[PATCH bpf-next 2/2] selftests/bpf: additional stack depth tests
flat view
STALE3221d
From: Alexei Starovoitov <ast@kernel.org>
Date: 2017-12-22 21:33:31
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Shuah Khan, Linus Torvalds
to test inner logic of stack depth tracking Signed-off-by: Alexei Starovoitov <ast@kernel.org> --- tools/testing/selftests/bpf/test_verifier.c | 50 +++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 71fb0be81b78..e0b21c95c3bc 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c@@ -8764,6 +8764,56 @@ static struct bpf_test tests[] = { .result = REJECT, }, { + "calls: stack depth check using three frames. test1", + .insns = { + /* main */ + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 4), /* call A */ + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 5), /* call B */ + BPF_ST_MEM(BPF_B, BPF_REG_10, -32, 0), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + /* A */ + BPF_ST_MEM(BPF_B, BPF_REG_10, -256, 0), + BPF_EXIT_INSN(), + /* B */ + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, -3), /* call A */ + BPF_ST_MEM(BPF_B, BPF_REG_10, -64, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_XDP, + /* though stack_main=32, stack_A=256, stack_B=64 + * and max(main+A, main+A+B) < 512 the program is rejected + * since stack tracking is conservative + * frame[0]=32, frame[1]=256, frame[2]=256 + */ + .errstr = "combined stack size", + .result = REJECT, + }, + { + "calls: stack depth check using three frames. test2", + .insns = { + /* main */ + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 4), /* call A */ + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 5), /* call B */ + BPF_ST_MEM(BPF_B, BPF_REG_10, -32, 0), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + /* A */ + BPF_ST_MEM(BPF_B, BPF_REG_10, -64, 0), + BPF_EXIT_INSN(), + /* B */ + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, -3), /* call A */ + BPF_ST_MEM(BPF_B, BPF_REG_10, -256, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_XDP, + /* though stack_main=32, stack_A=64, stack_B=256 + * and max(main+A, main+A+B) < 512 the program is accepted + * since frame[0]=32, frame[1]=256, frame[2]=64 + */ + .result = ACCEPT, + }, + { "calls: spill into caller stack frame", .insns = { BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
--
2.9.5