From:   Xu Kuohai <xukuohai@huaweicloud.com>
To:     bpf@vger.kernel.org, linux-kselftest@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        John Fastabend <john.fastabend@gmail.com>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Mykola Lysenko <mykolal@fb.com>, Shuah Khan <shuah@kernel.org>
Subject: [PATCH bpf-next 2/2] selftests/bpf: check bounds not in the 32-bit range
Date:   Tue,  7 Mar 2023 17:04:49 -0500
Message-Id: <20230307220449.2933650-3-xukuohai@huaweicloud.com>
In-Reply-To: <20230307220449.2933650-1-xukuohai@huaweicloud.com>
References: <20230307220449.2933650-1-xukuohai@huaweicloud.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Add cases to check if bound is updated correctly when 64-bit value is
not in the 32-bit range.

Signed-off-by: Xu Kuohai <xukuohai@huaweicloud.com>
---
 tools/testing/selftests/bpf/verifier/bounds.c | 121 ++++++++++++++++++
 1 file changed, 121 insertions(+)

diff --git a/tools/testing/selftests/bpf/verifier/bounds.c b/tools/testing/selftests/bpf/verifier/bounds.c
index 33125d5f6772..74b1917d4208 100644
--- a/tools/testing/selftests/bpf/verifier/bounds.c
+++ b/tools/testing/selftests/bpf/verifier/bounds.c
@@ -753,3 +753,124 @@
 	.result_unpriv = REJECT,
 	.result = ACCEPT,
 },
+{
+	"bound check with JMP_JLT for crossing 64-bit signed boundary",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 8),
+
+	BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+	BPF_LD_IMM64(BPF_REG_0, 0x7fffffffffffff10),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+	BPF_LD_IMM64(BPF_REG_0, 0x8000000000000000),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
+	/* r1 unsigned range is [0x7fffffffffffff10, 0x800000000000000f] */
+	BPF_JMP_REG(BPF_JLT, BPF_REG_0, BPF_REG_1, -2),
+
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+},
+{
+	"bound check with JMP_JSLT for crossing 64-bit signed boundary",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 8),
+
+	BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+	BPF_LD_IMM64(BPF_REG_0, 0x7fffffffffffff10),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+	BPF_LD_IMM64(BPF_REG_0, 0x8000000000000000),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
+	/* r1 signed range is [S64_MIN, S64_MAX] */
+	BPF_JMP_REG(BPF_JSLT, BPF_REG_0, BPF_REG_1, -2),
+
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "BPF program is too large",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+},
+{
+	"bound check for loop upper bound greater than U32_MAX",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 8),
+
+	BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+	BPF_LD_IMM64(BPF_REG_0, 0x100000000),
+	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+	BPF_LD_IMM64(BPF_REG_0, 0x100000000),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
+	BPF_JMP_REG(BPF_JLT, BPF_REG_0, BPF_REG_1, -2),
+
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+},
+{
+	"bound check with JMP32_JLT for crossing 32-bit signed boundary",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 6),
+
+	BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+	BPF_MOV32_IMM(BPF_REG_0, 0x7fffff10),
+	BPF_ALU32_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+	BPF_MOV32_IMM(BPF_REG_0, 0x80000000),
+	BPF_ALU32_IMM(BPF_ADD, BPF_REG_0, 1),
+	/* r1 unsigned range is [0, 0x8000000f] */
+	BPF_JMP32_REG(BPF_JLT, BPF_REG_0, BPF_REG_1, -2),
+
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.result = ACCEPT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+},
+{
+	"bound check with JMP32_JSLT for crossing 32-bit signed boundary",
+	.insns = {
+	BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, offsetof(struct xdp_md, data)),
+	BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, offsetof(struct xdp_md, data_end)),
+	BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+	BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1),
+	BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 6),
+
+	BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_2, 0),
+	BPF_MOV32_IMM(BPF_REG_0, 0x7fffff10),
+	BPF_ALU32_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+
+	BPF_MOV32_IMM(BPF_REG_0, 0x80000000),
+	BPF_ALU32_IMM(BPF_ADD, BPF_REG_0, 1),
+	/* r1 signed range is [S32_MIN, S32_MAX] */
+	BPF_JMP32_REG(BPF_JSLT, BPF_REG_0, BPF_REG_1, -2),
+
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.errstr = "BPF program is too large",
+	.result = REJECT,
+	.prog_type = BPF_PROG_TYPE_XDP,
+},
-- 
2.30.2