oldskb, IPPROTO_TCP, - ip4_dst_hoplimit(skb_dst(nskb))); + nf_reject_iphdr_put(nskb, oldskb, IPPROTO_TCP, + ip4_dst_hoplimit(skb_dst(nskb))); nf_reject_ip_tcphdr_put(nskb, oldskb, oth); if (ip_route_me_harder(net, sk, nskb, RTN_UNSPEC)) goto free_nskb;
- niph = ip_hdr(nskb); - /* "Never happens" */ if (nskb->len > dst_mtu(skb_dst(nskb))) goto free_nskb; @@ -290,6 +287,7 @@ void nf_send_reset(struct net *net, struct sock *sk, struct sk_buff *oldskb, */ if (nf_bridge_info_exists(oldskb)) { struct ethhdr *oeth = eth_hdr(oldskb); + struct iphdr *niph = ip_hdr(nskb); struct net_device *br_indev;
br_indev = nf_bridge_get_physindev(oldskb, net); diff --git a/net/ipv6/netfilter/nf_reject_ipv6.c b/net/ipv6/netfilter/nf_reject_ipv6.c index dedee264b8f6c..69a78550261fb 100644 --- a/net/ipv6/netfilter/nf_reject_ipv6.c +++ b/net/ipv6/netfilter/nf_reject_ipv6.c @@ -283,7 +283,6 @@ void nf_send_reset6(struct net *net, struct sock *sk, struct sk_buff *oldskb, const struct tcphdr *otcph; unsigned int otcplen, hh_len; const struct ipv6hdr *oip6h = ipv6_hdr(oldskb); - struct ipv6hdr *ip6h; struct dst_entry *dst = NULL; struct flowi6 fl6;
@@ -339,8 +338,7 @@ void nf_send_reset6(struct net *net, struct sock *sk, struct sk_buff *oldskb, nskb->mark = fl6.flowi6_mark;
skb_reserve(nskb, hh_len + dst->header_len); - ip6h = nf_reject_ip6hdr_put(nskb, oldskb, IPPROTO_TCP, - ip6_dst_hoplimit(dst)); + nf_reject_ip6hdr_put(nskb, oldskb, IPPROTO_TCP, ip6_dst_hoplimit(dst)); nf_reject_ip6_tcphdr_put(nskb, oldskb, otcph, otcplen);
nf_ct_attach(nskb, oldskb); @@ -355,6 +353,7 @@ void nf_send_reset6(struct net *net, struct sock *sk, struct sk_buff *oldskb, */ if (nf_bridge_info_exists(oldskb)) { struct ethhdr *oeth = eth_hdr(oldskb); + struct ipv6hdr *ip6h = ipv6_hdr(nskb); struct net_device *br_indev;
br_indev = nf_bridge_get_physindev(oldskb, net);