bpf: Change bpf_getsockopt(SOL_IP) to reuse do_ip_getsockopt()

This patch changes bpf_getsockopt(SOL_IP) to reuse
do_ip_getsockopt() and remove the duplicated code.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20220902002925.2895416-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/include/net/ip.h b/include/net/ip.h
index 34fa5b0..038097c 100644 (file)
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -747,6 +747,8 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
                     unsigned int optlen);
 int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
                  unsigned int optlen);
+int do_ip_getsockopt(struct sock *sk, int level, int optname,
+                    sockptr_t optval, sockptr_t optlen);
 int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
                  int __user *optlen);
 int ip_ra_control(struct sock *sk, unsigned char on,

diff --git a/net/core/filter.c b/net/core/filter.c
index beadd5b..3327546 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5166,23 +5166,29 @@ static int sol_tcp_sockopt(struct sock *sk, int optname,
                                 KERNEL_SOCKPTR(optval), *optlen);
 }
 
-static int sol_ip_setsockopt(struct sock *sk, int optname,
-                            char *optval, int optlen)
+static int sol_ip_sockopt(struct sock *sk, int optname,
+                         char *optval, int *optlen,
+                         bool getopt)
 {
        if (sk->sk_family != AF_INET)
                return -EINVAL;
 
        switch (optname) {
        case IP_TOS:
-               if (optlen != sizeof(int))
+               if (*optlen != sizeof(int))
                        return -EINVAL;
                break;
        default:
                return -EINVAL;
        }
 
+       if (getopt)
+               return do_ip_getsockopt(sk, SOL_IP, optname,
+                                       KERNEL_SOCKPTR(optval),
+                                       KERNEL_SOCKPTR(optlen));
+
        return do_ip_setsockopt(sk, SOL_IP, optname,
-                               KERNEL_SOCKPTR(optval), optlen);
+                               KERNEL_SOCKPTR(optval), *optlen);
 }
 
 static int sol_ipv6_setsockopt(struct sock *sk, int optname,
@@ -5214,7 +5220,7 @@ static int __bpf_setsockopt(struct sock *sk, int level, int optname,
        if (level == SOL_SOCKET)
                return sol_socket_sockopt(sk, optname, optval, &optlen, false);
        else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
-               return sol_ip_setsockopt(sk, optname, optval, optlen);
+               return sol_ip_sockopt(sk, optname, optval, &optlen, false);
        else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
                return sol_ipv6_setsockopt(sk, optname, optval, optlen);
        else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
@@ -5244,19 +5250,7 @@ static int __bpf_getsockopt(struct sock *sk, int level, int optname,
        } else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP) {
                err = sol_tcp_sockopt(sk, optname, optval, &optlen, true);
        } else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP) {
-               struct inet_sock *inet = inet_sk(sk);
-
-               if (optlen != sizeof(int) || sk->sk_family != AF_INET)
-                       goto err_clear;
-
-               /* Only some options are supported */
-               switch (optname) {
-               case IP_TOS:
-                       *((int *)optval) = (int)inet->tos;
-                       break;
-               default:
-                       goto err_clear;
-               }
+               err = sol_ip_sockopt(sk, optname, optval, &optlen, true);
        } else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6) {
                struct ipv6_pinfo *np = inet6_sk(sk);
 

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 5d134a7..47830f3 100644 (file)
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -1524,8 +1524,8 @@ static int compat_ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval,
        return 0;
 }
 
-static int do_ip_getsockopt(struct sock *sk, int level, int optname,
-                           sockptr_t optval, sockptr_t optlen)
+int do_ip_getsockopt(struct sock *sk, int level, int optname,
+                    sockptr_t optval, sockptr_t optlen)
 {
        struct inet_sock *inet = inet_sk(sk);
        bool needs_rtnl = getsockopt_needs_rtnl(optname);