kernel/linux.git/net/ipv4, branch v6.1.168

tcp: Fix bind() regression for v6-only wildcard and v4-mapped-v6 non-wildcard addresses.

2026-04-11T12:16:18+00:00

commit ea111449501ea32bf6da82750de860243691efc7 upstream. Commit 5e07e672412b ("tcp: Use bhash2 for v4-mapped-v6 non-wildcard address.") introduced bind() regression for v4-mapped-v6 address. When we bind() the following two addresses on the same port, the 2nd bind() should succeed but fails now. 1. [::] w/ IPV6_ONLY 2. ::ffff:127.0.0.1 After the chagne, v4-mapped-v6 uses bhash2 instead of bhash to detect conflict faster, but I forgot to add a necessary change. During the 2nd bind(), inet_bind2_bucket_match_addr_any() returns the tb2 bucket of [::], and inet_bhash2_conflict() finally calls inet_bind_conflict(), which returns true, meaning conflict. inet_bhash2_addr_any_conflict |- inet_bind2_bucket_match_addr_any <-- return [::] bucket `- inet_bhash2_conflict `- __inet_bhash2_conflict <-- checks IPV6_ONLY for AF_INET | but not for v4-mapped-v6 address `- inet_bind_conflict <-- does not check address inet_bind_conflict() does not check socket addresses because __inet_bhash2_conflict() is expected to do so. However, it checks IPV6_V6ONLY attribute only against AF_INET socket, and not for v4-mapped-v6 address. As a result, v4-mapped-v6 address conflicts with v6-only wildcard address. To avoid that, let's add the missing test to use bhash2 for v4-mapped-v6 address. Fixes: 5e07e672412b ("tcp: Use bhash2 for v4-mapped-v6 non-wildcard address.") Signed-off-by: Kuniyuki Iwashima Link: https://lore.kernel.org/r/20240326204251.51301-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

udp: Fix wildcard bind conflict check when using hash2

2026-04-11T12:16:08+00:00

[ Upstream commit e537dd15d0d4ad989d56a1021290f0c674dd8b28 ] When binding a udp_sock to a local address and port, UDP uses two hashes (udptable->hash and udptable->hash2) for collision detection. The current code switches to "hash2" when hslot->count > 10. "hash2" is keyed by local address and local port. "hash" is keyed by local port only. The issue can be shown in the following bind sequence (pseudo code): bind(fd1, "[fd00::1]:8888") bind(fd2, "[fd00::2]:8888") bind(fd3, "[fd00::3]:8888") bind(fd4, "[fd00::4]:8888") bind(fd5, "[fd00::5]:8888") bind(fd6, "[fd00::6]:8888") bind(fd7, "[fd00::7]:8888") bind(fd8, "[fd00::8]:8888") bind(fd9, "[fd00::9]:8888") bind(fd10, "[fd00::10]:8888") /* Correctly return -EADDRINUSE because "hash" is used * instead of "hash2". udp_lib_lport_inuse() detects the * conflict. */ bind(fail_fd, "[::]:8888") /* After one more socket is bound to "[fd00::11]:8888", * hslot->count exceeds 10 and "hash2" is used instead. */ bind(fd11, "[fd00::11]:8888") bind(fail_fd, "[::]:8888") /* succeeds unexpectedly */ The same issue applies to the IPv4 wildcard address "0.0.0.0" and the IPv4-mapped wildcard address "::ffff:0.0.0.0". For example, if there are existing sockets bound to "192.168.1.[1-11]:8888", then binding "0.0.0.0:8888" or "[::ffff:0.0.0.0]:8888" can also miss the conflict when hslot->count > 10. TCP inet_csk_get_port() already has the correct check in inet_use_bhash2_on_bind(). Rename it to inet_use_hash2_on_bind() and move it to inet_hashtables.h so udp.c can reuse it in this fix. Fixes: 30fff9231fad ("udp: bind() optimisation") Reported-by: Andrew Onyshchuk Signed-off-by: Martin KaFai Lau Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260319181817.1901357-1-martin.lau@linux.dev Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

tcp: optimize inet_use_bhash2_on_bind()

