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selftests/bpf: additional stack depth tests
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to test inner logic of stack depth tracking

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Alexei Starovoitov authored and Daniel Borkmann committed Dec 27, 2017
1 parent 70a87ff commit 6b86c42
Showing 1 changed file with 121 additions and 0 deletions.
121 changes: 121 additions & 0 deletions tools/testing/selftests/bpf/test_verifier.c
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Original file line number Diff line number Diff line change
Expand Up @@ -8763,6 +8763,127 @@ static struct bpf_test tests[] = {
.errstr = "combined stack size",
.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 = {
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