kernel/tools/testing/selftests/bpf/verifier/search_pruning.c
2024-07-22 17:22:30 +08:00

196 lines
6.3 KiB
C

{
"pointer/scalar confusion in state equality check (way 1)",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
BPF_JMP_A(1),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
BPF_JMP_A(0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.result = ACCEPT,
.retval = POINTER_VALUE,
.result_unpriv = REJECT,
.errstr_unpriv = "R0 leaks addr as return value"
},
{
"pointer/scalar confusion in state equality check (way 2)",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 2),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
BPF_JMP_A(1),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.result = ACCEPT,
.retval = POINTER_VALUE,
.result_unpriv = REJECT,
.errstr_unpriv = "R0 leaks addr as return value"
},
{
"liveness pruning and write screening",
.insns = {
/* Get an unknown value */
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 0),
/* branch conditions teach us nothing about R2 */
BPF_JMP_IMM(BPF_JGE, BPF_REG_2, 0, 1),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGE, BPF_REG_2, 0, 1),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.errstr = "R0 !read_ok",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_LWT_IN,
},
{
"varlen_map_value_access pruning",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8),
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
BPF_MOV32_IMM(BPF_REG_2, MAX_ENTRIES),
BPF_JMP_REG(BPF_JSGT, BPF_REG_2, BPF_REG_1, 1),
BPF_MOV32_IMM(BPF_REG_1, 0),
BPF_ALU32_IMM(BPF_LSH, BPF_REG_1, 2),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_JMP_IMM(BPF_JA, 0, 0, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, offsetof(struct test_val, foo)),
BPF_EXIT_INSN(),
},
.fixup_map_hash_48b = { 3 },
.errstr_unpriv = "R0 leaks addr",
.errstr = "R0 unbounded memory access",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"search pruning: all branches should be verified (nop operation)",
.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),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 11),
BPF_LDX_MEM(BPF_DW, BPF_REG_3, BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_3, 0xbeef, 2),
BPF_MOV64_IMM(BPF_REG_4, 0),
BPF_JMP_A(1),
BPF_MOV64_IMM(BPF_REG_4, 1),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_4, -16),
BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns),
BPF_LDX_MEM(BPF_DW, BPF_REG_5, BPF_REG_10, -16),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_5, 0, 2),
BPF_MOV64_IMM(BPF_REG_6, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_6, 0, 0xdead),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "R6 invalid mem access 'inv'",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
{
"search pruning: all branches should be verified (invalid stack access)",
.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),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8),
BPF_LDX_MEM(BPF_DW, BPF_REG_3, BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_4, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_3, 0xbeef, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_4, -16),
BPF_JMP_A(1),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_4, -24),
BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns),
BPF_LDX_MEM(BPF_DW, BPF_REG_5, BPF_REG_10, -16),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr_unpriv = "invalid read from stack off -16+0 size 8",
.result_unpriv = REJECT,
/* in privileged mode reads from uninitialized stack locations are permitted */
.result = ACCEPT,
},
{
"allocated_stack",
.insns = {
BPF_ALU64_REG(BPF_MOV, BPF_REG_6, BPF_REG_1),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_prandom_u32),
BPF_ALU64_REG(BPF_MOV, BPF_REG_7, BPF_REG_0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_6, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_10, -8),
BPF_STX_MEM(BPF_B, BPF_REG_10, BPF_REG_7, -9),
BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_10, -9),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.result_unpriv = ACCEPT,
.insn_processed = 15,
},
/* The test performs a conditional 64-bit write to a stack location
* fp[-8], this is followed by an unconditional 8-bit write to fp[-8],
* then data is read from fp[-8]. This sequence is unsafe.
*
* The test would be mistakenly marked as safe w/o dst register parent
* preservation in verifier.c:copy_register_state() function.
*
* Note the usage of BPF_F_TEST_STATE_FREQ to force creation of the
* checkpoint state after conditional 64-bit assignment.
*/
{
"write tracking and register parent chain bug",
.insns = {
/* r6 = ktime_get_ns() */
BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns),
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
/* r0 = ktime_get_ns() */
BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns),
/* if r0 > r6 goto +1 */
BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_6, 1),
/* *(u64 *)(r10 - 8) = 0xdeadbeef */
BPF_ST_MEM(BPF_DW, BPF_REG_FP, -8, 0xdeadbeef),
/* r1 = 42 */
BPF_MOV64_IMM(BPF_REG_1, 42),
/* *(u8 *)(r10 - 8) = r1 */
BPF_STX_MEM(BPF_B, BPF_REG_FP, BPF_REG_1, -8),
/* r2 = *(u64 *)(r10 - 8) */
BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_FP, -8),
/* exit(0) */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.flags = BPF_F_TEST_STATE_FREQ,
.errstr_unpriv = "invalid read from stack off -8+1 size 8",
.result_unpriv = REJECT,
/* in privileged mode reads from uninitialized stack locations are permitted */
.result = ACCEPT,
},