2026-04-11T12:16:08+00:00

[ Upstream commit ca79d80b0b9f42362a893f06413a9fe91811158a ] There is no reason to call ipv6_addr_type(). Instead, use highly optimized ipv6_addr_any() and ipv6_addr_v4mapped(). Signed-off-by: Eric Dumazet Reviewed-by: Jason Xing Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250302124237.3913746-3-edumazet@google.com Signed-off-by: Jakub Kicinski Stable-dep-of: e537dd15d0d4 ("udp: Fix wildcard bind conflict check when using hash2") Signed-off-by: Sasha Levin

tcp: Rearrange tests in inet_csk_bind_conflict().

2026-04-11T12:16:08+00:00

[ Upstream commit 58655bc0ad7ccdd5b53319bcc091cb81b6aee7c3 ] The following patch adds code in the !inet_use_bhash2_on_bind(sk) case in inet_csk_bind_conflict(). To avoid adding nest and make the change cleaner, this patch rearranges tests in inet_csk_bind_conflict(). Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Stable-dep-of: e537dd15d0d4 ("udp: Fix wildcard bind conflict check when using hash2") Signed-off-by: Sasha Levin

tcp: Use bhash2 for v4-mapped-v6 non-wildcard address.

2026-04-11T12:16:08+00:00

[ Upstream commit 5e07e672412bed473122813ab35d4f7d42fd9635 ] While checking port availability in bind() or listen(), we used only bhash for all v4-mapped-v6 addresses. But there is no good reason not to use bhash2 for v4-mapped-v6 non-wildcard addresses. Let's do it by returning true in inet_use_bhash2_on_bind(). Then, we also need to add a test in inet_bind2_bucket_match_addr_any() so that ::ffff:X.X.X.X will match with 0.0.0.0. Note that sk->sk_rcv_saddr is initialised for v4-mapped-v6 sk in __inet6_bind(). Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Stable-dep-of: e537dd15d0d4 ("udp: Fix wildcard bind conflict check when using hash2") Signed-off-by: Sasha Levin

rtnetlink: pass netlink message header and portid to rtnl_configure_link()

2026-04-11T12:16:06+00:00

[ Upstream commit 1d997f1013079c05b642c739901e3584a3ae558d ] This patch pass netlink message header and portid to rtnl_configure_link() All the functions in this call chain need to add the parameters so we can use them in the last call rtnl_notify(), and notify the userspace about the new link info if NLM_F_ECHO flag is set. - rtnl_configure_link() - __dev_notify_flags() - rtmsg_ifinfo() - rtmsg_ifinfo_event() - rtmsg_ifinfo_build_skb() - rtmsg_ifinfo_send() - rtnl_notify() Also move __dev_notify_flags() declaration to net/core/dev.h, as Jakub suggested. Signed-off-by: Hangbin Liu Reviewed-by: Guillaume Nault Signed-off-by: Jakub Kicinski Stable-dep-of: 6931d21f87bc ("openvswitch: defer tunnel netdev_put to RCU release") Signed-off-by: Sasha Levin

esp: fix skb leak with espintcp and async crypto

2026-04-11T12:16:05+00:00

[ Upstream commit 0c0eef8ccd2413b0a10eb6bbd3442333b1e64dd2 ] When the TX queue for espintcp is full, esp_output_tail_tcp will return an error and not free the skb, because with synchronous crypto, the common xfrm output code will drop the packet for us. With async crypto (esp_output_done), we need to drop the skb when esp_output_tail_tcp returns an error. Fixes: e27cca96cd68 ("xfrm: add espintcp (RFC 8229)") Signed-off-by: Sabrina Dubroca Reviewed-by: Simon Horman Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin

