From 5ed17896a09e2cc3f07b7d8f6a8b1d6be54550f7 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Tue, 14 Oct 2025 23:54:57 +0000 Subject: [PATCH] bpf: Support bpf_setsockopt() for BPF_CGROUP_INET_SOCK_CREATE. We will support flagging sk->sk_bypass_prot_mem via bpf_setsockopt() at the BPF_CGROUP_INET_SOCK_CREATE hook. BPF_CGROUP_INET_SOCK_CREATE is invoked by __cgroup_bpf_run_filter_sk() that passes a pointer to struct sock to the bpf prog as void *ctx. But there are no bpf_func_proto for bpf_setsockopt() that receives the ctx as a pointer to struct sock. Also, bpf_getsockopt() will be necessary for a cgroup with multiple bpf progs running. Let's add new bpf_setsockopt() and bpf_getsockopt() variants for BPF_CGROUP_INET_SOCK_CREATE. Note that inet_create() is not under lock_sock() and has the same semantics with bpf_lsm_unlocked_sockopt_hooks. Signed-off-by: Kuniyuki Iwashima Signed-off-by: Martin KaFai Lau Acked-by: Roman Gushchin Link: https://patch.msgid.link/20251014235604.3057003-5-kuniyu@google.com --- net/core/filter.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/net/core/filter.c b/net/core/filter.c index 76628df1fc82f..ed3f0e5360595 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -5733,6 +5733,40 @@ static const struct bpf_func_proto bpf_sock_addr_getsockopt_proto = { .arg5_type = ARG_CONST_SIZE, }; +BPF_CALL_5(bpf_sock_create_setsockopt, struct sock *, sk, int, level, + int, optname, char *, optval, int, optlen) +{ + return __bpf_setsockopt(sk, level, optname, optval, optlen); +} + +static const struct bpf_func_proto bpf_sock_create_setsockopt_proto = { + .func = bpf_sock_create_setsockopt, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY, + .arg5_type = ARG_CONST_SIZE, +}; + +BPF_CALL_5(bpf_sock_create_getsockopt, struct sock *, sk, int, level, + int, optname, char *, optval, int, optlen) +{ + return __bpf_getsockopt(sk, level, optname, optval, optlen); +} + +static const struct bpf_func_proto bpf_sock_create_getsockopt_proto = { + .func = bpf_sock_create_getsockopt, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_UNINIT_MEM, + .arg5_type = ARG_CONST_SIZE, +}; + BPF_CALL_5(bpf_sock_ops_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, int, level, int, optname, char *, optval, int, optlen) { @@ -8062,6 +8096,20 @@ sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_sk_storage_get_cg_sock_proto; case BPF_FUNC_ktime_get_coarse_ns: return &bpf_ktime_get_coarse_ns_proto; + case BPF_FUNC_setsockopt: + switch (prog->expected_attach_type) { + case BPF_CGROUP_INET_SOCK_CREATE: + return &bpf_sock_create_setsockopt_proto; + default: + return NULL; + } + case BPF_FUNC_getsockopt: + switch (prog->expected_attach_type) { + case BPF_CGROUP_INET_SOCK_CREATE: + return &bpf_sock_create_getsockopt_proto; + default: + return NULL; + } default: return bpf_base_func_proto(func_id, prog); } -- 2.47.3