[PATCH 4.14 09/33] bpf: add also cbpf long jump test cases with heavy expansion

Greg Kroah-Hartman
2021-10-14T14:58:56Z

From: Daniel Borkmann <daniel@iogearbox.net>

commit be08815c5d3b25e53cd9b53a4d768d5f3d93ba25 upstream.

We have one triggering on eBPF but lets also add a cBPF example to
make sure we keep tracking them. Also add anther cBPF test running
max number of MSH ops.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
lib/test_bpf.c | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 63 insertions(+)

--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -355,6 +355,52 @@ static int bpf_fill_maxinsns11(struct bp
return __bpf_fill_ja(self, BPF_MAXINSNS, 68);
}

+static int bpf_fill_maxinsns12(struct bpf_test *self)
+{
+ unsigned int len = BPF_MAXINSNS;
+ struct sock_filter *insn;
+ int i = 0;
+
+ insn = kmalloc_array(len, sizeof(*insn), GFP_KERNEL);
+ if (!insn)
+ return -ENOMEM;
+
+ insn[0] = __BPF_JUMP(BPF_JMP | BPF_JA, len - 2, 0, 0);
+
+ for (i = 1; i < len - 1; i++)
+ insn[i] = __BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 0);
+
+ insn[len - 1] = __BPF_STMT(BPF_RET | BPF_K, 0xabababab);
+
+ self->u.ptr.insns = insn;
+ self->u.ptr.len = len;
+
+ return 0;
+}
+
+static int bpf_fill_maxinsns13(struct bpf_test *self)
+{
+ unsigned int len = BPF_MAXINSNS;
+ struct sock_filter *insn;
+ int i = 0;
+
+ insn = kmalloc_array(len, sizeof(*insn), GFP_KERNEL);
+ if (!insn)
+ return -ENOMEM;
+
+ for (i = 0; i < len - 3; i++)
+ insn[i] = __BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 0);
+
+ insn[len - 3] = __BPF_STMT(BPF_LD | BPF_IMM, 0xabababab);
+ insn[len - 2] = __BPF_STMT(BPF_ALU | BPF_XOR | BPF_X, 0);
+ insn[len - 1] = __BPF_STMT(BPF_RET | BPF_A, 0);
+
+ self->u.ptr.insns = insn;
+ self->u.ptr.len = len;
+
+ return 0;
+}
+
static int bpf_fill_ja(struct bpf_test *self)
{
/* Hits exactly 11 passes on x86_64 JIT. */
@@ -5438,6 +5484,23 @@ static struct bpf_test tests[] = {
.expected_errcode = -ENOTSUPP,
},
{
+ "BPF_MAXINSNS: jump over MSH",
+ { },
+ CLASSIC | FLAG_EXPECTED_FAIL,
+ { 0xfa, 0xfb, 0xfc, 0xfd, },
+ { { 4, 0xabababab } },
+ .fill_helper = bpf_fill_maxinsns12,
+ .expected_errcode = -EINVAL,
+ },
+ {
+ "BPF_MAXINSNS: exec all MSH",
+ { },
+ CLASSIC,
+ { 0xfa, 0xfb, 0xfc, 0xfd, },
+ { { 4, 0xababab83 } },
+ .fill_helper = bpf_fill_maxinsns13,
+ },
+ {
"BPF_MAXINSNS: ld_abs+get_processor_id",
{ },
CLASSIC,