bpf: add various test cases for alu op on mixed dst register types

Add couple of test_verifier tests to check sanitation of alu op insn
with pointer and scalar type coming from different paths. This also
includes BPF insns of the test reproducer provided by Jann Horn.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Daniel Borkmann 2019-01-06 00:54:38 +01:00 committed by Alexei Starovoitov
parent d3bd7413e0
commit 1cbbcfbbd5

View File

@ -6933,6 +6933,126 @@ static struct bpf_test tests[] = {
.result = ACCEPT,
.retval = 1,
},
{
"map access: mixing value pointer and scalar, 1",
.insns = {
// load map value pointer into r0 and r2
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_LD_MAP_FD(BPF_REG_ARG1, 0),
BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_FP),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG2, -16),
BPF_ST_MEM(BPF_DW, BPF_REG_FP, -16, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
// load some number from the map into r1
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
// depending on r1, branch:
BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 3),
// branch A
BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_JMP_A(2),
// branch B
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_MOV64_IMM(BPF_REG_3, 0x100000),
// common instruction
BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
// depending on r1, branch:
BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 1),
// branch A
BPF_JMP_A(4),
// branch B
BPF_MOV64_IMM(BPF_REG_0, 0x13371337),
// verifier follows fall-through
BPF_JMP_IMM(BPF_JNE, BPF_REG_2, 0x100000, 2),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
// fake-dead code; targeted from branch A to
// prevent dead code sanitization
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_array_48b = { 1 },
.result = ACCEPT,
.result_unpriv = REJECT,
.errstr_unpriv = "R2 tried to add from different pointers or scalars",
.retval = 0,
},
{
"map access: mixing value pointer and scalar, 2",
.insns = {
// load map value pointer into r0 and r2
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_LD_MAP_FD(BPF_REG_ARG1, 0),
BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_FP),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG2, -16),
BPF_ST_MEM(BPF_DW, BPF_REG_FP, -16, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
// load some number from the map into r1
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
// depending on r1, branch:
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 3),
// branch A
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_MOV64_IMM(BPF_REG_3, 0x100000),
BPF_JMP_A(2),
// branch B
BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
BPF_MOV64_IMM(BPF_REG_3, 0),
// common instruction
BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
// depending on r1, branch:
BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 1),
// branch A
BPF_JMP_A(4),
// branch B
BPF_MOV64_IMM(BPF_REG_0, 0x13371337),
// verifier follows fall-through
BPF_JMP_IMM(BPF_JNE, BPF_REG_2, 0x100000, 2),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
// fake-dead code; targeted from branch A to
// prevent dead code sanitization
BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_array_48b = { 1 },
.result = ACCEPT,
.result_unpriv = REJECT,
.errstr_unpriv = "R2 tried to add from different maps or paths",
.retval = 0,
},
{
"sanitation: alu with different scalars",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_LD_MAP_FD(BPF_REG_ARG1, 0),
BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_FP),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG2, -16),
BPF_ST_MEM(BPF_DW, BPF_REG_FP, -16, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
BPF_EXIT_INSN(),
BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 3),
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_MOV64_IMM(BPF_REG_3, 0x100000),
BPF_JMP_A(2),
BPF_MOV64_IMM(BPF_REG_2, 42),
BPF_MOV64_IMM(BPF_REG_3, 0x100001),
BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
BPF_EXIT_INSN(),
},
.fixup_map_array_48b = { 1 },
.result = ACCEPT,
.retval = 0x100000,
},
{
"map access: value_ptr += known scalar, upper oob arith, test 1",
.insns = {