Merge branch 'fix-unconnected-udp'

Daniel Borkmann says:

====================
Please refer to the patch 1/6 as the main patch with the details
on the current sendmsg hook API limitations and proposal to fix
it in order to work with basic applications like DNS. Remaining
patches are the usual uapi and tooling updates as well as test
cases. Thanks a lot!

v2 -> v3:
  - Add attach types to test_section_names.c and libbpf (Andrey)
  - Added given Acks, rest as-is
v1 -> v2:
  - Split off uapi header sync and bpftool bits (Martin, Alexei)
  - Added missing bpftool doc and bash completion as well
====================

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

5 files changed, 15 insertions, 6 deletions

diff --git a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
index ac26876389c2..e744b3e4e56a 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst
@@ -29,7 +29,7 @@ CGROUP COMMANDS
 |	*PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* }
 |	*ATTACH_TYPE* := { **ingress** | **egress** | **sock_create** | **sock_ops** | **device** |
 |		**bind4** | **bind6** | **post_bind4** | **post_bind6** | **connect4** | **connect6** |
-|		**sendmsg4** | **sendmsg6** | **sysctl** }
+|		**sendmsg4** | **sendmsg6** | **recvmsg4** | **recvmsg6** | **sysctl** }
 |	*ATTACH_FLAGS* := { **multi** | **override** }
 
 DESCRIPTION
@@ -86,6 +86,10 @@ DESCRIPTION
 		  unconnected udp4 socket (since 4.18);
 		  **sendmsg6** call to sendto(2), sendmsg(2), sendmmsg(2) for an
 		  unconnected udp6 socket (since 4.18);
+		  **recvmsg4** call to recvfrom(2), recvmsg(2), recvmmsg(2) for
+                  an unconnected udp4 socket (since 5.2);
+		  **recvmsg6** call to recvfrom(2), recvmsg(2), recvmmsg(2) for
+                  an unconnected udp6 socket (since 5.2);
 		  **sysctl** sysctl access (since 5.2).
 
 	**bpftool cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG*
diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
index e8118544d118..018ecef8dc13 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
@@ -40,7 +40,7 @@ PROG COMMANDS
 |		**lwt_seg6local** | **sockops** | **sk_skb** | **sk_msg** | **lirc_mode2** |
 |		**cgroup/bind4** | **cgroup/bind6** | **cgroup/post_bind4** | **cgroup/post_bind6** |
 |		**cgroup/connect4** | **cgroup/connect6** | **cgroup/sendmsg4** | **cgroup/sendmsg6** |
-|		**cgroup/sysctl**
+|		**cgroup/recvmsg4** | **cgroup/recvmsg6** | **cgroup/sysctl**
 |	}
 |       *ATTACH_TYPE* := {
 |		**msg_verdict** | **stream_verdict** | **stream_parser** | **flow_dissector**
diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool
index 50e402a5a9c8..4300adf6e5ab 100644
--- a/tools/bpf/bpftool/bash-completion/bpftool
+++ b/tools/bpf/bpftool/bash-completion/bpftool
@@ -371,6 +371,7 @@ _bpftool()
                                 lirc_mode2 cgroup/bind4 cgroup/bind6 \
                                 cgroup/connect4 cgroup/connect6 \
                                 cgroup/sendmsg4 cgroup/sendmsg6 \
+                                cgroup/recvmsg4 cgroup/recvmsg6 \
                                 cgroup/post_bind4 cgroup/post_bind6 \
                                 cgroup/sysctl" -- \
                                                    "$cur" ) )
@@ -666,7 +667,7 @@ _bpftool()
                 attach|detach)
                     local ATTACH_TYPES='ingress egress sock_create sock_ops \
                         device bind4 bind6 post_bind4 post_bind6 connect4 \
-                        connect6 sendmsg4 sendmsg6 sysctl'
+                        connect6 sendmsg4 sendmsg6 recvmsg4 recvmsg6 sysctl'
                     local ATTACH_FLAGS='multi override'
                     local PROG_TYPE='id pinned tag'
                     case $prev in
@@ -676,7 +677,7 @@ _bpftool()
                             ;;
                         ingress|egress|sock_create|sock_ops|device|bind4|bind6|\
                         post_bind4|post_bind6|connect4|connect6|sendmsg4|\
-                        sendmsg6|sysctl)
+                        sendmsg6|recvmsg4|recvmsg6|sysctl)
                             COMPREPLY=( $( compgen -W "$PROG_TYPE" -- \
                                 "$cur" ) )
                             return 0
diff --git a/tools/bpf/bpftool/cgroup.c b/tools/bpf/bpftool/cgroup.c
index 7e22f115c8c1..73ec8ea33fb4 100644
--- a/tools/bpf/bpftool/cgroup.c
+++ b/tools/bpf/bpftool/cgroup.c
@@ -25,7 +25,8 @@
 	"       ATTACH_TYPE := { ingress | egress | sock_create |\n"	       \
 	"                        sock_ops | device | bind4 | bind6 |\n"	       \
 	"                        post_bind4 | post_bind6 | connect4 |\n"       \
-	"                        connect6 | sendmsg4 | sendmsg6 | sysctl }"
+	"                        connect6 | sendmsg4 | sendmsg6 |\n"           \
+	"                        recvmsg4 | recvmsg6 | sysctl }"
 
 static const char * const attach_type_strings[] = {
 	[BPF_CGROUP_INET_INGRESS] = "ingress",
@@ -42,6 +43,8 @@ static const char * const attach_type_strings[] = {
 	[BPF_CGROUP_UDP4_SENDMSG] = "sendmsg4",
 	[BPF_CGROUP_UDP6_SENDMSG] = "sendmsg6",
 	[BPF_CGROUP_SYSCTL] = "sysctl",
+	[BPF_CGROUP_UDP4_RECVMSG] = "recvmsg4",
+	[BPF_CGROUP_UDP6_RECVMSG] = "recvmsg6",
 	[__MAX_BPF_ATTACH_TYPE] = NULL,
 };
 
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 26336bad0442..7a4e21a31523 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -1063,7 +1063,8 @@ static int do_help(int argc, char **argv)
 		"                 sk_reuseport | flow_dissector | cgroup/sysctl |\n"
 		"                 cgroup/bind4 | cgroup/bind6 | cgroup/post_bind4 |\n"
 		"                 cgroup/post_bind6 | cgroup/connect4 | cgroup/connect6 |\n"
-		"                 cgroup/sendmsg4 | cgroup/sendmsg6 }\n"
+		"                 cgroup/sendmsg4 | cgroup/sendmsg6 | cgroup/recvmsg4 |\n"
+		"                 cgroup/recvmsg6 }\n"
 		"       ATTACH_TYPE := { msg_verdict | stream_verdict | stream_parser |\n"
 		"                        flow_dissector }\n"
 		"       " HELP_SPEC_OPTIONS "\n"