Commit 7960d02d authored by Brendan Jackman's avatar Brendan Jackman Committed by Alexei Starovoitov
Browse files

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: default avatarBrendan Jackman <jackmanb@google.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211015093318.1273686-1-jackmanb@google.com
parent 99aaebfc

tools/testing/selftests/bpf/verifier/atomic_cmpxchg.c

+38 −0
Original line number Diff line number Diff line
@@ -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,

},

tools/testing/selftests/bpf/verifier/atomic_fetch.c

0 → 100644
+57 −0
Original line number Diff line number Diff line 
#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

tools/testing/selftests/bpf/verifier/atomic_invalid.c

0 → 100644
+25 −0
Original line number Diff line number Diff line 
#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),