From: Alexei Starovoitov <ast@kernel.org>
Date: Mon, 25 Dec 2017 13:15:41 -0800
Subject: selftests/bpf: additional stack depth tests
Patch-mainline: v4.16-rc1
Git-commit: 6b86c4217c231cbd268bd8c6fda025b27047d3ed
References: bsc#1109837
to test inner logic of stack depth tracking
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
tools/testing/selftests/bpf/test_verifier.c | 121 ++++++++++++++++++++++++++++
1 file changed, 121 insertions(+)
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -9493,6 +9493,127 @@ 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),