diff options
Diffstat (limited to 'tools/testing/selftests/bpf')
| -rw-r--r-- | tools/testing/selftests/bpf/verifier/bpf_st_mem.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/verifier/bpf_st_mem.c b/tools/testing/selftests/bpf/verifier/bpf_st_mem.c index 932903f9e585..3af2501082b2 100644 --- a/tools/testing/selftests/bpf/verifier/bpf_st_mem.c +++ b/tools/testing/selftests/bpf/verifier/bpf_st_mem.c @@ -35,3 +35,33 @@ .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, +}, |