From 84967deee9d9870b15bc4c3acb50f1d401807902 Mon Sep 17 00:00:00 2001 From: Minhong He Date: Fri, 15 Aug 2025 14:38:45 +0800 Subject: ipv6: sr: validate HMAC algorithm ID in seg6_hmac_info_add The seg6_genl_sethmac() directly uses the algorithm ID provided by the userspace without verifying whether it is an HMAC algorithm supported by the system. If an unsupported HMAC algorithm ID is configured, packets using SRv6 HMAC will be dropped during encapsulation or decapsulation. Fixes: 4f4853dc1c9c ("ipv6: sr: implement API to control SR HMAC structure") Signed-off-by: Minhong He Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250815063845.85426-1-heminhong@kylinos.cn Signed-off-by: Jakub Kicinski --- net/ipv6/seg6_hmac.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'net/ipv6') diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c index f78ecb6ad838..d77b52523b6a 100644 --- a/net/ipv6/seg6_hmac.c +++ b/net/ipv6/seg6_hmac.c @@ -304,6 +304,9 @@ int seg6_hmac_info_add(struct net *net, u32 key, struct seg6_hmac_info *hinfo) struct seg6_pernet_data *sdata = seg6_pernet(net); int err; + if (!__hmac_get_algo(hinfo->alg_id)) + return -EINVAL; + err = rhashtable_lookup_insert_fast(&sdata->hmac_infos, &hinfo->node, rht_params); -- cgit v1.2.3 From a458b2902115b26a25d67393b12ddd57d1216aaa Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Mon, 18 Aug 2025 13:27:24 -0700 Subject: ipv6: sr: Fix MAC comparison to be constant-time To prevent timing attacks, MACs need to be compared in constant time. Use the appropriate helper function for this. Fixes: bf355b8d2c30 ("ipv6: sr: add core files for SR HMAC support") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Reviewed-by: Andrea Mayer Link: https://patch.msgid.link/20250818202724.15713-1-ebiggers@kernel.org Signed-off-by: Jakub Kicinski --- net/ipv6/seg6_hmac.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/ipv6') diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c index d77b52523b6a..fd58426f222b 100644 --- a/net/ipv6/seg6_hmac.c +++ b/net/ipv6/seg6_hmac.c @@ -35,6 +35,7 @@ #include #include +#include #include #include #include @@ -280,7 +281,7 @@ bool seg6_hmac_validate_skb(struct sk_buff *skb) if (seg6_hmac_compute(hinfo, srh, &ipv6_hdr(skb)->saddr, hmac_output)) return false; - if (memcmp(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN) != 0) + if (crypto_memneq(hmac_output, tlv->hmac, SEG6_HMAC_FIELD_LEN)) return false; return true; -- cgit v1.2.3 From 91a79b792204313153e1bdbbe5acbfc28903b3a5 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 20 Aug 2025 14:37:07 +0200 Subject: netfilter: nf_reject: don't leak dst refcount for loopback packets recent patches to add a WARN() when replacing skb dst entry found an old bug: WARNING: include/linux/skbuff.h:1165 skb_dst_check_unset include/linux/skbuff.h:1164 [inline] WARNING: include/linux/skbuff.h:1165 skb_dst_set include/linux/skbuff.h:1210 [inline] WARNING: include/linux/skbuff.h:1165 nf_reject_fill_skb_dst+0x2a4/0x330 net/ipv4/netfilter/nf_reject_ipv4.c:234 [..] Call Trace: nf_send_unreach+0x17b/0x6e0 net/ipv4/netfilter/nf_reject_ipv4.c:325 nft_reject_inet_eval+0x4bc/0x690 net/netfilter/nft_reject_inet.c:27 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] .. This is because blamed commit forgot about loopback packets. Such packets already have a dst_entry attached, even at PRE_ROUTING stage. Instead of checking hook just check if the skb already has a route attached to it. Fixes: f53b9b0bdc59 ("netfilter: introduce support for reject at prerouting stage") Signed-off-by: Florian Westphal Link: https://patch.msgid.link/20250820123707.10671-1-fw@strlen.de Signed-off-by: Jakub Kicinski --- net/ipv4/netfilter/nf_reject_ipv4.c | 6 ++---- net/ipv6/netfilter/nf_reject_ipv6.c | 5 ++--- 2 files changed, 4 insertions(+), 7 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv4/netfilter/nf_reject_ipv4.c b/net/ipv4/netfilter/nf_reject_ipv4.c index 87fd945a0d27..0d3cb2ba6fc8 100644 --- a/net/ipv4/netfilter/nf_reject_ipv4.c +++ b/net/ipv4/netfilter/nf_reject_ipv4.c @@ -247,8 +247,7 @@ void nf_send_reset(struct net *net, struct sock *sk, struct sk_buff *oldskb, if (!oth) return; - if ((hook == NF_INET_PRE_ROUTING || hook == NF_INET_INGRESS) && - nf_reject_fill_skb_dst(oldskb) < 0) + if (!skb_dst(oldskb) && nf_reject_fill_skb_dst(oldskb) < 0) return; if (skb_rtable(oldskb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) @@ -321,8 +320,7 @@ void nf_send_unreach(struct sk_buff *skb_in, int code, int hook) if (iph->frag_off & htons(IP_OFFSET)) return; - if ((hook == NF_INET_PRE_ROUTING || hook == NF_INET_INGRESS) && - nf_reject_fill_skb_dst(skb_in) < 0) + if (!skb_dst(skb_in) && nf_reject_fill_skb_dst(skb_in) < 0) return; if (skb_csum_unnecessary(skb_in) || diff --git a/net/ipv6/netfilter/nf_reject_ipv6.c b/net/ipv6/netfilter/nf_reject_ipv6.c index 838295fa32e3..cb2d38e80de9 100644 --- a/net/ipv6/netfilter/nf_reject_ipv6.c +++ b/net/ipv6/netfilter/nf_reject_ipv6.c @@ -293,7 +293,7 @@ void nf_send_reset6(struct net *net, struct sock *sk, struct sk_buff *oldskb, fl6.fl6_sport = otcph->dest; fl6.fl6_dport = otcph->source; - if (hook == NF_INET_PRE_ROUTING || hook == NF_INET_INGRESS) { + if (!skb_dst(oldskb)) { nf_ip6_route(net, &dst, flowi6_to_flowi(&fl6), false); if (!dst) return; @@ -397,8 +397,7 @@ void nf_send_unreach6(struct net *net, struct sk_buff *skb_in, if (hooknum == NF_INET_LOCAL_OUT && skb_in->dev == NULL) skb_in->dev = net->loopback_dev; - if ((hooknum == NF_INET_PRE_ROUTING || hooknum == NF_INET_INGRESS) && - nf_reject6_fill_skb_dst(skb_in) < 0) + if (!skb_dst(skb_in) && nf_reject6_fill_skb_dst(skb_in) < 0) return; icmpv6_send(skb_in, ICMPV6_DEST_UNREACH, code, 0); -- cgit v1.2.3