From 6b86c4217c231cbd268bd8c6fda025b27047d3ed Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Mon, 25 Dec 2017 13:15:41 -0800 Subject: [PATCH] selftests/bpf: additional stack depth tests to test inner logic of stack depth tracking Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann --- tools/testing/selftests/bpf/test_verifier.c | 121 ++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index 41dcc7dbba42..b5a7a6c530dc 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -8764,6 +8764,127 @@ 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, + /* stack_main=32, stack_A=256, stack_B=64 + * and max(main+A, main+A+B) < 512 + */ + .result = ACCEPT, + }, + { + "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, + /* stack_main=32, stack_A=64, stack_B=256 + * and max(main+A, main+A+B) < 512 + */ + .result = ACCEPT, + }, + { + "calls: stack depth check using three frames. test3", + .insns = { + /* main */ + BPF_MOV64_REG(BPF_REG_6, BPF_REG_1), + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 6), /* call A */ + BPF_MOV64_REG(BPF_REG_1, BPF_REG_6), + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 8), /* call B */ + BPF_JMP_IMM(BPF_JGE, BPF_REG_6, 0, 1), + BPF_ST_MEM(BPF_B, BPF_REG_10, -64, 0), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + /* A */ + BPF_JMP_IMM(BPF_JLT, BPF_REG_1, 10, 1), + BPF_EXIT_INSN(), + BPF_ST_MEM(BPF_B, BPF_REG_10, -224, 0), + BPF_JMP_IMM(BPF_JA, 0, 0, -3), + /* B */ + BPF_JMP_IMM(BPF_JGT, BPF_REG_1, 2, 1), + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, -6), /* call A */ + BPF_ST_MEM(BPF_B, BPF_REG_10, -256, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_XDP, + /* stack_main=64, stack_A=224, stack_B=256 + * and max(main+A, main+A+B) > 512 + */ + .errstr = "combined stack", + .result = REJECT, + }, + { + "calls: stack depth check using three frames. test4", + /* void main(void) { + * func1(0); + * func1(1); + * func2(1); + * } + * void func1(int alloc_or_recurse) { + * if (alloc_or_recurse) { + * frame_pointer[-300] = 1; + * } else { + * func2(alloc_or_recurse); + * } + * } + * void func2(int alloc_or_recurse) { + * if (alloc_or_recurse) { + * frame_pointer[-300] = 1; + * } + * } + */ + .insns = { + /* main */ + BPF_MOV64_IMM(BPF_REG_1, 0), + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 6), /* call A */ + BPF_MOV64_IMM(BPF_REG_1, 1), + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 4), /* call A */ + BPF_MOV64_IMM(BPF_REG_1, 1), + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 7), /* call B */ + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + /* A */ + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 2), + BPF_ST_MEM(BPF_B, BPF_REG_10, -300, 0), + BPF_EXIT_INSN(), + BPF_RAW_INSN(BPF_JMP|BPF_CALL, 0, 1, 0, 1), /* call B */ + BPF_EXIT_INSN(), + /* B */ + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1), + BPF_ST_MEM(BPF_B, BPF_REG_10, -300, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_XDP, + .result = REJECT, + .errstr = "combined stack", + }, + { "calls: spill into caller stack frame", .insns = { BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), -- 2.11.0