Commit 4ca13d10 authored by Xu Kuohai's avatar Xu Kuohai Committed by Alexei Starovoitov
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selftests/bpf: Rewrite two infinite loops in bound check cases 



The two infinite loops in bound check cases added by commit
1a3148fc ("selftests/bpf: Check when bounds are not in the 32-bit range")
increased the execution time of test_verifier from about 6 seconds to
about 9 seconds. Rewrite these two infinite loops to finite loops to get
rid of this extra time cost.

Signed-off-by: default avatarXu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20230329011048.1721937-1-xukuohai@huaweicloud.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 8a9abe02

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

+16 −8
Original line number Diff line number Diff line
@@ -784,22 +784,26 @@ 
	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_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 13),



	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_2, 0x8000000000000fff),

	BPF_LD_IMM64(BPF_REG_0, 0x8000000000000000),

	BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),

	BPF_JMP_REG(BPF_JSGT, BPF_REG_0, BPF_REG_2, 3),

	/* r1 signed range is [S64_MIN, S64_MAX] */

	BPF_JMP_REG(BPF_JSLT, BPF_REG_0, BPF_REG_1, -2),

	BPF_JMP_REG(BPF_JSLT, BPF_REG_0, BPF_REG_1, -3),



	BPF_MOV64_IMM(BPF_REG_0, 1),

	BPF_EXIT_INSN(),



	BPF_MOV64_IMM(BPF_REG_0, 0),

	BPF_EXIT_INSN(),

	},

	.errstr = "BPF program is too large",

	.result = REJECT,

	.result = ACCEPT,

	.prog_type = BPF_PROG_TYPE_XDP,

},

{
@@ -856,21 +860,25 @@ 
	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_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 10),



	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_2, 0x80000fff),

	BPF_MOV32_IMM(BPF_REG_0, 0x80000000),

	BPF_ALU32_IMM(BPF_ADD, BPF_REG_0, 1),

	BPF_JMP32_REG(BPF_JSGT, BPF_REG_0, BPF_REG_2, 3),

	/* r1 signed range is [S32_MIN, S32_MAX] */

	BPF_JMP32_REG(BPF_JSLT, BPF_REG_0, BPF_REG_1, -2),

	BPF_JMP32_REG(BPF_JSLT, BPF_REG_0, BPF_REG_1, -3),



	BPF_MOV64_IMM(BPF_REG_0, 1),

	BPF_EXIT_INSN(),



	BPF_MOV64_IMM(BPF_REG_0, 0),

	BPF_EXIT_INSN(),

	},

	.errstr = "BPF program is too large",

	.result = REJECT,

	.result = ACCEPT,

	.prog_type = BPF_PROG_TYPE_XDP,

},