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 <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Acked-by: John Fastabend <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

Author: Xu Kuohai

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,
+},