{
"BPF_ST_MEM stack imm non-zero",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 42),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, -42),
/* if value is tracked correctly R0 is zero */
BPF_EXIT_INSN(),
},
.result = ACCEPT,
/* Use prog type that requires return value in range [0, 1] */
.prog_type = BPF_PROG_TYPE_SK_LOOKUP,
.expected_attach_type = BPF_SK_LOOKUP,
.runs = -1,
},
{
"BPF_ST_MEM stack imm zero",
.insns = {
/* mark stack 0000 0000 */
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
/* read and sum a few bytes */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -8),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -4),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_10, -1),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
/* if value is tracked correctly R0 is zero */
BPF_EXIT_INSN(),
},
.result = ACCEPT,
/* Use prog type that requires return value in range [0, 1] */
.prog_type = BPF_PROG_TYPE_SK_LOOKUP,
.expected_attach_type = BPF_SK_LOOKUP,
.runs = -1,
},
{
"BPF_ST_MEM stack imm zero, variable offset",
.insns = {
/* set fp[-16], fp[-24] to zeros */
BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_10, -24, 0),
/* r0 = random value in range [-32, -15] */
BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
BPF_JMP_IMM(BPF_JLE, BPF_REG_0, 16, 2),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 32),
/* fp[r0] = 0, make a variable offset write of zero,
* this should preserve zero marks on stack.
*/
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_10),
BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
/* r0 = fp[-20], if variable offset write was tracked correctly
* r0 would be a known zero.
*/
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_10, -20),
/* Would fail return code verification if r0 range is not tracked correctly. */
BPF_EXIT_INSN(),
},
.result = ACCEPT,
/* Use prog type that requires return value in range [0, 1] */
.prog_type = BPF_PROG_TYPE_SK_LOOKUP,
.expected_attach_type = BPF_SK_LOOKUP,
.runs = -1,
},
{
"BPF_ST_MEM stack imm sign",
/* Check if verifier correctly reasons about sign of an
* immediate spilled to stack by BPF_ST instruction.
*
* fp[-8] = -44;
* r0 = fp[-8];
* if r0 s< 0 goto ret0;
* r0 = -1;
* exit;
* ret0:
* r0 = 0;
* exit;
*/
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, -44),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_JMP_IMM(BPF_JSLT, BPF_REG_0, 0, 2),
BPF_MOV64_IMM(BPF_REG_0, -1),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
/* Use prog type that requires return value in range [0, 1] */
.prog_type = BPF_PROG_TYPE_SK_LOOKUP,
.expected_attach_type = BPF_SK_LOOKUP,
.result = VERBOSE_ACCEPT,
.runs = -1,
.errstr = "0: (7a) *(u64 *)(r10 -8) = -44 ; R10=fp0 fp-8_w=-44\
2: (c5) if r0 s< 0x0 goto pc+2\
R0_w=-44",
},
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