1 files changed, 43 insertions, 0 deletions

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index aa8812ae6776..9e9748089270 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -435,6 +435,41 @@ loop:
         return 0;
 }
 
+static int bpf_fill_ld_abs_vlan_push_pop2(struct bpf_test *self)
+{
+        struct bpf_insn *insn;
+
+        insn = kmalloc_array(16, sizeof(*insn), GFP_KERNEL);
+        if (!insn)
+                return -ENOMEM;
+
+        /* Due to func address being non-const, we need to
+         * assemble this here.
+         */
+        insn[0] = BPF_MOV64_REG(R6, R1);
+        insn[1] = BPF_LD_ABS(BPF_B, 0);
+        insn[2] = BPF_LD_ABS(BPF_H, 0);
+        insn[3] = BPF_LD_ABS(BPF_W, 0);
+        insn[4] = BPF_MOV64_REG(R7, R6);
+        insn[5] = BPF_MOV64_IMM(R6, 0);
+        insn[6] = BPF_MOV64_REG(R1, R7);
+        insn[7] = BPF_MOV64_IMM(R2, 1);
+        insn[8] = BPF_MOV64_IMM(R3, 2);
+        insn[9] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+                               bpf_skb_vlan_push_proto.func - __bpf_call_base);
+        insn[10] = BPF_MOV64_REG(R6, R7);
+        insn[11] = BPF_LD_ABS(BPF_B, 0);
+        insn[12] = BPF_LD_ABS(BPF_H, 0);
+        insn[13] = BPF_LD_ABS(BPF_W, 0);
+        insn[14] = BPF_MOV64_IMM(R0, 42);
+        insn[15] = BPF_EXIT_INSN();
+
+        self->u.ptr.insns = insn;
+        self->u.ptr.len = 16;
+
+        return 0;
+}
+
 static int bpf_fill_jump_around_ld_abs(struct bpf_test *self)
 {
         unsigned int len = BPF_MAXINSNS;
@@ -6066,6 +6101,14 @@ static struct bpf_test tests[] = {
                 {},
                 { {0x1, 0x42 } },
         },
+        {
+                "LD_ABS with helper changing skb data",
+                { },
+                INTERNAL,
+                { 0x34 },
+                { { ETH_HLEN, 42 } },
+                .fill_helper = bpf_fill_ld_abs_vlan_push_pop2,
+        },
 };
 
 static struct net_device dev;