From: Eric Dumazet edumazet@google.com

[ Upstream commit be69483bf4f3abaaca5d5ba460dbb50239463552 ]

Use BPF_REG_1 for source and destination of gso_segs read, to exercise "bpf: fix access to skb_shared_info->gso_segs" fix.

Signed-off-by: Eric Dumazet edumazet@google.com Suggested-by: Stanislav Fomichev sdf@google.com Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- tools/testing/selftests/bpf/verifier/ctx_skb.c | 11 +++++++++++ 1 file changed, 11 insertions(+)

diff --git a/tools/testing/selftests/bpf/verifier/ctx_skb.c b/tools/testing/selftests/bpf/verifier/ctx_skb.c index b0fda2877119c..d438193804b21 100644 --- a/tools/testing/selftests/bpf/verifier/ctx_skb.c +++ b/tools/testing/selftests/bpf/verifier/ctx_skb.c @@ -974,6 +974,17 @@ .result = ACCEPT, .prog_type = BPF_PROG_TYPE_CGROUP_SKB, }, +{ + "read gso_segs from CGROUP_SKB", + .insns = { + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, + offsetof(struct __sk_buff, gso_segs)), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .result = ACCEPT, + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, +}, { "write gso_segs from CGROUP_SKB", .insns = {