xref: /openbmc/linux/tools/testing/selftests/bpf/verifier/bpf_st_mem.c (revision 9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e)
11a24af65SEduard Zingerman {
21a24af65SEduard Zingerman 	"BPF_ST_MEM stack imm non-zero",
31a24af65SEduard Zingerman 	.insns = {
41a24af65SEduard Zingerman 	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 42),
51a24af65SEduard Zingerman 	BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
61a24af65SEduard Zingerman 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, -42),
71a24af65SEduard Zingerman 	/* if value is tracked correctly R0 is zero */
81a24af65SEduard Zingerman 	BPF_EXIT_INSN(),
91a24af65SEduard Zingerman 	},
101a24af65SEduard Zingerman 	.result = ACCEPT,
111a24af65SEduard Zingerman 	/* Use prog type that requires return value in range [0, 1] */
121a24af65SEduard Zingerman 	.prog_type = BPF_PROG_TYPE_SK_LOOKUP,
131a24af65SEduard Zingerman 	.expected_attach_type = BPF_SK_LOOKUP,
141a24af65SEduard Zingerman 	.runs = -1,
151a24af65SEduard Zingerman },
161a24af65SEduard Zingerman {
171a24af65SEduard Zingerman 	"BPF_ST_MEM stack imm zero",
181a24af65SEduard Zingerman 	.insns = {
191a24af65SEduard Zingerman 	/* mark stack 0000 0000 */
201a24af65SEduard Zingerman 	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
211a24af65SEduard Zingerman 	/* read and sum a few bytes */
221a24af65SEduard Zingerman 	BPF_MOV64_IMM(BPF_REG_0, 0),
231a24af65SEduard Zingerman 	BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -8),
241a24af65SEduard Zingerman 	BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
251a24af65SEduard Zingerman 	BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -4),
261a24af65SEduard Zingerman 	BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
271a24af65SEduard Zingerman 	BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -1),
281a24af65SEduard Zingerman 	BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
291a24af65SEduard Zingerman 	/* if value is tracked correctly R0 is zero */
301a24af65SEduard Zingerman 	BPF_EXIT_INSN(),
311a24af65SEduard Zingerman 	},
321a24af65SEduard Zingerman 	.result = ACCEPT,
331a24af65SEduard Zingerman 	/* Use prog type that requires return value in range [0, 1] */
341a24af65SEduard Zingerman 	.prog_type = BPF_PROG_TYPE_SK_LOOKUP,
351a24af65SEduard Zingerman 	.expected_attach_type = BPF_SK_LOOKUP,
361a24af65SEduard Zingerman 	.runs = -1,
371a24af65SEduard Zingerman },
38*2a33c5a2SEduard Zingerman {
39*2a33c5a2SEduard Zingerman 	"BPF_ST_MEM stack imm zero, variable offset",
40*2a33c5a2SEduard Zingerman 	.insns = {
41*2a33c5a2SEduard Zingerman 	/* set fp[-16], fp[-24] to zeros */
42*2a33c5a2SEduard Zingerman 	BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, 0),
43*2a33c5a2SEduard Zingerman 	BPF_ST_MEM(BPF_DW, BPF_REG_10, -24, 0),
44*2a33c5a2SEduard Zingerman 	/* r0 = random value in range [-32, -15] */
45*2a33c5a2SEduard Zingerman 	BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
46*2a33c5a2SEduard Zingerman 	BPF_JMP_IMM(BPF_JLE, BPF_REG_0, 16, 2),
47*2a33c5a2SEduard Zingerman 	BPF_MOV64_IMM(BPF_REG_0, 0),
48*2a33c5a2SEduard Zingerman 	BPF_EXIT_INSN(),
49*2a33c5a2SEduard Zingerman 	BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 32),
50*2a33c5a2SEduard Zingerman 	/* fp[r0] = 0, make a variable offset write of zero,
51*2a33c5a2SEduard Zingerman 	 *             this should preserve zero marks on stack.
52*2a33c5a2SEduard Zingerman 	 */
53*2a33c5a2SEduard Zingerman 	BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_10),
54*2a33c5a2SEduard Zingerman 	BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
55*2a33c5a2SEduard Zingerman 	/* r0 = fp[-20], if variable offset write was tracked correctly
56*2a33c5a2SEduard Zingerman 	 *               r0 would be a known zero.
57*2a33c5a2SEduard Zingerman 	 */
58*2a33c5a2SEduard Zingerman 	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_10, -20),
59*2a33c5a2SEduard Zingerman 	/* Would fail return code verification if r0 range is not tracked correctly. */
60*2a33c5a2SEduard Zingerman 	BPF_EXIT_INSN(),
61*2a33c5a2SEduard Zingerman 	},
62*2a33c5a2SEduard Zingerman 	.result = ACCEPT,
63*2a33c5a2SEduard Zingerman 	/* Use prog type that requires return value in range [0, 1] */
64*2a33c5a2SEduard Zingerman 	.prog_type = BPF_PROG_TYPE_SK_LOOKUP,
65*2a33c5a2SEduard Zingerman 	.expected_attach_type = BPF_SK_LOOKUP,
66*2a33c5a2SEduard Zingerman 	.runs = -1,
67*2a33c5a2SEduard Zingerman },
68