selftests/bpf: Check when bounds are not in the 32-bit range

Add cases to check if bound is updated correctly when 64-bit value is
not in the 32-bit range.

Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20230322213056.2470-2-daniel@iogearbox.net

diff --git a/tools/testing/selftests/bpf/verifier/bounds.c b/tools/testing/selftests/bpf/verifier/bounds.c
index 33125d5..74b1917 100644 (file)
--- a/tools/testing/selftests/bpf/verifier/bounds.c
+++ b/tools/testing/selftests/bpf/verifier/bounds.c
@@ -753,3 +753,124 @@
        .result_unpriv = REJECT,
        .result = ACCEPT,
 },
+{
+       "bound check with JMP_JLT for crossing 64-bit signed boundary",
+       .insns = {
+       BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+       BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+       BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+       BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 8),
+
+       BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+       BPF_LD_IMM64(BPF_REG_0, 0x7fffffffffffff10),
+       BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+       BPF_LD_IMM64(BPF_REG_0, 0x8000000000000000),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
+       /* r1 unsigned range is [0x7fffffffffffff10, 0x800000000000000f] */
+       BPF_JMP_REG(BPF_JLT, BPF_REG_0, BPF_REG_1, -2),
+
+       BPF_MOV64_IMM(BPF_REG_0, 0),
+       BPF_EXIT_INSN(),
+       },
+       .result = ACCEPT,
+       .prog_type = BPF_PROG_TYPE_XDP,
+},
+{
+       "bound check with JMP_JSLT for crossing 64-bit signed boundary",
+       .insns = {
+       BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+       BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+       BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+       BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 8),
+
+       BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+       BPF_LD_IMM64(BPF_REG_0, 0x7fffffffffffff10),
+       BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+       BPF_LD_IMM64(BPF_REG_0, 0x8000000000000000),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
+       /* r1 signed range is [S64_MIN, S64_MAX] */
+       BPF_JMP_REG(BPF_JSLT, BPF_REG_0, BPF_REG_1, -2),
+
+       BPF_MOV64_IMM(BPF_REG_0, 0),
+       BPF_EXIT_INSN(),
+       },
+       .errstr = "BPF program is too large",
+       .result = REJECT,
+       .prog_type = BPF_PROG_TYPE_XDP,
+},
+{
+       "bound check for loop upper bound greater than U32_MAX",
+       .insns = {
+       BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+       BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+       BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+       BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 8),
+
+       BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+       BPF_LD_IMM64(BPF_REG_0, 0x100000000),
+       BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+       BPF_LD_IMM64(BPF_REG_0, 0x100000000),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
+       BPF_JMP_REG(BPF_JLT, BPF_REG_0, BPF_REG_1, -2),
+
+       BPF_MOV64_IMM(BPF_REG_0, 0),
+       BPF_EXIT_INSN(),
+       },
+       .result = ACCEPT,
+       .prog_type = BPF_PROG_TYPE_XDP,
+},
+{
+       "bound check with JMP32_JLT for crossing 32-bit signed boundary",
+       .insns = {
+       BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+       BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+       BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+       BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 6),
+
+       BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+       BPF_MOV32_IMM(BPF_REG_0, 0x7fffff10),
+       BPF_ALU32_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+       BPF_MOV32_IMM(BPF_REG_0, 0x80000000),
+       BPF_ALU32_IMM(BPF_ADD, BPF_REG_0, 1),
+       /* r1 unsigned range is [0, 0x8000000f] */
+       BPF_JMP32_REG(BPF_JLT, BPF_REG_0, BPF_REG_1, -2),
+
+       BPF_MOV64_IMM(BPF_REG_0, 0),
+       BPF_EXIT_INSN(),
+       },
+       .result = ACCEPT,
+       .prog_type = BPF_PROG_TYPE_XDP,
+},
+{
+       "bound check with JMP32_JSLT for crossing 32-bit signed boundary",
+       .insns = {
+       BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+       BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+       BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+       BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 6),
+
+       BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+       BPF_MOV32_IMM(BPF_REG_0, 0x7fffff10),
+       BPF_ALU32_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+       BPF_MOV32_IMM(BPF_REG_0, 0x80000000),
+       BPF_ALU32_IMM(BPF_ADD, BPF_REG_0, 1),
+       /* r1 signed range is [S32_MIN, S32_MAX] */
+       BPF_JMP32_REG(BPF_JSLT, BPF_REG_0, BPF_REG_1, -2),
+
+       BPF_MOV64_IMM(BPF_REG_0, 0),
+       BPF_EXIT_INSN(),
+       },
+       .errstr = "BPF program is too large",
+       .result = REJECT,
+       .prog_type = BPF_PROG_TYPE_XDP,
+},