Merge branch 'sockmap: add sockmap support for unix datagram socket'

Cong Wang says:

====================

From: Cong Wang <cong.wang@bytedance.com>

This is the last patchset of the original large patchset. In the
previous patchset, a new BPF sockmap program BPF_SK_SKB_VERDICT
was introduced and UDP began to support it too. In this patchset,
we add BPF_SK_SKB_VERDICT support to Unix datagram socket, so that
we can finally splice Unix datagram socket and UDP socket. Please
check each patch description for more details.

To see the big picture, the previous patchsets are available here:
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=1e0ab70778bd86a90de438cc5e1535c115a7c396
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=89d69c5d0fbcabd8656459bc8b1a476d6f1efee4

and this patchset is available here:
https://github.com/congwang/linux/tree/sockmap3
Acked-by: John Fastabend <john.fastabend@gmail.com>
---
v5: lift socket state check for dgram
    remove ->unhash() case
    add retries for EAGAIN in all test cases
    remove an unused parameter of __unix_dgram_recvmsg()
    rebase on the latest bpf-next

v4: fix af_unix disconnect case
    add unix_unhash()
    split out two small patches
    reduce u->iolock critical section
    remove an unused parameter of __unix_dgram_recvmsg()

v3: fix Kconfig dependency
    make unix_read_sock() static
    fix a UAF in unix_release()
    add a missing header unix_bpf.c

v2: separate out from the original large patchset
    rebase to the latest bpf-next
    clean up unix_read_sock()
    export sock_map_close()
    factor out some helpers in selftests for code reuse
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

2 files changed, 32 insertions, 18 deletions

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 94d77dc7ce35..d25c16c365e5 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1887,6 +1887,12 @@ void bpf_map_offload_map_free(struct bpf_map *map);
 int bpf_prog_test_run_syscall(struct bpf_prog *prog,
 			      const union bpf_attr *kattr,
 			      union bpf_attr __user *uattr);
+
+int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog);
+int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype);
+int sock_map_update_elem_sys(struct bpf_map *map, void *key, void *value, u64 flags);
+void sock_map_unhash(struct sock *sk);
+void sock_map_close(struct sock *sk, long timeout);
 #else
 static inline int bpf_prog_offload_init(struct bpf_prog *prog,
 					union bpf_attr *attr)
@@ -1919,24 +1925,6 @@ static inline int bpf_prog_test_run_syscall(struct bpf_prog *prog,
 {
 	return -ENOTSUPP;
 }
-#endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */
-
-#if defined(CONFIG_INET) && defined(CONFIG_BPF_SYSCALL)
-int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog);
-int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype);
-int sock_map_update_elem_sys(struct bpf_map *map, void *key, void *value, u64 flags);
-void sock_map_unhash(struct sock *sk);
-void sock_map_close(struct sock *sk, long timeout);
-
-void bpf_sk_reuseport_detach(struct sock *sk);
-int bpf_fd_reuseport_array_lookup_elem(struct bpf_map *map, void *key,
-				       void *value);
-int bpf_fd_reuseport_array_update_elem(struct bpf_map *map, void *key,
-				       void *value, u64 map_flags);
-#else
-static inline void bpf_sk_reuseport_detach(struct sock *sk)
-{
-}
 
 #ifdef CONFIG_BPF_SYSCALL
 static inline int sock_map_get_from_fd(const union bpf_attr *attr,
@@ -1956,7 +1944,21 @@ static inline int sock_map_update_elem_sys(struct bpf_map *map, void *key, void
 {
 	return -EOPNOTSUPP;
 }
+#endif /* CONFIG_BPF_SYSCALL */
+#endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */
 
+#if defined(CONFIG_INET) && defined(CONFIG_BPF_SYSCALL)
+void bpf_sk_reuseport_detach(struct sock *sk);
+int bpf_fd_reuseport_array_lookup_elem(struct bpf_map *map, void *key,
+				       void *value);
+int bpf_fd_reuseport_array_update_elem(struct bpf_map *map, void *key,
+				       void *value, u64 map_flags);
+#else
+static inline void bpf_sk_reuseport_detach(struct sock *sk)
+{
+}
+
+#ifdef CONFIG_BPF_SYSCALL
 static inline int bpf_fd_reuseport_array_lookup_elem(struct bpf_map *map,
 						     void *key, void *value)
 {
diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index f42fdddecd41..435a2c3d5a6f 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -82,6 +82,8 @@ static inline struct unix_sock *unix_sk(const struct sock *sk)
 long unix_inq_len(struct sock *sk);
 long unix_outq_len(struct sock *sk);
 
+int __unix_dgram_recvmsg(struct sock *sk, struct msghdr *msg, size_t size,
+			 int flags);
 #ifdef CONFIG_SYSCTL
 int unix_sysctl_register(struct net *net);
 void unix_sysctl_unregister(struct net *net);
@@ -89,4 +91,14 @@ void unix_sysctl_unregister(struct net *net);
 static inline int unix_sysctl_register(struct net *net) { return 0; }
 static inline void unix_sysctl_unregister(struct net *net) {}
 #endif
+
+#ifdef CONFIG_BPF_SYSCALL
+extern struct proto unix_proto;
+
+int unix_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
+void __init unix_bpf_build_proto(void);
+#else
+static inline void __init unix_bpf_build_proto(void)
+{}
+#endif
 #endif