From f99d7065a4d45529ccfdc630c1f278da805cf59f Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Tue, 30 Jun 2026 07:01:27 -0700 Subject: [PATCH] udp: convert udp_lib_getsockopt to sockopt_t In preparation for converting the proto-layer getsockopt callbacks to the sockopt_t interface, switch udp_lib_getsockopt() to take a sockopt_t. The thin udp_getsockopt()/udpv6_getsockopt() wrappers keep their __user signature for now: they build a user-backed sockopt_t with sockopt_init_user(), call the helper, and write the returned length back to optlen. The helper uses copy_to_iter() instead of copy_to_user(). No functional change. Signed-off-by: Breno Leitao Acked-by: Stanislav Fomichev Acked-by: Willem de Bruijn Link: https://patch.msgid.link/20260630-getsockopt_phase2-v2-2-193335f3d4d1@debian.org Signed-off-by: Paolo Abeni --- include/net/udp.h | 2 +- net/ipv4/udp.c | 39 +++++++++++++++++++++++++++++---------- net/ipv6/udp.c | 19 ++++++++++++++++--- 3 files changed, 46 insertions(+), 14 deletions(-) diff --git a/include/net/udp.h b/include/net/udp.h index 8262e2b215b4..1fee17274745 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -430,7 +430,7 @@ struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb, netdev_features_t features, bool is_ipv6); int udp_lib_getsockopt(struct sock *sk, int level, int optname, - char __user *optval, int __user *optlen); + sockopt_t *opt); int udp_lib_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen, int (*push_pending_frames)(struct sock *)); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 70f6cbd4ef73..59248a59358c 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -76,6 +76,7 @@ #include #include +#include #include #include #include @@ -2995,14 +2996,13 @@ static int udp_setsockopt(struct sock *sk, int level, int optname, sockptr_t opt } int udp_lib_getsockopt(struct sock *sk, int level, int optname, - char __user *optval, int __user *optlen) + sockopt_t *opt) { struct udp_sock *up = udp_sk(sk); int val, len; - if (get_user(len, optlen)) - return -EFAULT; - + len = opt->optlen; + /* keep the check so direct sockopt_t callers stay covered. */ if (len < 0) return -EINVAL; @@ -3037,9 +3037,8 @@ int udp_lib_getsockopt(struct sock *sk, int level, int optname, return -ENOPROTOOPT; } - if (put_user(len, optlen)) - return -EFAULT; - if (copy_to_user(optval, &val, len)) + opt->optlen = len; + if (copy_to_iter(&val, len, &opt->iter_out) != len) return -EFAULT; return 0; } @@ -3047,9 +3046,29 @@ int udp_lib_getsockopt(struct sock *sk, int level, int optname, static int udp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { - if (level == SOL_UDP) - return udp_lib_getsockopt(sk, level, optname, optval, optlen); - return ip_getsockopt(sk, level, optname, optval, optlen); + sockopt_t opt; + int err; + + /* + * keep the old __user pointers, until ip_getsockopt() moves + * to sockopt_t + */ + if (level != SOL_UDP) + return ip_getsockopt(sk, level, optname, optval, optlen); + + err = sockopt_init_user(&opt, optval, optlen); + if (err) + return err; + + err = udp_lib_getsockopt(sk, level, optname, &opt); + if (err) + return err; + + /* optval was written by copy_to_iter() in udp_lib_getsockopt() */ + if (put_user(opt.optlen, optlen)) + return -EFAULT; + + return 0; } /** diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 15e032194ecc..392e18b97045 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1826,9 +1826,22 @@ static int udpv6_setsockopt(struct sock *sk, int level, int optname, static int udpv6_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { - if (level == SOL_UDP) - return udp_lib_getsockopt(sk, level, optname, optval, optlen); - return ipv6_getsockopt(sk, level, optname, optval, optlen); + sockopt_t opt; + int err; + + if (level != SOL_UDP) + return ipv6_getsockopt(sk, level, optname, optval, optlen); + + err = sockopt_init_user(&opt, optval, optlen); + if (err) + return err; + + err = udp_lib_getsockopt(sk, level, optname, &opt); + if (err) + return err; + if (put_user(opt.optlen, optlen)) + return -EFAULT; + return 0; }