From 7960d02dddccc0676d4a1b58e9964718b47388e1 Mon Sep 17 00:00:00 2001 From: Brendan Jackman Date: Fri, 15 Oct 2021 09:33:18 +0000 Subject: selftests/bpf: Some more atomic tests 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 Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211015093318.1273686-1-jackmanb@google.com --- .../selftests/bpf/verifier/atomic_cmpxchg.c | 38 +++++++++++++++ .../testing/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 (limited to 'tools/testing/selftests/bpf/verifier') 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), -- cgit v1.2.3-59-g8ed1b