Re: [PATCH 08/10] net: use new capable_any functionality

From: Kuniyuki Iwashima
Date: Fri Mar 15 2024 - 19:12:16 EST


From: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
Date: Fri, 15 Mar 2024 12:37:29 +0100
> Use the new added capable_any function in appropriate cases, where a
> task is required to have any of two capabilities.
>
> Add sock_ns_capable_any() wrapper similar to existing sock_ns_capable()
> one.
>
> Reorder CAP_SYS_ADMIN last.
>
> Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
> Reviewed-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> (ieee802154 portion)
> ---
> v4:
> - introduce sockopt_ns_capable_any()
> v3:
> - rename to capable_any()
> - make use of ns_capable_any
> ---
> include/net/sock.h | 1 +
> net/caif/caif_socket.c | 2 +-
> net/core/sock.c | 15 +++++++++------
> net/ieee802154/socket.c | 6 ++----
> net/ipv4/ip_sockglue.c | 5 +++--
> net/ipv6/ipv6_sockglue.c | 3 +--
> net/unix/af_unix.c | 2 +-
> 7 files changed, 18 insertions(+), 16 deletions(-)
>
> diff --git a/include/net/sock.h b/include/net/sock.h
> index b5e00702acc1..2e64a80c8fca 100644
> --- a/include/net/sock.h
> +++ b/include/net/sock.h
> @@ -1736,6 +1736,7 @@ static inline void unlock_sock_fast(struct sock *sk, bool slow)
> void sockopt_lock_sock(struct sock *sk);
> void sockopt_release_sock(struct sock *sk);
> bool sockopt_ns_capable(struct user_namespace *ns, int cap);
> +bool sockopt_ns_capable_any(struct user_namespace *ns, int cap1, int cap2);
> bool sockopt_capable(int cap);
>
> /* Used by processes to "lock" a socket state, so that
> diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
> index 039dfbd367c9..2d811037e378 100644
> --- a/net/caif/caif_socket.c
> +++ b/net/caif/caif_socket.c
> @@ -1026,7 +1026,7 @@ static int caif_create(struct net *net, struct socket *sock, int protocol,
> .usersize = sizeof_field(struct caifsock, conn_req.param)
> };
>
> - if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
> + if (!capable_any(CAP_NET_ADMIN, CAP_SYS_ADMIN))
> return -EPERM;
> /*
> * The sock->type specifies the socket type to use.
> diff --git a/net/core/sock.c b/net/core/sock.c
> index 43bf3818c19e..fa9edcc3e23d 100644
> --- a/net/core/sock.c
> +++ b/net/core/sock.c
> @@ -1077,6 +1077,12 @@ bool sockopt_ns_capable(struct user_namespace *ns, int cap)
> }
> EXPORT_SYMBOL(sockopt_ns_capable);
>
> +bool sockopt_ns_capable_any(struct user_namespace *ns, int cap1, int cap2)
> +{
> + return has_current_bpf_ctx() || ns_capable_any(ns, cap1, cap2);
> +}
> +EXPORT_SYMBOL(sockopt_ns_capable_any);
> +
> bool sockopt_capable(int cap)
> {
> return has_current_bpf_ctx() || capable(cap);
> @@ -1118,8 +1124,7 @@ int sk_setsockopt(struct sock *sk, int level, int optname,
> switch (optname) {
> case SO_PRIORITY:
> if ((val >= 0 && val <= 6) ||
> - sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
> - sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
> + sockopt_ns_capable_any(sock_net(sk)->user_ns, CAP_NET_RAW, CAP_NET_ADMIN)) {
> sock_set_priority(sk, val);
> return 0;
> }
> @@ -1422,8 +1427,7 @@ int sk_setsockopt(struct sock *sk, int level, int optname,
> break;
>
> case SO_MARK:
> - if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
> - !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
> + if (!sockopt_ns_capable_any(sock_net(sk)->user_ns, CAP_NET_RAW, CAP_NET_ADMIN)) {
> ret = -EPERM;
> break;
> }
> @@ -2813,8 +2817,7 @@ int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
>
> switch (cmsg->cmsg_type) {
> case SO_MARK:
> - if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
> - !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
> + if (!ns_capable_any(sock_net(sk)->user_ns, CAP_NET_RAW, CAP_NET_ADMIN))
> return -EPERM;
> if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
> return -EINVAL;
> diff --git a/net/ieee802154/socket.c b/net/ieee802154/socket.c
> index 990a83455dcf..42b3b12eb493 100644
> --- a/net/ieee802154/socket.c
> +++ b/net/ieee802154/socket.c
> @@ -902,8 +902,7 @@ static int dgram_setsockopt(struct sock *sk, int level, int optname,
> ro->want_lqi = !!val;
> break;
> case WPAN_SECURITY:
> - if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
> - !ns_capable(net->user_ns, CAP_NET_RAW)) {
> + if (!ns_capable_any(net->user_ns, CAP_NET_ADMIN, CAP_NET_RAW)) {

IIUC, should CAP_NET_RAW be tested first ?

Then, perhaps you should remove the Reviewed-by tag.


> err = -EPERM;
> break;
> }
> @@ -926,8 +925,7 @@ static int dgram_setsockopt(struct sock *sk, int level, int optname,
> }
> break;
> case WPAN_SECURITY_LEVEL:
> - if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
> - !ns_capable(net->user_ns, CAP_NET_RAW)) {
> + if (!ns_capable_any(net->user_ns, CAP_NET_ADMIN, CAP_NET_RAW)) {

Same here.

Thanks!


> err = -EPERM;
> break;
> }
> diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
> index cf377377b52d..5a1e5ee20ddd 100644
> --- a/net/ipv4/ip_sockglue.c
> +++ b/net/ipv4/ip_sockglue.c
> @@ -1008,8 +1008,9 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname,
> inet_assign_bit(MC_ALL, sk, val);
> return 0;
> case IP_TRANSPARENT:
> - if (!!val && !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
> - !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
> + if (!!val &&
> + !sockopt_ns_capable_any(sock_net(sk)->user_ns,
> + CAP_NET_RAW, CAP_NET_ADMIN))
> return -EPERM;
> if (optlen < 1)
> return -EINVAL;
> diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
> index d4c28ec1bc51..e46b11b5d3dd 100644
> --- a/net/ipv6/ipv6_sockglue.c
> +++ b/net/ipv6/ipv6_sockglue.c
> @@ -773,8 +773,7 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
> break;
>
> case IPV6_TRANSPARENT:
> - if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) &&
> - !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) {
> + if (valbool && !sockopt_ns_capable_any(net->user_ns, CAP_NET_RAW, CAP_NET_ADMIN)) {
> retv = -EPERM;
> break;
> }
> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
> index 5b41e2321209..acc36b2d25d7 100644
> --- a/net/unix/af_unix.c
> +++ b/net/unix/af_unix.c
> @@ -1783,7 +1783,7 @@ static inline bool too_many_unix_fds(struct task_struct *p)
> struct user_struct *user = current_user();
>
> if (unlikely(READ_ONCE(user->unix_inflight) > task_rlimit(p, RLIMIT_NOFILE)))
> - return !capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN);
> + return !capable_any(CAP_SYS_RESOURCE, CAP_SYS_ADMIN);
> return false;
> }
>
> --
> 2.43.0