This patch adds various verifier test cases:
1) A test case for the pruning issue when tracking alignment
is used.
2) Various PTR_TO_MAP_VALUE_OR_NULL tests to make sure pointer
arithmetic turns such register into UNKNOWN_VALUE type.
3) Test cases for the special treatment of LD_ABS/LD_IND to
make sure verifier doesn't break calling convention here.
Latter is needed, since f.e. arm64 JIT uses r1 - r5 for
storing temporary data, so they really must be marked as
NOT_INIT.
Signed-off-by: Daniel Borkmann <dan...@iogearbox.net>
Acked-by: Alexei Starovoitov <a...@kernel.org>
---
include/linux/filter.h | 10 ++
tools/include/linux/filter.h | 10 ++
tools/testing/selftests/bpf/test_verifier.c | 239 +++++++++++++++++++++++++++-
3 files changed, 255 insertions(+), 4 deletions(-)
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 56197f8..62d948f 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -272,6 +272,16 @@
.off = OFF, \
.imm = IMM })
+/* Unconditional jumps, goto pc + off16 */
+
+#define BPF_JMP_A(OFF) \
+ ((struct bpf_insn) { \
+ .code = BPF_JMP | BPF_JA, \
+ .dst_reg = 0, \
+ .src_reg = 0, \
+ .off = OFF, \
+ .imm = 0 })
+
/* Function call */
#define BPF_EMIT_CALL(FUNC) \
diff --git a/tools/include/linux/filter.h b/tools/include/linux/filter.h
index 390d7c9..4ce25d4 100644
--- a/tools/include/linux/filter.h
+++ b/tools/include/linux/filter.h
@@ -208,6 +208,16 @@
.off = OFF, \
.imm = IMM })
+/* Unconditional jumps, goto pc + off16 */
+
+#define BPF_JMP_A(OFF) \
+ ((struct bpf_insn) { \
+ .code = BPF_JMP | BPF_JA, \
+ .dst_reg = 0, \
+ .src_reg = 0, \
+ .off = OFF, \
+ .imm = 0 })
+
/* Function call */
#define BPF_EMIT_CALL(FUNC) \
diff --git a/tools/testing/selftests/bpf/test_verifier.c
b/tools/testing/selftests/bpf/test_verifier.c
index 3773562..cabb19b 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -49,6 +49,7 @@
#define MAX_NR_MAPS 4
#define F_NEEDS_EFFICIENT_UNALIGNED_ACCESS (1 << 0)
+#define F_LOAD_WITH_STRICT_ALIGNMENT (1 << 1)
struct bpf_test {
const char *descr;
@@ -2615,6 +2616,30 @@ struct test_val {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
+ "direct packet access: test17 (pruning, alignment)",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct __sk_buff, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ offsetof(struct __sk_buff, data_end)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_1,
+ offsetof(struct __sk_buff, mark)),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 14),
+ BPF_JMP_IMM(BPF_JGT, BPF_REG_7, 1, 4),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 1),
+ BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, -4),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
+ BPF_JMP_A(-6),
+ },
+ .errstr = "misaligned packet access off 2+15+-4 size 4",
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
+ },
+ {
"helper access to packet: test1, valid packet_ptr range",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
@@ -3341,6 +3366,70 @@ struct test_val {
.prog_type = BPF_PROG_TYPE_SCHED_CLS
},
{
+ "alu ops on ptr_to_map_value_or_null, 1",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_1, 10),
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
+ 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_MOV64_REG(BPF_REG_4, BPF_REG_0),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 2),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+ BPF_ST_MEM(BPF_DW, BPF_REG_4, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map1 = { 4 },
+ .errstr = "R4 invalid mem access",
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS
+ },
+ {
+ "alu ops on ptr_to_map_value_or_null, 2",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_1, 10),
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
+ 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_MOV64_REG(BPF_REG_4, BPF_REG_0),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_4, -1),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+ BPF_ST_MEM(BPF_DW, BPF_REG_4, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map1 = { 4 },
+ .errstr = "R4 invalid mem access",
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS
+ },
+ {
+ "alu ops on ptr_to_map_value_or_null, 3",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_1, 10),
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
+ 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_MOV64_REG(BPF_REG_4, BPF_REG_0),
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_4, 1),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
+ BPF_ST_MEM(BPF_DW, BPF_REG_4, 0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map1 = { 4 },
+ .errstr = "R4 invalid mem access",
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS
+ },
+ {
"invalid memory access with multiple map_lookup_elem calls",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 10),
@@ -4937,7 +5026,149 @@ struct test_val {
.fixup_map_in_map = { 3 },
.errstr = "R1 type=map_value_or_null expected=map_ptr",
.result = REJECT,
- }
+ },
+ {
+ "ld_abs: check calling conv, r1",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_1, 0),
+ BPF_LD_ABS(BPF_W, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R1 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_abs: check calling conv, r2",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_LD_ABS(BPF_W, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R2 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_abs: check calling conv, r3",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_3, 0),
+ BPF_LD_ABS(BPF_W, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_3),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R3 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_abs: check calling conv, r4",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_4, 0),
+ BPF_LD_ABS(BPF_W, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_4),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R4 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_abs: check calling conv, r5",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_5, 0),
+ BPF_LD_ABS(BPF_W, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_5),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R5 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_abs: check calling conv, r7",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_7, 0),
+ BPF_LD_ABS(BPF_W, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_7),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
+ {
+ "ld_ind: check calling conv, r1",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_1, 1),
+ BPF_LD_IND(BPF_W, BPF_REG_1, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R1 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_ind: check calling conv, r2",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_2, 1),
+ BPF_LD_IND(BPF_W, BPF_REG_2, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R2 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_ind: check calling conv, r3",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_3, 1),
+ BPF_LD_IND(BPF_W, BPF_REG_3, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_3),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R3 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_ind: check calling conv, r4",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_4, 1),
+ BPF_LD_IND(BPF_W, BPF_REG_4, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_4),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R4 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_ind: check calling conv, r5",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_5, 1),
+ BPF_LD_IND(BPF_W, BPF_REG_5, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_5),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "R5 !read_ok",
+ .result = REJECT,
+ },
+ {
+ "ld_ind: check calling conv, r7",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ BPF_MOV64_IMM(BPF_REG_7, 1),
+ BPF_LD_IND(BPF_W, BPF_REG_7, -0x200000),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_7),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
};
static int probe_filter_length(const struct bpf_insn *fp)
@@ -5059,9 +5290,9 @@ static void do_test_single(struct bpf_test *test, bool
unpriv,
do_test_fixup(test, prog, map_fds);
- fd_prog = bpf_load_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER,
- prog, prog_len, "GPL", 0, bpf_vlog,
- sizeof(bpf_vlog));
+ fd_prog = bpf_verify_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER,
+ prog, prog_len, test->flags &
F_LOAD_WITH_STRICT_ALIGNMENT,
+ "GPL", 0, bpf_vlog, sizeof(bpf_vlog));
expected_ret = unpriv && test->result_unpriv != UNDEF ?
test->result_unpriv : test->result;
--
1.9.3
