From 3f31e0d14d44ad491a81b7c1f83f32fbc300a867 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Mon, 16 Oct 2023 06:47:40 -0700 Subject: [PATCH] bpf: Add sockptr support for setsockopt The whole network stack uses sockptr, and while it doesn't move to something more modern, let's use sockptr in setsockptr BPF hooks, so, it could be used by other callers. The main motivation for this change is to use it in the io_uring {g,s}etsockopt(), which will use a userspace pointer for *optval, but, a kernel value for optlen. Link: https://lore.kernel.org/all/ZSArfLaaGcfd8LH8@gmail.com/ Signed-off-by: Breno Leitao Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/r/20231016134750.1381153-3-leitao@debian.org Signed-off-by: Jens Axboe --- include/linux/bpf-cgroup.h | 2 +- kernel/bpf/cgroup.c | 5 +++-- net/socket.c | 2 +- 3 files changed, 5 insertions(+), 4 deletions(-) diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index f5b4fb6ed8c67..cecfe8c99f280 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -137,7 +137,7 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head, enum cgroup_bpf_attach_type atype); int __cgroup_bpf_run_filter_setsockopt(struct sock *sock, int *level, - int *optname, char __user *optval, + int *optname, sockptr_t optval, int *optlen, char **kernel_optval); int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level, diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index ebc8c58f7e465..f0dedd4f7f2ea 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -1785,7 +1785,7 @@ static bool sockopt_buf_allocated(struct bpf_sockopt_kern *ctx, } int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level, - int *optname, char __user *optval, + int *optname, sockptr_t optval, int *optlen, char **kernel_optval) { struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data); @@ -1808,7 +1808,8 @@ int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level, ctx.optlen = *optlen; - if (copy_from_user(ctx.optval, optval, min(*optlen, max_optlen)) != 0) { + if (copy_from_sockptr(ctx.optval, optval, + min(*optlen, max_optlen))) { ret = -EFAULT; goto out; } diff --git a/net/socket.c b/net/socket.c index 82cd6890a4f0b..9a43f6e850c72 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2288,7 +2288,7 @@ int __sys_setsockopt(int fd, int level, int optname, char __user *user_optval, if (!in_compat_syscall()) err = BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock->sk, &level, &optname, - user_optval, &optlen, + optval, &optlen, &kernel_optval); if (err < 0) goto out_put; -- 2.30.2