Commit bddaf9ad authored by Puranjay Mohan's avatar Puranjay Mohan Committed by Alexei Starovoitov
Browse files

bpf: net: netfilter: drop dead NULL checks 



bpf_xdp_ct_lookup() and bpf_skb_ct_lookup() receive bpf_tuple and opts
parameter that are expected to be not NULL for real usages (see doc
string above functions). They return an error if NULL is passed for opts
or tuple.

The verifier will now reject programs that pass NULL to these
parameters, the kfuns can assume that these are always valid pointer, so
drop the NULL checks for these parameters.

Signed-off-by: default avatarPuranjay Mohan <puranjay@kernel.org>
Link: https://lore.kernel.org/r/20260102180038.2708325-4-puranjay@kernel.org


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 7646c7af

net/netfilter/nf_conntrack_bpf.c

+4 −10
Original line number Diff line number Diff line
@@ -114,8 +114,6 @@ __bpf_nf_ct_alloc_entry(struct net *net, struct bpf_sock_tuple *bpf_tuple, 
	struct nf_conn *ct;

	int err;



	if (!opts || !bpf_tuple)

		return ERR_PTR(-EINVAL);

	if (!(opts_len == NF_BPF_CT_OPTS_SZ || opts_len == 12))

		return ERR_PTR(-EINVAL);

	if (opts_len == NF_BPF_CT_OPTS_SZ) {
@@ -299,7 +297,6 @@ bpf_xdp_ct_alloc(struct xdp_md *xdp_ctx, struct bpf_sock_tuple *bpf_tuple, 
	nfct = __bpf_nf_ct_alloc_entry(dev_net(ctx->rxq->dev), bpf_tuple, tuple__sz,

				       opts, opts__sz, 10);

	if (IS_ERR(nfct)) {

		if (opts)

		opts->error = PTR_ERR(nfct);

		return NULL;

	}
@@ -334,7 +331,6 @@ bpf_xdp_ct_lookup(struct xdp_md *xdp_ctx, struct bpf_sock_tuple *bpf_tuple, 
	caller_net = dev_net(ctx->rxq->dev);

	nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts, opts__sz);

	if (IS_ERR(nfct)) {

		if (opts)

		opts->error = PTR_ERR(nfct);

		return NULL;

	}
@@ -367,7 +363,6 @@ bpf_skb_ct_alloc(struct __sk_buff *skb_ctx, struct bpf_sock_tuple *bpf_tuple, 
	net = skb->dev ? dev_net(skb->dev) : sock_net(skb->sk);

	nfct = __bpf_nf_ct_alloc_entry(net, bpf_tuple, tuple__sz, opts, opts__sz, 10);

	if (IS_ERR(nfct)) {

		if (opts)

		opts->error = PTR_ERR(nfct);

		return NULL;

	}
@@ -402,7 +397,6 @@ bpf_skb_ct_lookup(struct __sk_buff *skb_ctx, struct bpf_sock_tuple *bpf_tuple, 
	caller_net = skb->dev ? dev_net(skb->dev) : sock_net(skb->sk);

	nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts, opts__sz);

	if (IS_ERR(nfct)) {

		if (opts)

		opts->error = PTR_ERR(nfct);

		return NULL;

	}