Messages in this thread Patch in this message |  | | From | Hao Sun <> | Subject | [PATCH bpf-next 2/2] selftests/bpf: check null propagation only neither reg is PTR_TO_BTF_ID | Date | Mon, 12 Dec 2022 12:15:47 +0800 |
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Verify that nullness information is not porpagated in the branches of register to register JEQ and JNE operations if one of them is PTR_TO_BTF_ID.
Signed-off-by: Hao Sun <sunhao.th@gmail.com> --- .../bpf/verifier/jeq_infer_not_null.c | 22 +++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/tools/testing/selftests/bpf/verifier/jeq_infer_not_null.c b/tools/testing/selftests/bpf/verifier/jeq_infer_not_null.c index 67a1c07ead34..b2b215227d97 100644 --- a/tools/testing/selftests/bpf/verifier/jeq_infer_not_null.c +++ b/tools/testing/selftests/bpf/verifier/jeq_infer_not_null.c @@ -172,3 +172,25 @@ .prog_type = BPF_PROG_TYPE_XDP, .result = ACCEPT, }, +{ + "jne/jeq infer not null, PTR_TO_MAP_OR_NULL unchanged with PTR_TO_BTF_ID reg", + .insns = { + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), + BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0), + BPF_LD_MAP_FD(BPF_REG_1, 0), + /* r6 = bpf_map->inner_map_meta; */ + BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 8), + /* r0 = map_lookup_elem(r1, r2); */ + BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), + /* if (r0 == r6) read *r0; */ + BPF_JMP_REG(BPF_JEQ, BPF_REG_6, BPF_REG_0, 1), + BPF_EXIT_INSN(), + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .fixup_map_hash_8b = { 3 }, + .prog_type = BPF_PROG_TYPE_XDP, + .result = REJECT, + .errstr = "R0 invalid mem access 'map_value_or_null'", +}, -- 2.38.1
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