Some new verifier tests that hit some important gaps in the parameter
space for atomic ops.
There are already exhaustive tests for the JIT part in
lib/test_bpf.c, but these exercise the verifier too.
Signed-off-by: Brendan Jackman <jackmanb@xxxxxxxxxx>
---
.../selftests/bpf/verifier/atomic_cmpxchg.c | 38 +++++++++++++
.../selftests/bpf/verifier/atomic_fetch.c | 57 +++++++++++++++++++
.../selftests/bpf/verifier/atomic_invalid.c | 25 ++++++++
3 files changed, 120 insertions(+)
create mode 100644 tools/testing/selftests/bpf/verifier/atomic_fetch.c
create mode 100644 tools/testing/selftests/bpf/verifier/atomic_invalid.c
diff --git a/tools/testing/selftests/bpf/verifier/atomic_cmpxchg.c b/tools/testing/selftests/bpf/verifier/atomic_cmpxchg.c
index 6e52dfc64415..c22dc83a41fd 100644
--- a/tools/testing/selftests/bpf/verifier/atomic_cmpxchg.c
+++ b/tools/testing/selftests/bpf/verifier/atomic_cmpxchg.c
@@ -119,3 +119,41 @@
},
.result = ACCEPT,
},
+{
+ "Dest pointer in r0 - fail",
+ .insns = {
+ /* val = 0; */
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+ /* r0 = &val */
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
+ /* r0 = atomic_cmpxchg(&val, r0, 1); */
+ BPF_MOV64_IMM(BPF_REG_1, 1),
+ BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
+ /* if (r0 != 0) exit(1); */
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ /* exit(0); */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+},
+{
+ "Dest pointer in r0 - succeed",
+ .insns = {
+ /* r0 = &val */
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
+ /* val = r0; */
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
+ /* r0 = atomic_cmpxchg(&val, r0, 0); */
+ BPF_MOV64_IMM(BPF_REG_1, 0),
+ BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
+ /* r1 = *r0 */
+ BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
+ /* exit(0); */
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+},
diff --git a/tools/testing/selftests/bpf/verifier/atomic_fetch.c b/tools/testing/selftests/bpf/verifier/atomic_fetch.c
new file mode 100644
index 000000000000..3bc9ff7a860b
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/atomic_fetch.c
@@ -0,0 +1,57 @@
+#define __ATOMIC_FETCH_OP_TEST(src_reg, dst_reg, operand1, op, operand2, expect) \
+ { \
+ "atomic fetch " #op ", src=" #dst_reg " dst=" #dst_reg, \
+ .insns = { \
+ /* u64 val = operan1; */ \
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, operand1), \
+ /* u64 old = atomic_fetch_add(&val, operand2); */ \
+ BPF_MOV64_REG(dst_reg, BPF_REG_10), \
+ BPF_MOV64_IMM(src_reg, operand2), \
+ BPF_ATOMIC_OP(BPF_DW, op, \
+ dst_reg, src_reg, -8), \
+ /* if (old != operand1) exit(1); */ \
+ BPF_JMP_IMM(BPF_JEQ, src_reg, operand1, 2), \
+ BPF_MOV64_IMM(BPF_REG_0, 1), \
+ BPF_EXIT_INSN(), \
+ /* if (val != result) exit (2); */ \
+ BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -8), \
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, expect, 2), \
+ BPF_MOV64_IMM(BPF_REG_0, 2), \
+ BPF_EXIT_INSN(), \
+ /* exit(0); */ \
+ BPF_MOV64_IMM(BPF_REG_0, 0), \
+ BPF_EXIT_INSN(), \
+ }, \
+ .result = ACCEPT, \
+ }
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 1, BPF_ADD | BPF_FETCH, 2, 3),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 0x010, BPF_AND | BPF_FETCH, 0x011, 0x010),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 0x010, BPF_OR | BPF_FETCH, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 0x010, BPF_XOR | BPF_FETCH, 0x011, 0x001),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_2, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_0, BPF_REG_1, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_1, BPF_REG_0, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_2, BPF_REG_3, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_4, BPF_REG_5, 0x010, BPF_XCHG, 0x011, 0x011),
+__ATOMIC_FETCH_OP_TEST(BPF_REG_9, BPF_REG_8, 0x010, BPF_XCHG, 0x011, 0x011),
+#undef __ATOMIC_FETCH_OP_TEST
diff --git a/tools/testing/selftests/bpf/verifier/atomic_invalid.c b/tools/testing/selftests/bpf/verifier/atomic_invalid.c
new file mode 100644
index 000000000000..39272720b2f6
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/atomic_invalid.c
@@ -0,0 +1,25 @@
+#define __INVALID_ATOMIC_ACCESS_TEST(op) \
+ { \
+ "atomic " #op " access through non-pointer ", \
+ .insns = { \
+ BPF_MOV64_IMM(BPF_REG_0, 1), \
+ BPF_MOV64_IMM(BPF_REG_1, 0), \
+ BPF_ATOMIC_OP(BPF_DW, op, BPF_REG_1, BPF_REG_0, -8), \
+ BPF_MOV64_IMM(BPF_REG_0, 0), \
+ BPF_EXIT_INSN(), \
+ }, \
+ .result = REJECT, \
+ .errstr = "R1 invalid mem access 'inv'" \
+ }
+__INVALID_ATOMIC_ACCESS_TEST(BPF_ADD),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_ADD | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_ADD),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_ADD | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_AND),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_AND | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_OR),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_OR | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_XOR),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_XOR | BPF_FETCH),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_XCHG),
+__INVALID_ATOMIC_ACCESS_TEST(BPF_CMPXCHG),
--
2.33.0.1079.g6e70778dc9-goog
