selftests/bpf: Calls bpf_setsockopt() on a ktls enabled socket.

Ensures that whenever bpf_setsockopt() is called with the SOL_TCP
option on a ktls enabled socket, the call will be accepted by the
system. The provided test makes sure of this by performing an
examination when the server side socket is in the CLOSE_WAIT state. At
this stage, ktls is still enabled on the server socket and can be used
to test if bpf_setsockopt() works correctly with linux.

Signed-off-by: Kui-Feng Lee <kuifeng@meta.com>
Link: https://lore.kernel.org/r/20230125201608.908230-3-kuifeng@meta.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

selftest/bpf: Add test for bpf_getsockopt()

This patch removes the __bpf_getsockopt() which directly
reads the sk by using PTR_TO_BTF_ID. Instead, the test now directly
uses the kernel bpf helper bpf_getsockopt() which supports all
the required optname now.

TCP_SAVE[D]_SYN and TCP_MAXSEG are not tested in a loop for all
the hooks and sock_ops's cb. TCP_SAVE[D]_SYN only works
in passive connection. TCP_MAXSEG only works when
it is setsockopt before the connection is established and
the getsockopt return value can only be tested after
the connection is established.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20220902002937.2896904-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftest/bpf: Ensure no module loading in bpf_setsockopt(TCP_CONGESTION)

This patch adds a test to ensure bpf_setsockopt(TCP_CONGESTION, "not_exist")
will not trigger the kernel module autoload.

Before the fix:

[ 40.535829] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274
[...]
[ 40.552134] tcp_ca_find_autoload.constprop.0+0xcb/0x200
[ 40.552689] tcp_set_congestion_control+0x99/0x7b0
[ 40.553203] do_tcp_setsockopt+0x3ed/0x2240
[...]
[ 40.556041] __bpf_setsockopt+0x124/0x640

Signed-off-by: Martin KaFai Lau <martin.lau@linux.dev>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220830231953.792412-1-martin.lau@linux.dev

selftests/bpf: Fix wrong size passed to bpf_setsockopt()

sizeof(new_cc) is not real memory size that new_cc points to; introduce
a new_cc_len to store the size and then pass it to bpf_setsockopt().

Fixes: 31123c0360e0 ("selftests/bpf: bpf_setsockopt tests")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220824013907.380448-1-yangyingliang@huawei.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

selftests/bpf: bpf_setsockopt tests

This patch adds tests to exercise optnames that are allowed
in bpf_setsockopt().

Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220817061847.4182339-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>