diff options
| author | Fernando Fernandez Mancera <fmancera@suse.de> | 2026-09-22 21:18:52 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2026-09-30 09:35:20 +0200 |
| commit | 16d464013ec2267b00a83f4bfbb97b3ecc63bfa7 (patch) | |
| tree | ce9d95b768c66a02690575b48e04e949b15ca06a /net | |
| parent | 86b6471e690c67d4c5a1892993f34e080f1eae9d (diff) | |
netfilter: bpf: reject invalid NAT manipulation types
As bpf_ct_set_nat_info() is not validating the NAT manipulation type a
wrong value can be passed directly to nf_nat_setup_info(). This triggers
the WARN_ON() at nf_nat_setup_info() and if panic_on_warn isn't set,
then IPS_SRC_NAT_DONE is set without adding nat_bysource and conntrack
cleanup tries to unlink an uninitialized hlist node.
Fix this by checking that NAT manipulation type is correct before
calling nf_nat_setup_info(). In addition, if the WARN_ON is hit, return
NF_DROP instead of continuing with the processing to avoid similar
situations in the future.
Reported-by: VEGA <vega@nebusec.ai>
Fixes: 0fabd2aa199f ("net: netfilter: add bpf_ct_set_nat_info kfunc helper")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/nf_nat_bpf.c | 3 | ||||
| -rw-r--r-- | net/netfilter/nf_nat_core.c | 5 |
2 files changed, 6 insertions, 2 deletions
diff --git a/net/netfilter/nf_nat_bpf.c b/net/netfilter/nf_nat_bpf.c index f9dd85ccea01..7572b58c448b 100644 --- a/net/netfilter/nf_nat_bpf.c +++ b/net/netfilter/nf_nat_bpf.c @@ -39,6 +39,9 @@ __bpf_kfunc int bpf_ct_set_nat_info(struct nf_conn___init *nfct, if (proto != NFPROTO_IPV4 && proto != NFPROTO_IPV6) return -EINVAL; + if (manip != NF_NAT_MANIP_SRC && manip != NF_NAT_MANIP_DST) + return -EINVAL; + memset(&range, 0, sizeof(struct nf_nat_range2)); range.flags = NF_NAT_RANGE_MAP_IPS; range.min_addr = *addr; diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index a4858c2b2d65..cc8e1e81006d 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -767,8 +767,9 @@ nf_nat_setup_info(struct nf_conn *ct, if (nf_ct_is_confirmed(ct)) return NF_ACCEPT; - WARN_ON(maniptype != NF_NAT_MANIP_SRC && - maniptype != NF_NAT_MANIP_DST); + if (WARN_ON(maniptype != NF_NAT_MANIP_SRC && + maniptype != NF_NAT_MANIP_DST)) + return NF_DROP; if (WARN_ON(nf_nat_initialized(ct, maniptype))) return NF_DROP; |