xfrm: Fix the usage of skb->sk

2026-04-11T12:16:05+00:00

[ Upstream commit 1620c88887b16940e00dbe57dd38c74eda9bad9e ] xfrm assumed to always have a full socket at skb->sk. This is not always true, so fix it by converting to a full socket before it is used. Signed-off-by: Steffen Klassert Reviewed-by: Eric Dumazet Stable-dep-of: 0c0eef8ccd24 ("esp: fix skb leak with espintcp and async crypto") Signed-off-by: Sasha Levin

net: fix segmentation of forwarding fraglist GRO

2026-03-25T10:03:24+00:00

[ Upstream commit 426ca15c7f6cb6562a081341ca88893a50c59fa2 ] This patch enhances GSO segment handling by properly checking the SKB_GSO_DODGY flag for frag_list GSO packets, addressing low throughput issues observed when a station accesses IPv4 servers via hotspots with an IPv6-only upstream interface. Specifically, it fixes a bug in GSO segmentation when forwarding GRO packets containing a frag_list. The function skb_segment_list cannot correctly process GRO skbs that have been converted by XLAT, since XLAT only translates the header of the head skb. Consequently, skbs in the frag_list may remain untranslated, resulting in protocol inconsistencies and reduced throughput. To address this, the patch explicitly sets the SKB_GSO_DODGY flag for GSO packets in XLAT's IPv4/IPv6 protocol translation helpers (bpf_skb_proto_4_to_6 and bpf_skb_proto_6_to_4). This marks GSO packets as potentially modified after protocol translation. As a result, GSO segmentation will avoid using skb_segment_list and instead falls back to skb_segment for packets with the SKB_GSO_DODGY flag. This ensures that only safe and fully translated frag_list packets are processed by skb_segment_list, resolving protocol inconsistencies and improving throughput when forwarding GRO packets converted by XLAT. Signed-off-by: Jibin Zhang Fixes: 9fd1ff5d2ac7 ("udp: Support UDP fraglist GRO/GSO.") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260126152114.1211-1-jibin.zhang@mediatek.com Signed-off-by: Paolo Abeni Signed-off-by: Li hongliang <1468888505@139.com> Signed-off-by: Greg Kroah-Hartman

net: gso: fix tcp fraglist segmentation after pull from frag_list

2026-03-25T10:03:24+00:00

[ Upstream commit 17bd3bd82f9f79f3feba15476c2b2c95a9b11ff8 ] Detect tcp gso fraglist skbs with corrupted geometry (see below) and pass these to skb_segment instead of skb_segment_list, as the first can segment them correctly. Valid SKB_GSO_FRAGLIST skbs - consist of two or more segments - the head_skb holds the protocol headers plus first gso_size - one or more frag_list skbs hold exactly one segment - all but the last must be gso_size Optional datapath hooks such as NAT and BPF (bpf_skb_pull_data) can modify these skbs, breaking these invariants. In extreme cases they pull all data into skb linear. For TCP, this causes a NULL ptr deref in __tcpv4_gso_segment_list_csum at tcp_hdr(seg->next). Detect invalid geometry due to pull, by checking head_skb size. Don't just drop, as this may blackhole a destination. Convert to be able to pass to regular skb_segment. Approach and description based on a patch by Willem de Bruijn. Link: https://lore.kernel.org/netdev/20240428142913.18666-1-shiming.cheng@mediatek.com/ Link: https://lore.kernel.org/netdev/20240922150450.3873767-1-willemdebruijn.kernel@gmail.com/ Fixes: bee88cd5bd83 ("net: add support for segmenting TCP fraglist GSO packets") Cc: stable@vger.kernel.org Signed-off-by: Felix Fietkau Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20240926085315.51524-1-nbd@nbd.name Signed-off-by: Jakub Kicinski Signed-off-by: Li hongliang <1468888505@139.com> Signed-off-by: Greg Kroah-Hartman