From: Florian Westphal <fw@strlen.de> stable inclusion from stable-v6.6.160 commit 7ce66bca55e37e2b8ad37e7990034ce6f5226fba category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/20692 CVE: CVE-2026-98490 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit c7f79f2620b7776586c626edf21eb6ed6ed3d1eb ] At this time, conntrack either returns NF_ACCEPT or NF_DROP. To improve debuging it would be nice to be able to replace NF_DROP verdict with NF_DROP_REASON() helper, This helper releases the skb instantly (so drop_monitor can pinpoint precise location) and returns NF_STOLEN. Prepare call sites to deal with this before introducing such changes in conntrack and nat core. Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Aaron Conole <aconole@redhat.om> Signed-off-by: David S. Miller <davem@davemloft.net> Stable-dep-of: 1a4151e6be57 ("net: openvswitch: conntrack: fix helper UAF due to extensions realloc") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Yi Yang <yiyang13@huawei.com> --- net/openvswitch/conntrack.c | 47 +++++++++++++++++++++++++++++-------- 1 file changed, 37 insertions(+), 10 deletions(-) diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c index f8b5cc9f9362..45b784efe059 100644 --- a/net/openvswitch/conntrack.c +++ b/net/openvswitch/conntrack.c @@ -679,6 +679,8 @@ static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, action |= BIT(NF_NAT_MANIP_DST); err = nf_ct_nat(skb, ct, ctinfo, &action, &info->range, info->commit); + if (err != NF_ACCEPT) + return err; if (action & BIT(NF_NAT_MANIP_SRC)) ovs_nat_update_key(key, skb, NF_NAT_MANIP_SRC); @@ -697,6 +699,22 @@ static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, } #endif +static int verdict_to_errno(unsigned int verdict) +{ + switch (verdict & NF_VERDICT_MASK) { + case NF_ACCEPT: + return 0; + case NF_DROP: + return -EINVAL; + case NF_STOLEN: + return -EINPROGRESS; + default: + break; + } + + return -EINVAL; +} + /* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if * not done already. Update key with new CT state after passing the packet * through conntrack. @@ -747,7 +765,7 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key, err = nf_conntrack_in(skb, &state); if (err != NF_ACCEPT) - return -ENOENT; + return verdict_to_errno(err); /* Clear CT state NAT flags to mark that we have not yet done * NAT after the nf_conntrack_in() call. We can actually clear @@ -774,9 +792,12 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key, * the key->ct_state. */ if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) && - (nf_ct_is_confirmed(ct) || info->commit) && - ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) { - return -EINVAL; + (nf_ct_is_confirmed(ct) || info->commit)) { + int err = ovs_ct_nat(net, key, info, skb, ct, ctinfo); + + err = verdict_to_errno(err); + if (err) + return err; } /* Userspace may decide to perform a ct lookup without a helper @@ -807,9 +828,12 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key, * - When committing an unconfirmed connection. */ if ((nf_ct_is_confirmed(ct) ? !cached || add_helper : - info->commit) && - nf_ct_helper(skb, ct, ctinfo, info->family) != NF_ACCEPT) { - return -EINVAL; + info->commit)) { + int err = nf_ct_helper(skb, ct, ctinfo, info->family); + + err = verdict_to_errno(err); + if (err) + return err; } if (nf_ct_protonum(ct) == IPPROTO_TCP && @@ -1017,10 +1041,9 @@ static int ovs_ct_commit(struct net *net, struct sw_flow_key *key, /* This will take care of sending queued events even if the connection * is already confirmed. */ - if (nf_conntrack_confirm(skb) != NF_ACCEPT) - return -EINVAL; + err = nf_conntrack_confirm(skb); - return 0; + return verdict_to_errno(err); } /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero @@ -1055,6 +1078,10 @@ int ovs_ct_execute(struct net *net, struct sk_buff *skb, else err = ovs_ct_lookup(net, key, info, skb); + /* conntrack core returned NF_STOLEN */ + if (err == -EINPROGRESS) + return err; + skb_push_rcsum(skb, nh_ofs); if (err) ovs_kfree_skb_reason(skb, OVS_DROP_CONNTRACK); -- 2.25.1