From 546f109fdbbca75684f1041a1193cb910004a289 Mon Sep 17 00:00:00 2001 From: Xuanqiang Luo Date: Sat, 12 Sep 2026 21:40:40 +0800 Subject: [PATCH] ipv6: make IPV6_FREEBIND and IPV6_TRANSPARENT setsockopt lockless IPV6_FREEBIND and IPV6_TRANSPARENT still take the socket lock despite using inet_assign_bit() to update the flags shared with IP_FREEBIND and IP_TRANSPARENT. IPv6 TCP and UDP sockets can already update these flags without the lock through the corresponding SOL_IP options. Move both options to the lockless setsockopt path. Signed-off-by: Xuanqiang Luo Reviewed-by: Hangbin Liu Link: https://patch.msgid.link/20260912134040.215664-1-xuanqiang.luo@linux.dev Signed-off-by: Paolo Abeni --- net/ipv6/ipv6_sockglue.c | 36 +++++++++++++++--------------------- 1 file changed, 15 insertions(+), 21 deletions(-) diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 1f68fb64a43e..4b3536571c98 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -398,6 +398,21 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, /* Handle options that can be set without locking the socket. */ switch (optname) { + case IPV6_FREEBIND: + if (optlen < sizeof(int)) + return -EINVAL; + /* Shared with IP_FREEBIND. */ + inet_assign_bit(FREEBIND, sk, valbool); + return 0; + case IPV6_TRANSPARENT: + if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) && + !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) + return -EPERM; + if (optlen < sizeof(int)) + return -EINVAL; + /* Shared with IP_TRANSPARENT. */ + inet_assign_bit(TRANSPARENT, sk, valbool); + return 0; case IPV6_UNICAST_HOPS: if (optlen < sizeof(int)) return -EINVAL; @@ -666,27 +681,6 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, retv = 0; break; - case IPV6_TRANSPARENT: - if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) && - !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) { - retv = -EPERM; - break; - } - if (optlen < sizeof(int)) - goto e_inval; - /* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */ - inet_assign_bit(TRANSPARENT, sk, valbool); - retv = 0; - break; - - case IPV6_FREEBIND: - if (optlen < sizeof(int)) - goto e_inval; - /* we also don't have a separate freebind bit for IPV6 */ - inet_assign_bit(FREEBIND, sk, valbool); - retv = 0; - break; - case IPV6_RECVORIGDSTADDR: if (optlen < sizeof(int)) goto e_inval;